/* ==========================================================================
   G TO CG CALCULATOR - COMPLETE INTERACTIVE DESIGN SYSTEM
   High-Fidelity Aesthetics: Deep Space Dark Mode, Glassmorphism, Dynamic Orbs
   Modeled after volumetocylinder.com UI/UX with rich mass & weight visualizers
   ========================================================================== */

:root,
[data-theme="dark"] {
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

    /* Theme Palette - Deep Space Dark (Default) */
    --color-bg-deep: #070714;
    --color-bg-body: #0a0a1a;
    --color-bg-card: rgba(18, 18, 42, 0.72);
    --color-bg-card-hover: rgba(24, 24, 56, 0.85);
    --color-bg-card-border: rgba(108, 99, 255, 0.22);
    --color-bg-card-glow: rgba(108, 99, 255, 0.15);

    --color-bg-input: rgba(255, 255, 255, 0.04);
    --color-bg-input-focus: rgba(255, 255, 255, 0.08);
    --color-border-subtle: rgba(255, 255, 255, 0.1);
    --color-border-focus: #6c63ff;

    --color-text-primary: #f0f0f8;
    --color-text-secondary: rgba(240, 240, 248, 0.72);
    --color-text-tertiary: rgba(240, 240, 248, 0.42);

    --color-accent-1: #6c63ff;      /* Electric Violet */
    --color-accent-2: #00d2ff;      /* Vivid Cyan */
    --color-accent-3: #a78bfa;      /* Lilac Glow */
    --color-result-glow: rgba(0, 210, 255, 0.4);
    --color-success: #10b981;
    --color-warning: #f59e0b;

    /* Transitions & Shadows */
    --trans-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --trans-smooth: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
    --shadow-card: 0 16px 40px -10px rgba(0, 0, 0, 0.6), 0 0 0 1px var(--color-bg-card-border), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    --shadow-glow: 0 0 25px rgba(108, 99, 255, 0.35);
}

[data-theme="light"] {
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

    /* Theme Palette - Balanced Soft Grey Modern Canvas (Eye-comfort & High Contrast) */
    --color-bg-deep: #e2e8f0;
    --color-bg-body: #edf1f7;
    --color-bg-card: #ffffff;
    --color-bg-card-hover: #ffffff;
    --color-bg-card-border: rgba(15, 23, 42, 0.09);
    --color-bg-card-glow: rgba(79, 70, 229, 0.04);

    --color-bg-input: #f8fafc;
    --color-bg-input-focus: #ffffff;
    --color-border-subtle: #cbd5e1;
    --color-border-focus: #4f46e5;

    --color-text-primary: #0f172a;
    --color-text-secondary: #334155;
    --color-text-tertiary: #64748b;

    --color-accent-1: #4f46e5;      /* Deep Indigo */
    --color-accent-2: #0284c7;      /* Vivid Sky Blue */
    --color-accent-3: #7c3aed;      /* Violet */
    --color-result-glow: rgba(2, 132, 199, 0.2);
    --color-success: #059669;
    --color-warning: #d97706;

    /* Transitions & Shadows */
    --trans-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --trans-smooth: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
    --shadow-card: 0 4px 20px -2px rgba(15, 23, 42, 0.07), 0 1px 3px rgba(15, 23, 42, 0.04);
    --shadow-glow: 0 0 25px rgba(79, 70, 229, 0.08);
}

/* Base Reset */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    max-width: 100vw;
    width: 100%;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-bg-body);
    color: var(--color-text-primary);
    min-height: 100vh;
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
    max-width: 100vw;
    width: 100%;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 9px;
}
::-webkit-scrollbar-track {
    background: var(--color-bg-deep);
}
::-webkit-scrollbar-thumb {
    background: rgba(108, 99, 255, 0.35);
    border-radius: 6px;
    border: 2px solid var(--color-bg-deep);
}
::-webkit-scrollbar-thumb:hover {
    background: rgba(108, 99, 255, 0.7);
}

::selection {
    background: rgba(108, 99, 255, 0.5);
    color: #ffffff;
}

/* Floating Ambient Glowing Orbs */
.bg-orbs {
    position: fixed;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
    z-index: 0;
}

.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(110px);
    opacity: 0.4;
    animation: orbMorph 22s ease-in-out infinite alternate;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--color-accent-1) 0%, transparent 70%);
    top: -150px;
    left: -120px;
}

.orb-2 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, var(--color-accent-2) 0%, transparent 70%);
    bottom: 5%;
    right: -100px;
    animation-delay: -7s;
}

.orb-3 {
    width: 450px;
    height: 450px;
    background: radial-gradient(circle, var(--color-accent-3) 0%, transparent 70%);
    top: 45%;
    left: 45%;
    opacity: 0.25;
    animation-delay: -14s;
}

.grid-overlay {
    position: absolute;
    inset: 0;
    background-image: 
        linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    opacity: 0.7;
}

@keyframes orbMorph {
    0% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(60px, -50px) scale(1.1); }
    66% { transform: translate(-40px, 60px) scale(0.92); }
    100% { transform: translate(50px, 30px) scale(1.05); }
}

/* Layout Container */
.site-container {
    max-width: 1220px;
    margin: 0 auto;
    padding: 0 24px;
    position: relative;
    z-index: 1;
}

@media (min-width: 768px) {
    .site-container { padding: 0 36px; }
}

/* Glassmorphism Card System */
.glass-card {
    background: var(--color-bg-card);
    backdrop-filter: blur(24px) saturate(1.4);
    -webkit-backdrop-filter: blur(24px) saturate(1.4);
    border: 1px solid var(--color-bg-card-border);
    border-radius: 24px;
    padding: 28px;
    box-shadow: var(--shadow-card);
    transition: transform var(--trans-smooth), border-color var(--trans-smooth), box-shadow var(--trans-smooth);
}

.glass-card:hover {
    border-color: rgba(108, 99, 255, 0.4);
}

/* Typography Helpers */
.gradient-text {
    background: linear-gradient(135deg, #6c63ff 0%, #00d2ff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

.text-accent { color: var(--color-accent-2); }
.text-glow {
    color: var(--color-accent-2);
    text-shadow: 0 0 10px rgba(0, 210, 255, 0.4);
}

/* SITE HEADER */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(10, 10, 26, 0.82);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.header-inner {
    max-width: 1220px;
    margin: 0 auto;
    height: 72px;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--color-text-primary);
}

.brand-icon {
    width: 36px;
    height: 36px;
    transition: transform var(--trans-fast);
}

.header-brand:hover .brand-icon {
    transform: rotate(5deg) scale(1.05);
}

.brand-text {
    font-size: 19px;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.brand-accent {
    color: var(--color-accent-2);
}

.header-nav {
    display: none;
    align-items: center;
    gap: 18px;
}

@media (min-width: 992px) {
    .header-nav { display: flex; }
}

.nav-link {
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: 13.5px;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: 8px;
    transition: color var(--trans-fast), background var(--trans-fast);
}

.nav-link:hover, .nav-link.active {
    color: #ffffff;
    background: rgba(255, 255, 255, 0.06);
}

/* DESKTOP NAV DROPDOWN */
.nav-dropdown-item {
    position: relative;
    display: inline-flex;
    align-items: center;
}

.nav-dropdown-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: transparent;
    border: none;
    cursor: pointer;
    font-family: inherit;
    color: var(--color-text-secondary);
    font-size: 13.5px;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: 8px;
    transition: color var(--trans-fast, 0.2s), background var(--trans-fast, 0.2s);
}

.nav-dropdown-btn:hover,
.nav-dropdown-item:hover .nav-dropdown-btn,
.nav-dropdown-item:focus-within .nav-dropdown-btn {
    color: #ffffff;
    background: rgba(255, 255, 255, 0.06);
}

.nav-dropdown-btn .dropdown-arrow {
    transition: transform 0.2s ease;
    opacity: 0.75;
}

.nav-dropdown-item:hover .nav-dropdown-btn .dropdown-arrow,
.nav-dropdown-item:focus-within .nav-dropdown-btn .dropdown-arrow {
    transform: rotate(180deg);
    opacity: 1;
}

/* Floating Mega Dropdown Menu */
.nav-dropdown-menu {
    position: absolute;
    top: calc(100% + 6px);
    left: 50%;
    transform: translateX(-50%) translateY(8px);
    width: 680px;
    max-width: 95vw;
    background: rgba(14, 14, 34, 0.98);
    backdrop-filter: blur(28px);
    -webkit-backdrop-filter: blur(28px);
    border: 1px solid rgba(108, 99, 255, 0.3);
    border-radius: 16px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.7), 0 0 30px rgba(108, 99, 255, 0.15);
    padding: 16px;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
    z-index: 1000;
}

.nav-dropdown-item:hover .nav-dropdown-menu,
.nav-dropdown-item:focus-within .nav-dropdown-menu,
.nav-dropdown-menu.is-open {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateX(-50%) translateY(0);
}

.dropdown-inner {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
}

.dropdown-col {
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.dropdown-heading {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-accent-2, #00d2ff);
    padding: 4px 6px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    margin-bottom: 4px;
}

.dropdown-link {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 6px 8px;
    border-radius: 8px;
    color: var(--color-text-primary, #f0f0f8);
    font-size: 12.5px;
    font-weight: 500;
    text-decoration: none;
    transition: background 0.15s ease, color 0.15s ease;
}

.dropdown-link:hover {
    background: rgba(108, 99, 255, 0.2);
    color: #ffffff;
    text-decoration: none;
}

.ratio-pill {
    display: inline-block;
    padding: 2px 6px;
    border-radius: 6px;
    font-size: 11px;
    font-weight: 700;
    font-family: var(--font-mono, monospace);
    background: rgba(255, 255, 255, 0.06);
    color: var(--color-accent-2, #00d2ff);
    border: 1px solid rgba(255, 255, 255, 0.1);
    white-space: nowrap;
}

.dropdown-footer {
    margin-top: 12px;
    padding-top: 10px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    text-align: center;
}

.dropdown-view-all {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--color-accent-2, #00d2ff);
    text-decoration: none;
    transition: color 0.15s;
}

.dropdown-view-all:hover {
    color: #ffffff;
    text-decoration: underline;
}



.header-actions {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Theme Toggle Button */
.btn-theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.14);
    color: var(--color-accent-2);
    cursor: pointer;
    transition: background var(--trans-fast), border-color var(--trans-fast), color var(--trans-fast), transform var(--trans-fast);
    flex-shrink: 0;
    padding: 0;
}

.btn-theme-toggle:hover {
    background: rgba(255, 255, 255, 0.12);
    border-color: var(--color-accent-1);
    color: #ffffff;
    transform: rotate(15deg) scale(1.05);
}

.btn-theme-toggle svg {
    transition: transform 0.3s ease, opacity 0.2s ease;
    display: block;
}

/* In Dark Mode: Show Sun icon (click to switch to light), hide Moon icon */
:root .theme-icon-moon,
[data-theme="dark"] .theme-icon-moon {
    display: none !important;
}
:root .theme-icon-sun,
[data-theme="dark"] .theme-icon-sun {
    display: block !important;
}

/* In Light Mode: Show Moon icon (click to switch to dark), hide Sun icon */
[data-theme="light"] .theme-icon-sun {
    display: none !important;
}
[data-theme="light"] .theme-icon-moon {
    display: block !important;
}

.btn-header-secondary {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--color-text-primary);
    padding: 7px 16px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: background var(--trans-fast), border-color var(--trans-fast);
}

.btn-header-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.25);
}

.btn-header-primary {
    background: linear-gradient(135deg, var(--color-accent-1), var(--color-accent-2));
    border: none;
    color: #ffffff;
    padding: 7px 18px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    box-shadow: 0 4px 14px rgba(108, 99, 255, 0.35);
    transition: opacity var(--trans-fast), transform var(--trans-fast);
}

.btn-header-primary:hover {
    opacity: 0.92;
    transform: translateY(-1px);
}

.mobile-toggle {
    display: none;
    background: transparent;
    border: none;
    color: var(--color-text-primary);
    cursor: pointer;
    padding: 6px;
}

@media (max-width: 991px) {
    .mobile-toggle { display: block; }
}


/* Mobile Nav Drawer */
.mobile-nav {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(10, 10, 26, 0.98);
    backdrop-filter: blur(28px);
    -webkit-backdrop-filter: blur(28px);
    padding: 20px 16px 40px;
    flex-direction: column;
    gap: 10px;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    z-index: 999;
}

.mobile-nav.is-open,
.mobile-nav.open {
    display: flex !important;
}

.mob-link {
    color: var(--color-text-primary, #f0f0f8);
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    padding: 10px 14px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: background 0.15s;
}

.mob-link:hover, .mob-link:active {
    background: rgba(108, 99, 255, 0.15);
    border-color: rgba(108, 99, 255, 0.3);
}

.mob-link-highlight {
    background: linear-gradient(135deg, rgba(108, 99, 255, 0.15), rgba(0, 210, 255, 0.15));
    border-color: rgba(0, 210, 255, 0.3);
    color: var(--color-accent-2, #00d2ff);
}

/* Mobile Tools Accordion Dropdown */
.mob-tools-dropdown {
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.02);
    overflow: hidden;
}

.mob-tools-btn {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 14px;
    background: rgba(255, 255, 255, 0.03);
    border: none;
    color: var(--color-text-primary, #f0f0f8);
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    text-align: left;
    font-family: inherit;
}

.mob-tools-btn-label {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.mob-count-badge {
    margin-left: auto;
    margin-right: 8px;
    padding: 2px 8px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 700;
    background: rgba(108, 99, 255, 0.2);
    color: var(--color-accent-2, #00d2ff);
    border: 1px solid rgba(108, 99, 255, 0.3);
}

.mob-chevron {
    transition: transform 0.25s ease;
}

.mob-tools-btn[aria-expanded="true"] .mob-chevron {
    transform: rotate(180deg);
}

.mob-tools-panel {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: 8px 10px 14px;
    max-height: 380px;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    background: rgba(0, 0, 0, 0.25);
}

.mob-tools-panel.is-open {
    display: flex;
}

.mob-sub-group-title {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--color-accent-2, #00d2ff);
    letter-spacing: 0.06em;
    padding: 8px 6px 4px;
}

.mob-tool-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 10px;
    border-radius: 8px;
    color: var(--color-text-primary, #f0f0f8);
    font-size: 13.5px;
    font-weight: 500;
    text-decoration: none;
    background: rgba(255, 255, 255, 0.02);
}

.mob-tool-row:hover, .mob-tool-row:active {
    background: rgba(108, 99, 255, 0.18);
    color: #ffffff;
}

.mob-tool-ratio {
    padding: 2px 6px;
    border-radius: 5px;
    font-size: 11px;
    font-weight: 700;
    font-family: var(--font-mono, monospace);
    background: rgba(255, 255, 255, 0.08);
    color: var(--color-accent-2, #00d2ff);
    white-space: nowrap;
}


/* HERO SECTION */
.hero {
    text-align: center;
    padding: 56px 0 36px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(108, 99, 255, 0.12);
    border: 1px solid rgba(108, 99, 255, 0.3);
    padding: 6px 16px;
    border-radius: 30px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--color-accent-2);
    margin-bottom: 20px;
}

.badge-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--color-accent-2);
    box-shadow: 0 0 8px var(--color-accent-2);
    animation: pulseDot 2s infinite;
}

@keyframes pulseDot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.4; transform: scale(0.8); }
}

.hero h1 {
    font-size: 40px;
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.03em;
    margin-bottom: 16px;
}

@media (min-width: 768px) {
    .hero h1 { font-size: 54px; }
}

.hero p {
    color: var(--color-text-secondary);
    max-width: 720px;
    margin: 0 auto 28px;
    font-size: 16.5px;
    line-height: 1.65;
}

/* Quick Presets Strip */
.preset-strip {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
}

.preset-label {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-text-tertiary);
    margin-right: 4px;
}

.preset-pill {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-secondary);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.preset-pill:hover {
    background: rgba(108, 99, 255, 0.2);
    border-color: var(--color-accent-1);
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(108, 99, 255, 0.25);
}

/* MAIN CALCULATOR CARD */
.calc-card {
    margin-top: 10px;
    margin-bottom: 48px;
    padding: 36px;
    background: rgba(16, 16, 38, 0.85);
}

.calc-header-row {
    display: flex;
    flex-direction: column;
    gap: 18px;
    margin-bottom: 28px;
    padding-bottom: 24px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

@media (min-width: 800px) {
    .calc-header-row {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
    }
}

.calc-title {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.01em;
    color: #ffffff;
}

.calc-subtitle {
    font-size: 13.5px;
    color: var(--color-text-secondary);
    margin-top: 4px;
}

/* Segmented Direction Switch */
.calc-type-switch {
    display: flex;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 14px;
    padding: 4px;
    gap: 4px;
}

.radio-tab {
    cursor: pointer;
    padding: 8px 18px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text-secondary);
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all var(--trans-fast);
}

.radio-tab input[type="radio"] {
    display: none;
}

.radio-tab:hover {
    color: #ffffff;
}

.radio-tab.active {
    background: var(--color-accent-1);
    color: #ffffff;
    box-shadow: 0 4px 16px rgba(108, 99, 255, 0.4);
}

/* Calculator Layout Grid */
.calc-layout-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 36px;
    align-items: start;
}

@media (min-width: 900px) {
    .calc-layout-grid {
        grid-template-columns: 1.15fr 0.85fr;
        gap: 40px;
    }
}

.calc-controls-col {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* Form Fields */
.calc-field {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.field-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.calc-field-label {
    font-size: 12px;
    font-weight: 700;
    text-transform: none;
    letter-spacing: 0.04em;
    color: var(--color-text-tertiary);
}

.field-hint {
    font-size: 11px;
    color: rgba(240, 240, 248, 0.5);
    font-family: var(--font-mono);
}

.calc-input-row {
    display: flex;
    gap: 10px;
}

.calc-input {
    flex: 1;
    height: 52px;
    background: var(--color-bg-input);
    border: 1.5px solid var(--color-border-subtle);
    border-radius: 12px;
    padding: 0 16px;
    color: var(--color-text-primary);
    font-family: var(--font-sans);
    font-size: 18px;
    font-weight: 600;
    outline: none;
    transition: all var(--trans-fast);
}

.calc-input:focus {
    background: var(--color-bg-input-focus);
    border-color: var(--color-accent-1);
    box-shadow: 0 0 0 3px rgba(108, 99, 255, 0.25);
}

.calc-select {
    width: 96px;
    height: 52px;
    background: var(--color-bg-input);
    border: 1.5px solid var(--color-border-subtle);
    border-radius: 12px;
    padding: 0 10px;
    color: var(--color-accent-2);
    font-family: var(--font-sans);
    font-size: 14px;
    font-weight: 700;
    outline: none;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.calc-select:focus {
    border-color: var(--color-accent-2);
    box-shadow: 0 0 0 3px rgba(0, 210, 255, 0.25);
}

.calc-select option {
    background: #121228;
    color: #ffffff;
}

/* Middle Swap Button & Conversion Indicator */
.conversion-indicator-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin: 4px 0;
}

.conv-line {
    flex: 1;
    height: 1px;
    background: rgba(255, 255, 255, 0.08);
}

.conv-swap-btn {
    background: rgba(18, 18, 42, 0.9);
    border: 1.5px solid var(--color-accent-1);
    color: var(--color-accent-2);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 700;
    font-family: var(--font-mono);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    box-shadow: 0 0 12px rgba(108, 99, 255, 0.3);
    transition: all var(--trans-fast);
}

.conv-swap-btn:hover {
    background: var(--color-accent-1);
    color: #ffffff;
    transform: scale(1.05);
}

/* Centigram Output Field */
.calc-result-label {
    font-size: 12px;
    font-weight: 700;
    text-transform: none;
    letter-spacing: 0.04em;
    color: var(--color-accent-2);
}

.result-formula-badge {
    background: rgba(0, 210, 255, 0.15);
    color: var(--color-accent-2);
    padding: 3px 8px;
    border-radius: 6px;
    font-size: 11px;
    font-family: var(--font-mono);
    font-weight: 600;
}

.calc-result-input {
    background: rgba(0, 0, 0, 0.35) !important;
    border-color: var(--color-accent-2) !important;
    color: var(--color-accent-2) !important;
    font-size: 22px !important;
    font-weight: 800 !important;
    letter-spacing: 0.02em;
    box-shadow: 0 0 15px rgba(0, 210, 255, 0.25);
}

.calc-result-select {
    width: 105px;
    border-color: var(--color-accent-2);
    font-size: 14px;
}

.btn-copy {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    color: var(--color-text-secondary);
    border-radius: 12px;
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.btn-copy:hover {
    background: rgba(0, 210, 255, 0.2);
    color: #ffffff;
    border-color: var(--color-accent-2);
}

/* Multi-Unit Conversion Strip */
.conversions-strip {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    padding-top: 10px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

@media (min-width: 600px) {
    .conversions-strip { grid-template-columns: repeat(4, 1fr); }
}

.conv-item {
    background: rgba(0, 0, 0, 0.25);
    padding: 8px 10px;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
}

.conv-lbl {
    font-size: 10.5px;
    font-weight: 600;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
}

.conv-val {
    font-size: 13.5px;
    font-weight: 700;
    color: #ffffff;
    font-family: var(--font-mono);
}

/* Action Bar */
.calc-action-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 6px;
}

.btn-reset {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-secondary);
    padding: 8px 18px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all var(--trans-fast);
}

.btn-reset:hover {
    background: rgba(255, 255, 255, 0.12);
    color: #ffffff;
}

.live-calc-status {
    font-size: 11.5px;
    color: var(--color-success);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
}

.calc-visual-col {
    display: flex;
    flex-direction: column;
    width: 100%;
}

.live-diagram-card {
    background: rgba(10, 10, 26, 0.6);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 20px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    width: 100%;
    box-sizing: border-box;
}

.diagram-tag {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-accent-2);
    background: rgba(0, 210, 255, 0.1);
    padding: 4px 12px;
    border-radius: 20px;
    margin-bottom: 14px;
}

.calc-diagram {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.main-calc-svg {
    width: 100%;
    max-width: 290px;
    height: auto;
    filter: drop-shadow(0 8px 24px rgba(0, 0, 0, 0.5));
}

.calc-formula {
    margin-top: 14px;
    font-size: 13.5px;
    font-weight: 700;
    font-family: var(--font-mono);
    color: var(--color-accent-2);
    background: rgba(108, 99, 255, 0.12);
    padding: 8px 16px;
    border-radius: 12px;
    border: 1px solid rgba(108, 99, 255, 0.25);
    width: 100%;
    box-sizing: border-box;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    word-break: break-word;
    line-height: 1.4;
}

.interactive-diagram-hint {
    margin-top: 14px;
    font-size: 12px;
    color: var(--color-text-tertiary);
    text-align: center;
    line-height: 1.5;
}

/* GENERAL CONTENT SECTIONS */
.content-section {
    margin-top: 80px;
    position: relative;
}

.section-badge {
    font-size: 11.5px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-accent-1);
    margin-bottom: 8px;
}

.section-title {
    font-size: 28px;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 24px;
    color: #ffffff;
}

@media (min-width: 768px) {
    .section-title { font-size: 34px; }
}

.section-lead-text {
    color: var(--color-text-secondary);
    font-size: 16px;
    max-width: 720px;
    margin-bottom: 32px;
}

.content-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 36px;
    align-items: start;
}

@media (min-width: 850px) {
    .content-grid {
        grid-template-columns: 1.15fr 0.85fr;
        gap: 40px;
    }
}

.content-text p {
    color: var(--color-text-secondary);
    font-size: 15.5px;
    line-height: 1.75;
    margin-bottom: 16px;
}

.content-text strong {
    color: #ffffff;
}

.fancy-bullet-list {
    list-style: none;
    margin: 16px 0 20px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.fancy-bullet-list li {
    position: relative;
    padding-left: 24px;
    color: var(--color-text-secondary);
    font-size: 14.5px;
}

.fancy-bullet-list li::before {
    content: "▹";
    position: absolute;
    left: 0;
    color: var(--color-accent-2);
    font-size: 16px;
    font-weight: bold;
}

/* Formula Callouts & Highlights */
.formula-callout {
    background: rgba(108, 99, 255, 0.1);
    border: 1px solid rgba(108, 99, 255, 0.3);
    border-radius: 16px;
    padding: 20px;
    text-align: center;
    margin: 20px 0;
}

.formula-math-display {
    font-size: 26px;
    font-weight: 800;
    font-family: var(--font-mono);
    color: var(--color-accent-2);
    letter-spacing: 0.03em;
}

.callout-subtext {
    display: block;
    margin-top: 8px;
    font-size: 12.5px;
    color: var(--color-text-tertiary);
    font-weight: 500;
}

.formula-alt {
    background: rgba(0, 0, 0, 0.25);
    border-left: 3px solid var(--color-accent-2);
    padding: 12px 18px;
    margin: 16px 0;
    border-radius: 0 10px 10px 0;
    font-family: var(--font-mono);
    color: #ffffff;
    font-size: 14.5px;
}

.fancy-quote {
    background: rgba(108, 99, 255, 0.08);
    border-left: 3px solid var(--color-accent-1);
    padding: 14px 20px;
    border-radius: 0 12px 12px 0;
    color: #e0e0ff;
    font-style: italic;
    font-size: 15px;
    margin: 18px 0;
}

/* 3-Step Walkthrough Cards */
.steps-container {
    display: flex;
    flex-direction: column;
    gap: 14px;
    margin: 20px 0;
}

.step-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 14px;
    padding: 16px;
    display: flex;
    gap: 16px;
    align-items: flex-start;
    transition: all var(--trans-fast);
}

.step-card:hover {
    background: rgba(108, 99, 255, 0.1);
    border-color: rgba(108, 99, 255, 0.3);
}

.step-number {
    font-size: 18px;
    font-weight: 800;
    color: var(--color-accent-1);
    background: rgba(108, 99, 255, 0.15);
    width: 38px;
    height: 38px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.step-title {
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 4px;
    color: #ffffff;
}

.step-text {
    font-size: 13.5px;
    color: var(--color-text-secondary);
    line-height: 1.5;
}

.worked-example-box {
    background: rgba(0, 210, 255, 0.06);
    border: 1px solid rgba(0, 210, 255, 0.2);
    border-radius: 14px;
    padding: 18px;
    margin-top: 20px;
    font-size: 14.5px;
    color: var(--color-text-secondary);
}

.example-math {
    margin-top: 8px;
    color: var(--color-accent-2);
    font-family: var(--font-mono);
    font-size: 14.5px;
    font-weight: 600;
}

/* Variable list */
.variable-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 18px 0;
}

.var-item {
    display: flex;
    align-items: center;
    gap: 14px;
    background: rgba(255, 255, 255, 0.03);
    padding: 10px 14px;
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.06);
}

.var-symbol {
    font-size: 17px;
    font-weight: 800;
    color: var(--color-accent-2);
    font-family: var(--font-mono);
    min-width: 48px;
}

.var-desc {
    font-size: 13.5px;
    color: var(--color-text-secondary);
}

/* INTERACTIVE BOXES (RIGHT COLUMN) */
.interactive-box {
    background: var(--color-bg-card);
    backdrop-filter: blur(24px) saturate(1.4);
    -webkit-backdrop-filter: blur(24px) saturate(1.4);
    border: 1px solid var(--color-bg-card-border);
    border-radius: 24px;
    padding: 28px;
    display: flex;
    flex-direction: column;
    align-items: center;
    box-shadow: var(--shadow-card);
}

.interactive-header {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.interactive-label {
    font-size: 12px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--color-accent-2);
}

.interactive-status-pill {
    background: rgba(0, 210, 255, 0.12);
    color: var(--color-accent-2);
    font-size: 11px;
    font-weight: 700;
    padding: 3px 10px;
    border-radius: 20px;
}

.interactive-hint {
    font-size: 11px;
    color: var(--color-text-tertiary);
}

.diagram-svg {
    width: 100%;
    max-width: 300px;
    height: auto;
}

.interactive-caption {
    font-size: 13px;
    color: var(--color-text-secondary);
    text-align: center;
    margin-top: 18px;
    line-height: 1.55;
}

/* 100-PARTICLE MATRIX GRID STYLES */
.particle-matrix-wrapper {
    width: 100%;
    display: flex;
    justify-content: center;
    margin-bottom: 16px;
    background: rgba(0, 0, 0, 0.35);
    padding: 20px;
    border-radius: 16px;
    border: 1px solid rgba(108, 99, 255, 0.2);
}

.particle-matrix-grid {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    grid-template-rows: repeat(10, 1fr);
    gap: 6px;
    width: 100%;
    max-width: 250px;
    aspect-ratio: 1 / 1;
}

.cg-dot-unit {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    transition: all 0.25s ease;
    cursor: pointer;
}

.cg-dot-unit.active {
    background: var(--color-accent-2);
    box-shadow: 0 0 8px var(--color-accent-2), 0 0 14px rgba(0, 210, 255, 0.4);
    transform: scale(1.15);
}

/* Fluid / Particle Range Controls */
.fluid-controls {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 12px;
    background: rgba(0, 0, 0, 0.25);
    padding: 16px;
    border-radius: 16px;
}

.fluid-slider-label {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--color-text-secondary);
}

.range-slider {
    width: 100%;
    accent-color: var(--color-accent-2);
    height: 6px;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 6px;
}

.fluid-btn-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.btn-micro {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-secondary);
    padding: 5px 12px;
    border-radius: 8px;
    font-size: 11.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.btn-micro:hover {
    background: rgba(108, 99, 255, 0.25);
    border-color: var(--color-accent-1);
    color: #ffffff;
}

.pulse-btn {
    background: rgba(0, 210, 255, 0.15);
    border-color: var(--color-accent-2);
    color: var(--color-accent-2);
}

/* 3-CONVERSION MODES SELECTOR */
.cyl-types-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    width: 100%;
    margin-bottom: 20px;
}

.cyl-type-item {
    cursor: pointer;
    background: rgba(255, 255, 255, 0.03);
    border: 1.5px solid transparent;
    border-radius: 14px;
    padding: 12px 6px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    transition: all var(--trans-fast);
}

.cyl-type-item:hover {
    background: rgba(108, 99, 255, 0.1);
    border-color: rgba(108, 99, 255, 0.3);
}

.cyl-type-item.active {
    background: rgba(108, 99, 255, 0.2);
    border-color: var(--color-accent-1);
    box-shadow: 0 4px 20px rgba(108, 99, 255, 0.25);
    transform: translateY(-2px);
}

.cyl-type-svg {
    width: 100%;
    max-width: 75px;
    height: auto;
    opacity: 0.85;
}

.cyl-type-item.active .cyl-type-svg { opacity: 1; }

.cyl-type-name {
    font-size: 11px;
    font-weight: 700;
    text-align: center;
    color: var(--color-text-secondary);
    line-height: 1.25;
}

.cyl-type-item.active .cyl-type-name {
    color: #ffffff;
}

.cyl-types-info {
    width: 100%;
    background: rgba(108, 99, 255, 0.08);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 16px;
    padding: 18px;
    text-align: center;
}

.cyl-types-title {
    font-size: 14px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 4px;
}

.cyl-types-formula {
    font-size: 20px;
    font-weight: 800;
    font-family: var(--font-mono);
    color: var(--color-accent-2);
    margin-bottom: 8px;
}

.cyl-types-desc {
    font-size: 13px;
    color: var(--color-text-secondary);
    line-height: 1.5;
    margin-bottom: 14px;
}

.btn-type-load {
    background: rgba(108, 99, 255, 0.2);
    border: 1px solid var(--color-accent-1);
    color: #ffffff;
    padding: 6px 16px;
    border-radius: 10px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.btn-type-load:hover {
    background: var(--color-accent-1);
}

/* FORMULA TOKEN INSPECTOR */
.formula-display {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
    padding: 20px 0;
}

.formula-part {
    font-size: 38px;
    font-weight: 800;
    font-family: var(--font-mono);
    color: #ffffff;
    padding: 4px 12px;
    border-radius: 10px;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.formula-part:hover, .formula-part.formula-active {
    transform: scale(1.15);
}

#fp-cg:hover, #fp-cg.formula-active {
    color: var(--color-accent-2);
    background: rgba(0, 210, 255, 0.2);
}

#fp-g:hover, #fp-g.formula-active {
    color: #6c63ff;
    background: rgba(108, 99, 255, 0.2);
}

#fp-factor:hover, #fp-factor.formula-active {
    color: #00d2ff;
    background: rgba(0, 210, 255, 0.2);
}

.formula-op {
    font-size: 26px;
    color: var(--color-text-tertiary);
}

.formula-inspector-card {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    padding: 16px;
    width: 100%;
    min-height: 95px;
    text-align: center;
}

.inspector-token-title {
    font-size: 14px;
    font-weight: 700;
    color: var(--color-accent-2);
    margin-bottom: 6px;
}

.formula-desc {
    font-size: 13.5px;
    color: var(--color-text-secondary);
    line-height: 1.5;
}

.formula-quick-tester {
    margin-top: 14px;
    font-size: 12.5px;
    background: rgba(255, 255, 255, 0.03);
    padding: 8px 14px;
    border-radius: 8px;
    display: flex;
    gap: 8px;
    width: 100%;
    justify-content: center;
}

.tester-lbl { color: var(--color-text-tertiary); font-weight: 600; }
.tester-val { color: var(--color-accent-3); font-family: var(--font-mono); }

/* DIGITAL LAB MICRO-BALANCE */
.lab-scale-graphic {
    width: 100%;
    display: flex;
    justify-content: center;
    margin-bottom: 12px;
}

.hollow-sliders-group {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 10px;
    background: rgba(0, 0, 0, 0.25);
    padding: 16px;
    border-radius: 14px;
}

.slider-row {
    display: flex;
    align-items: center;
    gap: 12px;
}

.sl-label {
    width: 130px;
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-secondary);
    flex-shrink: 0;
}

.sl-val {
    width: 65px;
    font-size: 13px;
    font-family: var(--font-mono);
    color: var(--color-accent-2);
    font-weight: 700;
    text-align: right;
}

.hollow-stats-strip {
    display: flex;
    justify-content: space-between;
    width: 100%;
    margin-top: 14px;
    background: rgba(108, 99, 255, 0.08);
    padding: 10px 14px;
    border-radius: 10px;
    font-size: 12px;
    color: var(--color-text-secondary);
}

.hollow-stats-strip strong {
    color: var(--color-accent-2);
}

/* DECIMAL SHIFTER STAGE */
.decimal-shift-stage {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid rgba(108, 99, 255, 0.3);
    border-radius: 16px;
    padding: 24px;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 16px;
}

.shift-digit-row {
    display: flex;
    align-items: baseline;
    gap: 6px;
    font-size: 36px;
    font-weight: 800;
    font-family: var(--font-mono);
}

.shift-digit {
    color: #ffffff;
}

.shift-dot-glow {
    color: var(--color-accent-2);
    text-shadow: 0 0 12px var(--color-accent-2);
    font-size: 42px;
    animation: pulseDot 1.5s infinite;
}

.shift-unit-label {
    font-size: 16px;
    color: var(--color-accent-3);
    font-weight: 600;
    margin-left: 12px;
    font-family: var(--font-sans);
}

.oblique-toggle-container {
    display: flex;
    gap: 10px;
    margin-bottom: 16px;
    width: 100%;
}

.oblique-toggle-btn {
    flex: 1;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--color-text-secondary);
    padding: 8px 12px;
    border-radius: 10px;
    font-size: 12.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
    text-align: center;
}

.oblique-toggle-btn.active {
    background: rgba(0, 210, 255, 0.18);
    border-color: var(--color-accent-2);
    color: var(--color-accent-2);
}

.tilt-slider-container {
    width: 100%;
    background: rgba(0, 0, 0, 0.25);
    padding: 16px;
    border-radius: 14px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.tilt-slider-label {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--color-text-secondary);
}

.tilt-readouts {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
    font-size: 12px;
    color: var(--color-text-tertiary);
}

/* UNIT HIERARCHY PROGRESS BARS */
.cone-visual {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 16px;
}

.cone-bar-group {
    display: flex;
    align-items: center;
    gap: 12px;
}

.cone-bar-label {
    width: 90px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--color-text-secondary);
    text-align: right;
}

.cone-bar-track {
    flex: 1;
    height: 28px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 8px;
    overflow: hidden;
}

.cone-bar {
    height: 100%;
    border-radius: 8px;
    transition: width 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.cone-bar-cyl {
    width: 100%;
    background: linear-gradient(90deg, #6c63ff, #a78bfa);
}

.cone-bar-cone {
    background: linear-gradient(90deg, #00d2ff, #00a3cc);
}

.sphere-bar-sph {
    background: linear-gradient(90deg, #a78bfa, #6c63ff);
}

.cone-bar-val {
    width: 110px;
    font-size: 12px;
    font-weight: 700;
    font-family: var(--font-mono);
    color: #ffffff;
}

.cone-slider-wrap {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 14px;
    background: rgba(0, 0, 0, 0.25);
    padding: 14px;
    border-radius: 12px;
    margin-bottom: 12px;
}

.cone-slider-label {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-secondary);
}

.cone-slider-val {
    font-size: 14px;
    font-weight: 800;
    color: var(--color-accent-2);
    min-width: 90px;
    text-align: right;
}

.cone-pills-row {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    justify-content: center;
}

/* GRAVITY COMPARATOR */
.sphere-input-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 16px;
    background: rgba(0, 0, 0, 0.25);
    padding: 10px 16px;
    border-radius: 12px;
    width: 100%;
}

.sphere-input-row label {
    font-size: 12.5px;
    font-weight: 600;
    color: var(--color-text-secondary);
}

.sphere-input-row .calc-input {
    max-width: 110px;
    height: 40px;
    font-size: 15px;
}

.unit-tag {
    font-size: 13px;
    color: var(--color-text-tertiary);
    font-weight: 600;
}

.sphere-bars {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.sphere-bar-group {
    display: flex;
    align-items: center;
    gap: 12px;
}

.sphere-bar-label {
    width: 120px;
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-secondary);
    text-align: right;
}

.sphere-bar-track {
    flex: 1;
    height: 24px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 6px;
    overflow: hidden;
}

.sphere-bar {
    height: 100%;
    border-radius: 6px;
    transition: width 0.4s ease;
}

.sphere-bar-cyl { background: linear-gradient(90deg, #6c63ff, #a78bfa); }
.sphere-bar-gap { background: rgba(255, 255, 255, 0.25); }

.sphere-bar-val {
    width: 100px;
    font-size: 12px;
    font-weight: 700;
    font-family: var(--font-mono);
    color: #ffffff;
}

/* 23 SPECIALIZED TOOLS GRID */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
}

@media (min-width: 600px) {
    .tools-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (min-width: 900px) {
    .tools-grid { grid-template-columns: repeat(4, 1fr); }
}

@media (min-width: 1100px) {
    .tools-grid { grid-template-columns: repeat(5, 1fr); }
}

.tool-card {
    background: rgba(18, 18, 42, 0.7);
    border: 1px solid rgba(108, 99, 255, 0.2);
    border-radius: 16px;
    padding: 18px 12px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.tool-card:hover {
    background: rgba(108, 99, 255, 0.22);
    border-color: var(--color-accent-1);
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(108, 99, 255, 0.3);
}

.tool-icon {
    font-size: 26px;
}

.tool-name {
    font-size: 13px;
    font-weight: 700;
    color: var(--color-text-primary);
    text-align: center;
    line-height: 1.3;
}

.tool-tag {
    font-size: 10.5px;
    color: var(--color-accent-2);
    background: rgba(0, 210, 255, 0.1);
    padding: 2px 8px;
    border-radius: 6px;
    font-weight: 600;
}

/* REFERENCE DATA TABLE */
.table-card {
    padding: 0;
    overflow: hidden;
}

.table-responsive {
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
    text-align: left;
}

.data-table th {
    background: rgba(0, 0, 0, 0.35);
    padding: 16px 20px;
    font-size: 11.5px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-text-tertiary);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.data-table td {
    padding: 14px 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--color-text-secondary);
}

.data-table tr:hover td {
    background: rgba(255, 255, 255, 0.03);
}

.data-table .vol {
    color: var(--color-accent-2);
    font-weight: 700;
    font-family: var(--font-mono);
}

.btn-table-load {
    background: rgba(108, 99, 255, 0.15);
    border: 1px solid var(--color-accent-1);
    color: #ffffff;
    padding: 5px 12px;
    border-radius: 8px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.btn-table-load:hover {
    background: var(--color-accent-1);
}

/* FAQ SECTION */
.section-gap {
    margin-top: 80px;
}

.faq-search-box {
    margin-bottom: 24px;
}

.faq-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.faq-item {
    padding: 0;
    border-radius: 16px;
    overflow: hidden;
    transition: border-color var(--trans-fast);
}

.faq-item[open] {
    border-color: rgba(108, 99, 255, 0.5);
    background: rgba(20, 20, 48, 0.85);
}

.faq-item summary {
    padding: 18px 24px;
    cursor: pointer;
    font-size: 15.5px;
    font-weight: 600;
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    list-style: none;
    user-select: none;
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-chevron {
    color: var(--color-accent-2);
    transition: transform var(--trans-fast);
    flex-shrink: 0;
    margin-left: 12px;
}

.faq-item[open] .faq-chevron {
    transform: rotate(180deg);
}

.faq-answer {
    padding: 0 24px 22px;
    color: var(--color-text-secondary);
    font-size: 14.5px;
    line-height: 1.7;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding-top: 16px;
}

/* FOOTER */
.site-footer {
    background: rgba(7, 7, 20, 0.95);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    margin-top: 100px;
    padding: 64px 0 36px;
}

.footer-inner {
    max-width: 1220px;
    margin: 0 auto;
    padding: 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 36px;
    margin-bottom: 48px;
}

@media (min-width: 768px) {
    .footer-grid {
        grid-template-columns: 1.4fr 0.9fr 1.1fr 1fr;
    }
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: #ffffff;
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 14px;
}

.footer-desc {
    font-size: 13.5px;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: 20px;
}

.footer-social {
    display: flex;
    gap: 10px;
}

.footer-social-link {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--color-text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all var(--trans-fast);
}

.footer-social-link:hover {
    background: rgba(108, 99, 255, 0.3);
    border-color: var(--color-accent-1);
    color: var(--color-accent-2);
    transform: translateY(-2px);
}

.footer-heading {
    font-size: 12px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: #ffffff;
    margin-bottom: 18px;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-links a {
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: 13.5px;
    transition: color var(--trans-fast);
}

.footer-links a:hover {
    color: var(--color-accent-2);
}

.footer-contact-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--color-text-secondary);
}

.footer-langs {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.lang-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-secondary);
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 11px;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.lang-btn:hover, .lang-btn.active {
    background: var(--color-accent-1);
    border-color: var(--color-accent-1);
    color: #ffffff;
}

.footer-copy {
    text-align: center;
    font-size: 13px;
    color: var(--color-text-tertiary);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    padding-top: 24px;
}

/* FLOATING BACK TO TOP */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 46px;
    height: 46px;
    border-radius: 12px;
    background: rgba(18, 18, 42, 0.85);
    backdrop-filter: blur(12px);
    border: 1px solid var(--color-accent-1);
    color: var(--color-accent-2);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(14px);
    transition: all var(--trans-smooth);
    z-index: 90;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--color-accent-1);
    color: #ffffff;
    box-shadow: 0 6px 24px rgba(108, 99, 255, 0.5);
}

/* MODALS */
.modal-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(5, 5, 15, 0.8);
    backdrop-filter: blur(14px);
    z-index: 1000;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.modal-backdrop.is-open {
    display: flex;
}

.modal-card {
    max-width: 540px;
    width: 100%;
    background: rgba(18, 18, 44, 0.95);
    border: 1px solid rgba(108, 99, 255, 0.4);
    animation: modalPop 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalPop {
    from { opacity: 0; transform: scale(0.92); }
    to { opacity: 1; transform: scale(1); }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding-bottom: 14px;
}

.modal-header h2 {
    font-size: 20px;
    font-weight: 700;
    color: #ffffff;
}

.modal-close {
    background: transparent;
    border: none;
    color: var(--color-text-secondary);
    font-size: 28px;
    line-height: 1;
    cursor: pointer;
}

.modal-close:hover { color: #ffffff; }

.modal-body p {
    font-size: 14.5px;
    color: var(--color-text-secondary);
    line-height: 1.65;
    margin-bottom: 14px;
}

.about-stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-top: 20px;
    text-align: center;
}

.astat {
    background: rgba(255, 255, 255, 0.04);
    border-radius: 12px;
    padding: 12px;
}

.astat-num {
    display: block;
    font-size: 20px;
    font-weight: 800;
    color: var(--color-accent-2);
}

.astat-lbl {
    font-size: 11px;
    color: var(--color-text-tertiary);
    font-weight: 600;
}

/* Contact Form */
.contact-form {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.contact-form textarea {
    height: 110px;
    padding-top: 12px;
    resize: vertical;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-accent-1), var(--color-accent-2));
    border: none;
    color: #ffffff;
    height: 48px;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    transition: opacity var(--trans-fast);
}

.btn-primary:hover { opacity: 0.9; }

/* TOAST NOTIFICATION */
.toast {
    position: fixed;
    top: 24px;
    right: 24px;
    background: rgba(18, 18, 44, 0.95);
    border: 1px solid var(--color-accent-2);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.6), 0 0 15px rgba(0, 210, 255, 0.3);
    color: #ffffff;
    padding: 12px 20px;
    border-radius: 12px;
    font-size: 13.5px;
    font-weight: 600;
    z-index: 2000;
    opacity: 0;
    transform: translateY(-16px);
    transition: all var(--trans-smooth);
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

/* UTILITIES */
.hidden-field { display: none !important; }
.hidden { display: none !important; }

/* ==========================================================================
   COMPETITOR BEATER ENHANCEMENTS:
   - Live Calculation Summary Card
   - Interactive Gram <-> Centigram Conversion Table & Generator
   - Dynamic Step-by-Step Problem Solver
   - 18 Popular Weight & Mass Conversions Interactive Grid
   - Universal Mass Explorer (60+ Units with Live Converted Values)
   ========================================================================== */

/* Main Calculator Instant Summary Box */
.calc-result-summary-box {
    margin-top: 16px;
    background: linear-gradient(135deg, rgba(108, 99, 255, 0.12), rgba(0, 210, 255, 0.08));
    border: 1px solid rgba(0, 210, 255, 0.3);
    border-radius: 14px;
    padding: 14px 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    flex-wrap: wrap;
}

.calc-summary-left {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.calc-summary-main {
    font-size: 1.15rem;
    font-weight: 800;
    color: #ffffff;
    font-family: var(--font-mono);
    display: flex;
    align-items: center;
    gap: 8px;
}

.calc-summary-main .accent {
    color: var(--color-accent-2);
}

.calc-summary-sub {
    font-size: 0.85rem;
    color: var(--color-text-secondary);
}

.calc-action-btns-group {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}

.btn-calc-convert {
    background: linear-gradient(135deg, var(--color-accent-1), var(--color-accent-2));
    border: none;
    color: #ffffff;
    padding: 9px 20px;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all var(--trans-fast);
    box-shadow: 0 4px 15px rgba(108, 99, 255, 0.35);
}

.btn-calc-convert:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(0, 210, 255, 0.45);
}

.btn-calc-clear {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-text-secondary);
    padding: 9px 16px;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all var(--trans-fast);
}

.btn-calc-clear:hover {
    background: rgba(239, 68, 68, 0.15);
    border-color: rgba(239, 68, 68, 0.4);
    color: #fca5a5;
}

/* SECTION: CONVERSION TABLE & GENERATOR */
.conv-table-controls-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.conv-table-tabs {
    display: flex;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--color-border-subtle);
    border-radius: 12px;
    padding: 4px;
    gap: 4px;
}

.conv-table-tab {
    background: transparent;
    border: none;
    color: var(--color-text-secondary);
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 13.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.conv-table-tab.active {
    background: var(--color-accent-1);
    color: #ffffff;
    box-shadow: 0 2px 10px rgba(108, 99, 255, 0.3);
}

.conv-table-actions {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.conv-table-search-input {
    background: var(--color-bg-input);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-text-primary);
    padding: 8px 14px;
    border-radius: 10px;
    font-size: 13.5px;
    outline: none;
    min-width: 200px;
    transition: border-color var(--trans-fast);
}

.conv-table-search-input:focus {
    border-color: var(--color-accent-2);
}

.btn-toggle-generator {
    background: rgba(0, 210, 255, 0.1);
    border: 1px solid rgba(0, 210, 255, 0.3);
    color: var(--color-accent-2);
    padding: 8px 16px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all var(--trans-fast);
}

.btn-toggle-generator:hover {
    background: rgba(0, 210, 255, 0.2);
}

/* Custom Table Generator Form */
.custom-generator-drawer {
    background: rgba(14, 14, 36, 0.7);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 14px;
    padding: 16px 20px;
    margin-bottom: 20px;
    display: none;
}

.custom-generator-drawer.open {
    display: block;
    animation: fadeIn 0.3s ease;
}

.custom-gen-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)) auto;
    gap: 14px;
    align-items: flex-end;
}

.gen-field {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.gen-field label {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-secondary);
}

.gen-field input {
    background: var(--color-bg-input);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-text-primary);
    padding: 8px 12px;
    border-radius: 8px;
    font-size: 14px;
    font-family: var(--font-mono);
}

.btn-generate-table {
    background: var(--color-accent-1);
    border: none;
    color: #ffffff;
    padding: 9px 18px;
    border-radius: 8px;
    font-size: 13.5px;
    font-weight: 700;
    cursor: pointer;
    height: 38px;
}

/* SECTION: STEP-BY-STEP LIVE SOLVER */
.live-solver-box {
    background: rgba(18, 18, 44, 0.8);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 18px;
    padding: 24px;
    margin-top: 24px;
}

.solver-input-row {
    display: flex;
    gap: 14px;
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.solver-input-group {
    display: flex;
    align-items: center;
    gap: 8px;
    flex: 1;
    min-width: 220px;
}

.solver-input-group label {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-text-secondary);
    white-space: nowrap;
}

.solver-val-input {
    background: var(--color-bg-input);
    border: 1px solid var(--color-border-subtle);
    color: #ffffff;
    padding: 8px 14px;
    border-radius: 10px;
    font-size: 15px;
    font-family: var(--font-mono);
    width: 130px;
}

.solver-dir-select {
    background: rgba(22, 22, 50, 0.9);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-text-primary);
    padding: 8px 12px;
    border-radius: 10px;
    font-size: 13.5px;
}

.solver-steps-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.solver-step-card {
    background: rgba(255, 255, 255, 0.03);
    border-left: 3px solid var(--color-accent-2);
    border-radius: 0 10px 10px 0;
    padding: 12px 16px;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.solver-step-card.step-final {
    border-left-color: var(--color-success);
    background: rgba(16, 185, 129, 0.06);
}

.solver-step-num {
    font-size: 11px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--color-accent-2);
}

.solver-step-num.final-num {
    color: var(--color-success);
}

.solver-step-body {
    font-size: 14px;
    color: var(--color-text-primary);
}

.solver-math-code {
    display: inline-block;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 6px;
    padding: 3px 8px;
    font-family: var(--font-mono);
    font-weight: 700;
    color: var(--color-accent-2);
    margin-top: 4px;
}

/* SECTION: POPULAR WEIGHT & MASS CONVERSIONS HUB */
.popular-conv-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 16px;
    margin-top: 24px;
}

.pop-conv-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border-subtle);
    border-radius: 14px;
    padding: 18px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    transition: all var(--trans-smooth);
    position: relative;
    overflow: hidden;
}

.pop-conv-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--color-accent-1), transparent);
    opacity: 0;
    transition: opacity var(--trans-fast);
}

.pop-conv-card:hover {
    border-color: rgba(108, 99, 255, 0.4);
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
}

.pop-conv-card:hover::before {
    opacity: 1;
}

.pop-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.pop-card-title {
    font-size: 15px;
    font-weight: 700;
    color: #ffffff;
    display: flex;
    align-items: center;
    gap: 6px;
}

.pop-card-badge {
    font-size: 11px;
    font-weight: 600;
    background: rgba(108, 99, 255, 0.18);
    color: var(--color-accent-3);
    padding: 3px 8px;
    border-radius: 6px;
}

.pop-card-calc-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.pop-card-input {
    background: var(--color-bg-input);
    border: 1px solid var(--color-border-subtle);
    color: #ffffff;
    padding: 6px 10px;
    border-radius: 8px;
    font-size: 13.5px;
    font-family: var(--font-mono);
    width: 80px;
}

.pop-card-unit-lbl {
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text-secondary);
}

.pop-card-arrow {
    color: var(--color-accent-2);
    font-weight: 700;
    padding: 0 4px;
}

.pop-card-output {
    font-size: 13.5px;
    font-family: var(--font-mono);
    font-weight: 700;
    color: var(--color-accent-2);
    background: rgba(0, 210, 255, 0.08);
    border: 1px solid rgba(0, 210, 255, 0.2);
    padding: 6px 10px;
    border-radius: 8px;
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.pop-card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 4px;
    font-size: 12px;
    color: var(--color-text-tertiary);
}

.pop-card-btn-load {
    background: none;
    border: none;
    color: var(--color-accent-3);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    padding: 2px 4px;
    border-radius: 4px;
    transition: color var(--trans-fast);
}

.pop-card-btn-load:hover {
    color: #ffffff;
    text-decoration: underline;
}

/* SECTION: UNIVERSAL MASS & WEIGHT EXPLORER (60+ UNITS) */
.universal-explorer-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border-subtle);
    border-radius: 20px;
    padding: 28px;
    margin-top: 24px;
}

.explorer-filter-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 24px;
    padding-bottom: 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.explorer-category-pills {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.explorer-cat-pill {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-text-secondary);
    padding: 7px 14px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}

.explorer-cat-pill.active {
    background: linear-gradient(135deg, var(--color-accent-1), var(--color-accent-2));
    border-color: transparent;
    color: #ffffff;
    box-shadow: 0 4px 15px rgba(108, 99, 255, 0.3);
}

.explorer-search-input {
    background: var(--color-bg-input);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-text-primary);
    padding: 9px 16px;
    border-radius: 12px;
    font-size: 14px;
    outline: none;
    min-width: 240px;
    transition: border-color var(--trans-fast);
}

.explorer-search-input:focus {
    border-color: var(--color-accent-2);
}

.explorer-live-banner {
    background: rgba(0, 210, 255, 0.06);
    border: 1px solid rgba(0, 210, 255, 0.2);
    border-radius: 10px;
    padding: 10px 16px;
    margin-bottom: 20px;
    font-size: 13px;
    color: var(--color-accent-2);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
}

.universal-units-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 14px;
    max-height: 720px;
    overflow-y: auto;
    padding-right: 6px;
}

.unit-item-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 14px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    transition: all var(--trans-fast);
}

.unit-item-card:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(0, 210, 255, 0.3);
    transform: translateY(-2px);
}

.unit-card-top {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 6px;
}

.unit-card-name {
    font-size: 14px;
    font-weight: 700;
    color: #ffffff;
}

.unit-card-sym {
    font-size: 11px;
    font-family: var(--font-mono);
    color: var(--color-accent-3);
    background: rgba(108, 99, 255, 0.15);
    padding: 2px 6px;
    border-radius: 4px;
    white-space: nowrap;
}

.unit-card-calc-val {
    font-size: 15px;
    font-weight: 800;
    font-family: var(--font-mono);
    color: var(--color-accent-2);
    word-break: break-all;
}

.unit-card-ratio {
    font-size: 11px;
    color: var(--color-text-tertiary);
    font-family: var(--font-mono);
}

.unit-card-btn-apply {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-secondary);
    border-radius: 6px;
    padding: 4px 8px;
    font-size: 11.5px;
    font-weight: 600;
    cursor: pointer;
    align-self: flex-start;
    transition: all var(--trans-fast);
    margin-top: 4px;
}

.unit-card-btn-apply:hover {
    background: var(--color-accent-1);
    border-color: var(--color-accent-1);
    color: #ffffff;
}

@media (max-width: 768px) {
    .conv-table-controls-row {
        flex-direction: column;
        align-items: stretch;
    }
    .explorer-filter-bar {
        flex-direction: column;
        align-items: stretch;
    }
    .explorer-search-input {
        width: 100%;
        min-width: unset;
    }
    .popular-conv-grid {
        grid-template-columns: 1fr;
    }
    .universal-units-grid {
        grid-template-columns: 1fr 1fr;
        max-height: 520px;
    }
}

@media (max-width: 480px) {
    .universal-units-grid {
        grid-template-columns: 1fr;
    }
}

/* Formula Box & Result Display for Primary G to CG Focus */
.formula-box {
    margin-top: 14px;
    background: rgba(108, 99, 255, 0.1);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 10px;
    padding: 12px 16px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    font-size: 14px;
}
.formula-box strong {
    color: var(--color-accent-2);
    font-family: var(--font-mono);
}
.formula-box span {
    color: var(--color-text-secondary);
}

.result-display-banner {
    margin-top: 14px;
    padding: 14px 18px;
    background: linear-gradient(135deg, rgba(0, 210, 255, 0.12), rgba(108, 99, 255, 0.12));
    border: 1px solid rgba(0, 210, 255, 0.35);
    border-radius: 12px;
    font-family: var(--font-mono);
    font-size: 1.25rem;
    font-weight: 800;
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
}
.result-display-banner .res-accent {
    color: var(--color-accent-2);
}

.quick-conv-strip {
    margin-top: 14px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}
.quick-conv-lbl {
    font-size: 12px;
    font-weight: 700;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.quick-conv-link {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--color-border-subtle);
    color: var(--color-accent-3);
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 12.5px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--trans-fast);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}
.quick-conv-link:hover {
    background: rgba(108, 99, 255, 0.2);
    border-color: var(--color-accent-1);
    color: #ffffff;
    transform: translateY(-1px);
}
.quick-conv-link.active {
    background: linear-gradient(135deg, rgba(108, 99, 255, 0.4), rgba(0, 210, 255, 0.4));
    border-color: var(--color-accent-2);
    color: #ffffff;
    box-shadow: 0 0 12px rgba(0, 210, 255, 0.35);
}
.quick-conv-link:active {
    transform: scale(0.96);
}

.reverse-calc-box {
    margin-top: 20px;
    padding: 20px;
    background: rgba(14, 14, 36, 0.7);
    border: 1px solid rgba(0, 210, 255, 0.25);
    border-radius: 14px;
}

/* Popular Conversions Grid */
.popular-conv-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
    gap: 12px;
    margin-top: 16px;
}

.popular-conv-btn {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--color-border-subtle);
    border-radius: 12px;
    padding: 12px 16px;
    color: var(--color-text-primary);
    font-family: var(--font-sans);
    font-size: 14px;
    cursor: pointer;
    transition: all var(--trans-fast);
    text-align: left;
    width: 100%;
}

.popular-conv-btn:hover, .popular-conv-btn:focus-visible {
    background: rgba(108, 99, 255, 0.15);
    border-color: var(--color-accent-2);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 210, 255, 0.15);
    outline: none;
}

.popular-conv-btn .pc-query {
    font-weight: 600;
    color: #ffffff;
}

.popular-conv-btn .pc-result {
    font-family: var(--font-mono);
    font-weight: 700;
    color: var(--color-accent-2);
}

/* Dynamic explanation sentence below result */
.result-explanation-text {
    margin-top: 8px;
    font-size: 13.5px;
    color: var(--color-text-secondary);
    line-height: 1.5;
    padding: 0 4px;
}

/* Compact Formula Box */
.compact-formula-box {
    margin-top: 16px;
    padding: 14px 18px;
    background: rgba(108, 99, 255, 0.08);
    border: 1px solid rgba(108, 99, 255, 0.3);
    border-radius: 12px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-around;
    gap: 12px;
    font-size: 14px;
    color: #ffffff;
}

.compact-formula-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-family: var(--font-mono);
    font-weight: 700;
}

.compact-formula-item .f-tag {
    color: var(--color-accent-2);
}

.compact-formula-divider {
    color: rgba(255, 255, 255, 0.2);
    font-weight: 300;
}

/* Metric Mass Ladder Flow */
.metric-flow-wrapper {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin: 20px 0;
    padding: 16px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--color-border-subtle);
    border-radius: 14px;
}

.metric-flow-node {
    padding: 10px 18px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 14px;
    font-weight: 600;
    color: #ffffff;
    text-align: center;
}

.metric-flow-node.highlight-g {
    border-color: var(--color-accent-1);
    background: rgba(108, 99, 255, 0.2);
    color: #ffffff;
}

.metric-flow-node.highlight-cg {
    border-color: var(--color-accent-2);
    background: rgba(0, 210, 255, 0.18);
    color: var(--color-accent-2);
}

.metric-flow-arrow {
    color: var(--color-text-tertiary);
    font-size: 16px;
    font-weight: 700;
}

/* ==========================================================================
   INTERACTIVE SECTIONS & DIAGRAMS DESIGN SYSTEM
   ========================================================================== */

/* 1. Interactive 100-Particle Grid */
.interactive-box {
    background: rgba(18, 18, 42, 0.75);
    border: 1px solid var(--color-bg-card-border);
    border-radius: 16px;
    padding: 24px;
    backdrop-filter: blur(16px);
    box-shadow: var(--shadow-card);
}
.interactive-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    margin-bottom: 16px;
}
.interactive-label {
    font-size: 14px;
    font-weight: 700;
    color: #ffffff;
}
.interactive-status-pill {
    font-family: var(--font-mono);
    font-size: 12px;
    background: rgba(0, 210, 255, 0.12);
    border: 1px solid rgba(0, 210, 255, 0.35);
    color: var(--color-accent-2);
    padding: 4px 12px;
    border-radius: 20px;
    font-weight: 600;
}
.particle-matrix-wrapper {
    background: rgba(7, 7, 20, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 16px;
}
.particle-matrix-grid {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 6px;
}
.cg-dot {
    aspect-ratio: 1;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.15);
    transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
    cursor: pointer;
}
.cg-dot.active {
    background: linear-gradient(135deg, #00d2ff, #6c63ff);
    border-color: #00d2ff;
    box-shadow: 0 0 10px rgba(0, 210, 255, 0.6);
    transform: scale(1.05);
}
.cg-dot:hover {
    transform: scale(1.35);
    z-index: 2;
    box-shadow: 0 0 14px #ffffff;
}
.fluid-controls {
    margin-top: 14px;
}
.fluid-slider-label {
    display: block;
    font-size: 13px;
    color: var(--color-text-secondary);
    margin-bottom: 8px;
}
.range-slider {
    width: 100%;
    height: 6px;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.12);
    outline: none;
    -webkit-appearance: none;
    accent-color: var(--color-accent-2);
}
.range-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--color-accent-2);
    box-shadow: 0 0 12px var(--color-accent-2);
    cursor: pointer;
    border: 2px solid #ffffff;
}
.interactive-caption {
    font-size: 13px;
    color: var(--color-text-tertiary);
    line-height: 1.5;
    margin-top: 12px;
}

/* 2. Mass Comparator Diagram */
.comparator-diagram {
    margin-top: 20px;
    background: rgba(18, 18, 42, 0.6);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 14px;
    padding: 18px 22px;
}
.comparator-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 14px;
}
.comparator-title {
    font-size: 13.5px;
    font-weight: 700;
    color: #ffffff;
    display: flex;
    align-items: center;
    gap: 8px;
}
.comparator-bars {
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.comparator-row {
    display: grid;
    grid-template-columns: 85px 1fr 110px;
    align-items: center;
    gap: 12px;
    font-size: 13px;
}
.comparator-track {
    height: 12px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 6px;
    overflow: hidden;
    position: relative;
}
.comparator-fill {
    height: 100%;
    border-radius: 6px;
    transition: width 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.comparator-fill.g-bar {
    background: linear-gradient(90deg, #6c63ff, #a78bfa);
}
.comparator-fill.cg-bar {
    background: linear-gradient(90deg, #00d2ff, #38ef7d);
    box-shadow: 0 0 10px rgba(0, 210, 255, 0.5);
}

/* 3. Interactive Decimal Shifter */
.decimal-shifter-box {
    margin-top: 24px;
    background: rgba(18, 18, 42, 0.7);
    border: 1px solid rgba(0, 210, 255, 0.25);
    border-radius: 14px;
    padding: 20px;
}
.shifter-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 12px;
}
.shifter-digits-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin: 20px 0;
    position: relative;
    padding-top: 30px;
    min-height: 90px;
}
.shifter-digit {
    width: 48px;
    height: 56px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: 26px;
    font-weight: 800;
    color: #ffffff;
}
.shifter-dot-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 22px;
}
.shifter-decimal-point {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--color-accent-2);
    box-shadow: 0 0 14px var(--color-accent-2);
}
.shifter-action-btn {
    background: linear-gradient(135deg, rgba(108, 99, 255, 0.3), rgba(0, 210, 255, 0.3));
    border: 1px solid var(--color-accent-2);
    color: #ffffff;
    padding: 8px 18px;
    border-radius: 8px;
    font-weight: 700;
    font-size: 13px;
    cursor: pointer;
    transition: all 0.2s ease;
}
.shifter-action-btn:hover {
    background: var(--color-accent-2);
    color: #070714;
    box-shadow: 0 0 16px var(--color-accent-2);
}

/* 4. Table Filter Bar & Clickable Rows */
.table-filter-bar {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 14px;
    margin-bottom: 16px;
}
.table-search-input {
    flex: 1;
    min-width: 220px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 10px;
    padding: 10px 16px;
    color: #ffffff;
    font-size: 13.5px;
    outline: none;
    transition: border-color var(--trans-fast);
}
.table-search-input:focus {
    border-color: var(--color-accent-2);
    box-shadow: 0 0 12px rgba(0, 210, 255, 0.25);
}
.table-chips {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}
.table-chip-btn {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--color-text-secondary);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}
.table-chip-btn.active, .table-chip-btn:hover {
    background: var(--color-accent-1);
    color: #ffffff;
    border-color: var(--color-accent-1);
}
.data-table tbody tr {
    cursor: pointer;
    transition: background 0.15s ease;
}
.data-table tbody tr:hover {
    background: rgba(108, 99, 255, 0.18);
}
.data-table tbody tr:hover td {
    color: var(--color-accent-2);
}

/* 5. Real-World Object Showcase */
.object-scale-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 16px;
    margin: 24px 0;
}
.object-scale-card {
    background: rgba(18, 18, 42, 0.7);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 14px;
    padding: 18px;
    text-align: center;
    cursor: pointer;
    transition: all var(--trans-smooth);
    position: relative;
    overflow: hidden;
}
.object-scale-card:hover, .object-scale-card.active {
    border-color: var(--color-accent-2);
    background: rgba(26, 26, 64, 0.85);
    transform: translateY(-4px);
    box-shadow: 0 12px 28px -8px rgba(0, 210, 255, 0.3);
}
.object-icon-circle {
    width: 52px;
    height: 52px;
    border-radius: 50%;
    margin: 0 auto 12px;
    background: rgba(255, 255, 255, 0.06);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    border: 1px solid rgba(255, 255, 255, 0.12);
}
.object-mass-tag {
    font-family: var(--font-mono);
    font-size: 15px;
    font-weight: 800;
    color: var(--color-accent-2);
    margin-bottom: 4px;
}
.object-title {
    font-size: 13.5px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 6px;
}
.object-desc {
    font-size: 12px;
    color: var(--color-text-secondary);
    line-height: 1.4;
}
.btn-object-test {
    margin-top: 10px;
    padding: 4px 10px;
    font-size: 11px;
    font-weight: 700;
    background: rgba(0, 210, 255, 0.1);
    border: 1px solid rgba(0, 210, 255, 0.3);
    color: var(--color-accent-2);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
}
.btn-object-test:hover {
    background: var(--color-accent-2);
    color: #070714;
}

/* 6. Metric Staircase Diagram */
.metric-staircase-container {
    margin: 24px 0;
    background: rgba(18, 18, 42, 0.7);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 16px;
    padding: 24px;
}
.staircase-visual {
    display: flex;
    align-items: flex-end;
    justify-content: center;
    gap: 8px;
    height: 180px;
    padding: 10px 0;
    border-bottom: 2px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 20px;
}
.stair-step {
    flex: 1;
    max-width: 90px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px 8px 0 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-end;
    padding-bottom: 10px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.stair-step:hover, .stair-step.active {
    background: linear-gradient(180deg, rgba(0, 210, 255, 0.4), rgba(108, 99, 255, 0.4));
    border-color: var(--color-accent-2);
    box-shadow: 0 0 16px rgba(0, 210, 255, 0.4);
    transform: translateY(-4px);
}
.stair-step.step-g {
    background: rgba(108, 99, 255, 0.25);
    border-color: var(--color-accent-1);
}
.stair-step.step-cg {
    background: rgba(0, 210, 255, 0.25);
    border-color: var(--color-accent-2);
}
.stair-symbol {
    font-size: 15px;
    font-weight: 800;
    color: #ffffff;
}
.stair-power {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--color-text-secondary);
    margin-top: 2px;
}
.stair-info-card {
    background: rgba(7, 7, 20, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 16px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
}
.stair-info-title {
    font-size: 15px;
    font-weight: 700;
    color: #ffffff;
}
.stair-info-val {
    font-family: var(--font-mono);
    font-size: 13.5px;
    color: var(--color-accent-2);
    font-weight: 700;
}

/* 7. Try in Calculator Button */
.btn-try-calc {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 10px;
    padding: 6px 14px;
    background: rgba(108, 99, 255, 0.15);
    border: 1px solid rgba(108, 99, 255, 0.35);
    border-radius: 16px;
    color: var(--color-accent-2);
    font-size: 12.5px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: all var(--trans-fast);
}
.btn-try-calc:hover {
    background: var(--color-accent-1);
    color: #ffffff;
    transform: translateX(3px);
}

/* ==========================================================================
   NEW INTERACTIVE DIAGRAMS & SECTIONS STYLING
   ========================================================================== */

/* Core Answer Panel (Above the Fold) */
.core-answer-panel {
    margin-top: 14px;
    padding: 12px 16px;
    background: rgba(108, 99, 255, 0.08);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 12px;
}
.core-answer-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 8px;
}
.core-math-badge {
    display: inline-flex;
    align-items: center;
    padding: 5px 12px;
    background: rgba(0, 210, 255, 0.1);
    border: 1px solid rgba(0, 210, 255, 0.3);
    border-radius: 8px;
    color: var(--color-accent-2);
    font-size: 13px;
    font-weight: 700;
    font-family: var(--font-mono);
}
.core-formula-highlight {
    font-size: 13.5px;
    color: var(--color-text-secondary);
}
.core-formula-highlight code {
    color: #ffffff;
    background: rgba(255, 255, 255, 0.08);
    padding: 2px 8px;
    border-radius: 6px;
    font-family: var(--font-mono);
    font-weight: 700;
}

/* Live Visual Scale Ratio Bar */
.scale-ratio-bar-container {
    width: 100%;
    box-sizing: border-box;
    margin-top: 16px;
    padding-top: 14px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}
.scale-ratio-labels {
    display: flex;
    justify-content: space-between;
    font-size: 12.5px;
    margin-bottom: 6px;
}
.scale-ratio-track {
    width: 100%;
    height: 7px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 4px;
    overflow: hidden;
    position: relative;
}
.scale-ratio-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--color-accent-2), var(--color-accent-1));
    border-radius: 4px;
    transition: width 0.3s ease;
}

/* 1. Dedicated Decimal Shift Engine Diagram (Under How to Convert) */
#calc-engine-diagram-box {
    margin-top: 0;
    background: rgba(18, 18, 44, 0.85);
    border: 1px solid rgba(0, 210, 255, 0.28);
    box-shadow: 0 16px 36px -10px rgba(0, 210, 255, 0.15);
}
.decimal-engine-body {
    display: flex;
    flex-direction: column;
    gap: 16px;
}
.engine-input-controls {
    background: rgba(7, 7, 22, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 14px;
}
.engine-ctrl-label {
    display: block;
    font-size: 13px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 8px;
}
.engine-ctrl-row {
    display: flex;
    align-items: center;
    gap: 12px;
}
.engine-chips-strip {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 10px;
}
.engine-chip {
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 600;
    font-family: var(--font-mono);
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--color-text-secondary);
    border-radius: 8px;
    cursor: pointer;
    transition: all var(--trans-fast);
}
.engine-chip:hover, .engine-chip.active {
    background: rgba(0, 210, 255, 0.2);
    border-color: var(--color-accent-2);
    color: #ffffff;
}

.engine-diagram-graphic {
    background: rgba(10, 10, 30, 0.8);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 14px;
    padding: 18px;
}
.engine-track-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 16px;
}
.engine-stage-card {
    flex: 1;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    padding: 12px;
    text-align: center;
    transition: all var(--trans-fast);
}
.stage-input {
    border-color: rgba(0, 210, 255, 0.35);
}
.stage-output {
    border-color: rgba(108, 99, 255, 0.4);
    background: rgba(108, 99, 255, 0.08);
}
.stage-tag {
    display: block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--color-text-secondary);
    margin-bottom: 4px;
}
.stage-val {
    font-family: var(--font-mono);
    font-size: 16px;
    font-weight: 800;
    color: #ffffff;
}
.stage-output .stage-val {
    color: var(--color-accent-2);
}

.engine-operator-node {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 0 4px;
}
.op-bubble {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-accent-1), var(--color-accent-2));
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: 12.5px;
    font-weight: 800;
    color: #ffffff;
    box-shadow: 0 0 16px rgba(0, 210, 255, 0.4);
}
.op-sub {
    font-size: 10px;
    color: var(--color-accent-3);
    margin-top: 4px;
    font-weight: 600;
    text-align: center;
}

.engine-digit-flow {
    background: rgba(0, 0, 0, 0.3);
    border: 1px dashed rgba(255, 255, 255, 0.12);
    border-radius: 10px;
    padding: 14px;
    text-align: center;
}
.flow-label {
    display: block;
    font-size: 12px;
    color: var(--color-text-secondary);
    margin-bottom: 10px;
}
.digit-cells-row {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    margin-bottom: 8px;
}
.digit-cell {
    min-width: 34px;
    height: 42px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: 18px;
    font-weight: 800;
    color: #ffffff;
    transition: all 0.25s ease;
}
.digit-cell.shifted {
    background: rgba(0, 210, 255, 0.2);
    border-color: var(--color-accent-2);
    color: var(--color-accent-2);
    transform: scale(1.05);
}
.digit-cell-dot {
    width: 14px;
    height: 42px;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding-bottom: 6px;
    font-size: 24px;
    font-weight: 900;
    color: var(--color-accent-2);
}
.digit-equation-text {
    font-family: var(--font-mono);
    font-size: 14px;
    font-weight: 700;
    color: var(--color-accent-2);
}
.engine-unit-cancel-box {
    margin-top: 12px;
    padding: 8px 12px;
    background: rgba(108, 99, 255, 0.1);
    border-radius: 8px;
    font-size: 12.5px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
}
.engine-unit-cancel-box code {
    color: #00D2FF;
    font-family: var(--font-mono);
    font-weight: 700;
}
.engine-footer-action {
    display: flex;
    justify-content: flex-end;
}

/* 2. Formula & Factor Simulator */
.formula-highlight-box {
    display: inline-block;
    padding: 10px 20px;
    background: rgba(0, 210, 255, 0.1);
    border: 1px solid rgba(0, 210, 255, 0.35);
    border-radius: 10px;
    color: #00D2FF;
    font-size: 1.25rem;
    font-family: var(--font-mono);
    margin: 8px 0 16px;
}
.formula-sim-body {
    display: flex;
    flex-direction: column;
    gap: 16px;
}
.sim-equation-visual {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    background: rgba(7, 7, 22, 0.7);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 16px;
}
.sim-block {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 10px;
    padding: 10px 8px;
    text-align: center;
}
.sim-block-lbl {
    font-size: 11px;
    font-weight: 700;
    color: var(--color-text-secondary);
    margin-bottom: 6px;
}
.sim-input-field {
    width: 100%;
    max-width: 90px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--color-accent-1);
    border-radius: 6px;
    color: #ffffff;
    font-family: var(--font-mono);
    font-size: 15px;
    font-weight: 700;
    text-align: center;
    padding: 4px;
}
.sim-factor-val {
    font-family: var(--font-mono);
    font-size: 16px;
    font-weight: 800;
    color: #A78BFA;
}
.sim-result-val {
    font-family: var(--font-mono);
    font-size: 16px;
    font-weight: 800;
    color: var(--color-accent-2);
}
.sim-op-symbol {
    font-size: 20px;
    font-weight: 800;
    color: var(--color-text-secondary);
}
.sim-factor-card {
    background: rgba(18, 18, 42, 0.6);
    border: 1px solid rgba(108, 99, 255, 0.2);
    border-radius: 10px;
    padding: 14px;
}
.sim-factor-title {
    font-size: 13.5px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 4px;
}
.sim-factor-desc {
    font-size: 12.5px;
    color: var(--color-text-secondary);
    line-height: 1.45;
    margin-bottom: 10px;
}
.sim-ratio-row {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}
.sim-pill {
    padding: 4px 10px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 6px;
    font-size: 11.5px;
    font-family: var(--font-mono);
    color: var(--color-accent-2);
}

/* 3. Conversion Table Visual Distribution Chart */
.table-dist-chart {
    background: rgba(7, 7, 22, 0.7);
    border: 1px solid rgba(108, 99, 255, 0.2);
    border-radius: 12px;
    padding: 14px 18px;
    margin-bottom: 16px;
}
.chart-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}
.chart-title {
    font-size: 13px;
    font-weight: 700;
    color: #ffffff;
}
.chart-active-tag {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 700;
    color: var(--color-accent-2);
}
.chart-bars-wrap {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.chart-bar-row {
    display: flex;
    align-items: center;
    gap: 12px;
}
.chart-bar-lbl {
    width: 120px;
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-secondary);
}
.chart-track {
    flex: 1;
    height: 10px;
    background: rgba(255, 255, 255, 0.06);
    border-radius: 6px;
    overflow: hidden;
}
.chart-fill {
    height: 100%;
    border-radius: 6px;
    transition: width 0.3s ease;
}
.fill-g {
    background: var(--color-accent-1);
}
.fill-cg {
    background: var(--color-accent-2);
}
.chart-val-txt {
    width: 80px;
    text-align: right;
    font-family: var(--font-mono);
    font-size: 12.5px;
    font-weight: 700;
    color: #ffffff;
}

.data-table tr.highlight-row {
    background: rgba(0, 210, 255, 0.12) !important;
}
.btn-table-load {
    padding: 4px 10px;
    font-size: 11.5px;
    font-weight: 700;
    background: rgba(108, 99, 255, 0.15);
    border: 1px solid rgba(108, 99, 255, 0.35);
    color: var(--color-accent-2);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
}
.btn-table-load:hover {
    background: var(--color-accent-2);
    color: #070714;
}

/* 4. Common Queries Cards Grid */
.common-queries-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 14px;
    margin: 20px 0;
}
.common-query-card {
    background: rgba(18, 18, 42, 0.65);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 16px;
    cursor: pointer;
    transition: all var(--trans-fast);
}
.common-query-card:hover, .common-query-card.active {
    border-color: var(--color-accent-2);
    background: rgba(24, 24, 56, 0.85);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px -6px rgba(0, 210, 255, 0.25);
}
.query-title {
    font-size: 13.5px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 6px;
}
.query-math {
    font-family: var(--font-mono);
    font-size: 12.5px;
    font-weight: 700;
    color: var(--color-accent-2);
    margin-bottom: 6px;
}
.query-answer {
    font-size: 12px;
    color: var(--color-text-secondary);
    margin-bottom: 10px;
    line-height: 1.4;
}
.btn-card-load {
    padding: 3px 8px;
    font-size: 11px;
    font-weight: 700;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 6px;
    color: var(--color-accent-2);
    cursor: pointer;
    transition: all var(--trans-fast);
}
.btn-card-load:hover {
    background: var(--color-accent-2);
    color: #070714;
}

/* 5. Solver Workpad */
.solver-workpad-body {
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.solver-input-row {
    display: flex;
    align-items: center;
    gap: 10px;
}
.solver-preset.active {
    background: var(--color-accent-2);
    color: #070714;
    border-color: var(--color-accent-2);
}
.solver-derivation-output {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.solver-step-card {
    background: rgba(7, 7, 22, 0.65);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 8px;
    padding: 10px 12px;
}
.solver-step-num {
    display: block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--color-accent-3);
    margin-bottom: 4px;
}
.solver-step-body {
    font-size: 12.5px;
    color: var(--color-text-secondary);
    line-height: 1.4;
}
.solver-math-code {
    display: block;
    margin-top: 4px;
    padding: 4px 8px;
    background: rgba(255, 255, 255, 0.04);
    border-radius: 6px;
    font-family: var(--font-mono);
    font-weight: 700;
    color: var(--color-accent-2);
}

/* 6. Metric Definitions Row & Links */
.metric-definitions-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}
.metric-def-col {
    background: rgba(18, 18, 42, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 18px;
}
.metric-def-col h3 {
    font-size: 1.15rem;
    color: #ffffff;
    margin-bottom: 8px;
}
.internal-link {
    color: var(--color-accent-2);
    font-weight: 600;
    text-decoration: underline;
    transition: color 0.2s ease;
}
.internal-link:hover {
    color: #ffffff;
}

/* 7. Scientific Notation Visualizer */
.scinote-body {
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.scinote-input-row {
    display: flex;
    align-items: center;
    gap: 10px;
}
.scinote-display-card {
    background: rgba(7, 7, 22, 0.7);
    border: 1px solid rgba(108, 99, 255, 0.25);
    border-radius: 10px;
    padding: 14px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.scinote-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
}
.scinote-lbl {
    color: var(--color-text-secondary);
}
.scinote-val {
    font-family: var(--font-mono);
    font-weight: 700;
    color: #ffffff;
}
.scinote-val-accent {
    font-family: var(--font-mono);
    font-size: 16px;
    font-weight: 800;
    color: var(--color-accent-2);
}
.scinote-slider-wrap {
    background: rgba(255, 255, 255, 0.03);
    border-radius: 8px;
    padding: 12px;
}
.sci-slider-scale {
    display: flex;
    justify-content: space-between;
    font-family: var(--font-mono);
    font-size: 10.5px;
    color: var(--color-text-tertiary);
    margin-top: 6px;
}

/* ==========================================================================
   SUPPORTING TOOLS SHOWCASE SECTION (ALL 17 CONVERTERS)
   ========================================================================== */
.tools-suite-section {
    margin: 50px 0 30px;
    position: relative;
}
.tools-filter-strip {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin: 20px 0 24px;
}
.tools-filter-btn {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--color-text-secondary);
    padding: 7px 14px;
    border-radius: 9999px;
    font-size: 12.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
}
.tools-filter-btn:hover {
    background: rgba(108, 99, 255, 0.12);
    border-color: rgba(108, 99, 255, 0.35);
    color: #ffffff;
}
.tools-filter-btn.active {
    background: linear-gradient(135deg, rgba(108, 99, 255, 0.3), rgba(0, 210, 255, 0.2));
    border-color: var(--color-accent-2);
    color: #ffffff;
    box-shadow: 0 0 12px rgba(0, 210, 255, 0.25);
}
.tools-showcase-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 16px;
}
.tool-showcase-card {
    background: rgba(18, 18, 42, 0.65);
    border: 1px solid rgba(108, 99, 255, 0.2);
    border-radius: 14px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    text-decoration: none;
    transition: all var(--trans-smooth);
    position: relative;
    overflow: hidden;
    backdrop-filter: blur(12px);
}
.tool-showcase-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--color-accent-1), var(--color-accent-2), transparent);
    opacity: 0;
    transition: opacity var(--trans-fast);
}
.tool-showcase-card:hover {
    transform: translateY(-4px);
    border-color: rgba(0, 210, 255, 0.45);
    background: rgba(26, 26, 60, 0.85);
    box-shadow: 0 12px 30px -8px rgba(0, 0, 0, 0.5), 0 0 20px rgba(108, 99, 255, 0.2);
}
.tool-showcase-card:hover::before {
    opacity: 1;
}
.tool-card-top {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 12px;
}
.tool-card-icon-wrap {
    width: 38px;
    height: 38px;
    border-radius: 10px;
    background: linear-gradient(135deg, rgba(108, 99, 255, 0.2), rgba(0, 210, 255, 0.15));
    border: 1px solid rgba(108, 99, 255, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}
.tool-pill-ratio {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 700;
    padding: 3px 8px;
    border-radius: 6px;
    background: rgba(0, 210, 255, 0.12);
    color: var(--color-accent-2);
    border: 1px solid rgba(0, 210, 255, 0.25);
}
.tool-card-title {
    font-size: 16px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 6px;
    line-height: 1.35;
}
.tool-card-desc {
    font-size: 12.5px;
    color: var(--color-text-secondary);
    line-height: 1.5;
    margin-bottom: 14px;
}
.tool-card-formula {
    background: rgba(7, 7, 22, 0.6);
    border: 1px dashed rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    padding: 6px 10px;
    font-family: var(--font-mono);
    font-size: 11.5px;
    color: #a78bfa;
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 14px;
}
.tool-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 10px;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.tool-status-tag {
    font-size: 10.5px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: #10b981;
    display: flex;
    align-items: center;
    gap: 5px;
}
.tool-status-tag::before {
    content: '';
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: #10b981;
    box-shadow: 0 0 8px #10b981;
}
.tool-cta-text {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-accent-2);
    display: flex;
    align-items: center;
    gap: 4px;
    transition: transform var(--trans-fast);
}
.tool-showcase-card:hover .tool-cta-text {
    transform: translateX(3px);
}

.current-tool-card { border-color: var(--color-accent-2) !important; background: linear-gradient(135deg, rgba(0, 210, 255, 0.08), rgba(108, 99, 255, 0.12)) !important; box-shadow: 0 0 20px rgba(0, 210, 255, 0.25) !important; }




/* COMPACT HERO (Above-the-Fold Optimization) */
.hero.hero-compact {
    text-align: center;
    padding: 20px 0 12px;
}

.hero.hero-compact h1 {
    font-size: 36px;
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin-bottom: 0;
}

/* POST-TOOL OVERVIEW SECTION (Description & Presets moved after tool) */
.hero-overview-section {
    margin-top: 24px;
    padding-top: 0;
    text-align: center;
}

.hero-overview-section .hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(108, 99, 255, 0.12);
    border: 1px solid rgba(108, 99, 255, 0.3);
    padding: 6px 16px;
    border-radius: 30px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--color-accent-2);
    margin-bottom: 14px;
}

.hero-overview-section .hero-desc {
    color: var(--color-text-secondary);
    max-width: 760px;
    margin: 0 auto 20px;
    font-size: 16px;
    line-height: 1.65;
}

.hero-overview-section .preset-strip {
    margin-top: 10px;
}

/* MOBILE OPTIMIZATION & ABOVE-THE-FOLD GUARANTEE */
@media (max-width: 768px) {
    html, body {
        overflow-x: hidden !important;
        max-width: 100vw !important;
        width: 100% !important;
    }
    .site-container {
        padding: 0 16px !important;
        width: 100% !important;
        max-width: 100% !important;
        box-sizing: border-box !important;
    }
    .site-header {
        padding: 0 16px;
    }
    .header-inner {
        height: 60px;
        padding: 0;
    }
    .mobile-nav {
        top: 60px;
        padding: 16px 12px 32px;
    }
    .hero.hero-compact {
        padding: 12px 0 8px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .hero.hero-compact h1 {
        font-size: 21px;
        line-height: 1.3;
        margin-bottom: 0;
        word-break: break-word;
        overflow-wrap: break-word;
        padding: 0 4px;
    }
    .calc-card {
        margin-top: 6px;
        margin-bottom: 24px;
        padding: 16px 12px;
        border-radius: 16px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
        overflow: hidden;
    }
    .calc-header-row {
        gap: 10px;
        margin-bottom: 12px;
        padding-bottom: 10px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
        display: flex;
        flex-direction: column;
    }
    .calc-title {
        font-size: 16px;
        line-height: 1.3;
        word-break: break-word;
    }
    .calc-subtitle {
        display: none;
    }
    .calc-type-switch {
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
        display: flex;
        gap: 4px;
        padding: 4px;
        background: rgba(0, 0, 0, 0.45);
        border-radius: 12px;
    }
    .radio-tab {
        flex: 1 1 0;
        min-width: 0;
        justify-content: center;
        align-items: center;
        padding: 8px 4px;
        font-size: 11px;
        line-height: 1.25;
        white-space: normal;
        text-align: center;
        border-radius: 8px;
    }
    .radio-tab .radio-label {
        display: block;
        word-break: break-word;
    }
    .calc-layout-grid {
        display: flex;
        flex-direction: column;
        gap: 16px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .calc-controls-col {
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .calc-field {
        margin-bottom: 8px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .field-header {
        width: 100%;
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
    .calc-input-row {
        display: flex;
        align-items: center;
        gap: 6px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .calc-input {
        flex: 1 1 0 !important;
        min-width: 0 !important;
        width: 0 !important;
        height: 44px;
        font-size: 16px; /* Prevents auto zoom-in on iPhone Safari */
        padding: 0 10px;
        border-radius: 10px;
        box-sizing: border-box;
    }
    .calc-result-input {
        font-size: 18px !important;
        letter-spacing: 0 !important;
    }
    .unit-tag {
        flex-shrink: 0;
        height: 44px;
        padding: 0 10px !important;
        font-size: 13px !important;
        display: inline-flex;
        align-items: center;
        justify-content: center;
        border-radius: 10px;
        box-sizing: border-box;
    }
    .calc-select,
    .calc-result-select {
        width: 80px;
        height: 44px;
        font-size: 13px;
        padding: 0 6px;
        border-radius: 10px;
        flex-shrink: 0;
    }
    .btn-copy {
        flex-shrink: 0;
        width: 44px;
        height: 44px;
        min-width: 44px;
        padding: 0;
        display: inline-flex;
        align-items: center;
        justify-content: center;
        border-radius: 10px;
        box-sizing: border-box;
    }
    .conversion-indicator-row {
        margin: 6px 0;
        width: 100%;
    }
    .conv-swap-btn {
        padding: 5px 12px;
        font-size: 11.5px;
        white-space: nowrap;
    }
    .calc-action-btns-group {
        margin-top: 12px !important;
        display: flex;
        gap: 8px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .btn-calc-convert {
        flex: 1 1 0;
        min-width: 0;
        justify-content: center;
        padding: 10px 10px;
        font-size: 13px;
        min-height: 44px;
        white-space: nowrap;
        border-radius: 10px;
    }
    .btn-calc-clear {
        flex-shrink: 0;
        justify-content: center;
        padding: 10px 14px;
        font-size: 13px;
        min-height: 44px;
        border-radius: 10px;
    }
    .result-display-banner {
        padding: 10px 12px;
        font-size: 14.5px;
        margin-top: 10px;
        word-break: break-word;
        overflow-wrap: break-word;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .result-explanation-text {
        font-size: 12.5px;
        margin-top: 6px;
        line-height: 1.4;
        word-break: break-word;
    }
    .core-answer-panel {
        padding: 10px;
        margin-top: 8px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .core-answer-row {
        display: flex;
        flex-direction: column;
        gap: 6px;
        width: 100%;
    }
    .core-math-badge {
        font-size: 11.5px;
        padding: 6px 8px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
        text-align: center;
        justify-content: center;
        word-break: break-word;
        white-space: normal;
    }
    .core-formula-highlight {
        font-size: 12.5px;
        text-align: center;
        word-break: break-word;
    }
    .quick-conv-strip {
        gap: 6px;
        margin-top: 10px;
        display: flex;
        flex-wrap: wrap;
        align-items: center;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .quick-conv-lbl {
        font-size: 11px;
        font-weight: 700;
        color: var(--color-text-tertiary);
        width: 100%;
        margin-bottom: 2px;
    }
    .quick-conv-link {
        font-size: 11px;
        padding: 5px 8px;
        border-radius: 14px;
        min-height: 30px;
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }
    .calc-visual-col {
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    .live-diagram-card {
        padding: 14px 10px;
        border-radius: 16px;
        margin-top: 12px;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
        overflow: hidden;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    .diagram-tag {
        font-size: 9.5px;
        letter-spacing: 0.03em;
        text-transform: uppercase;
        padding: 4px 8px;
        text-align: center;
        white-space: normal;
        word-break: break-word;
        max-width: 100%;
        line-height: 1.3;
        display: inline-block;
        box-sizing: border-box;
    }
    .calc-diagram {
        width: 100%;
        max-width: 100%;
        display: flex;
        justify-content: center;
        overflow: hidden;
    }
    .main-calc-svg {
        width: 100%;
        max-width: 280px;
        height: auto;
        display: block;
    }
    .calc-formula {
        font-size: 12.5px;
        padding: 6px 10px;
        text-align: center;
        width: 100%;
        box-sizing: border-box;
        word-break: break-word;
    }
    .scale-ratio-labels {
        font-size: 10.5px;
    }
    .interactive-diagram-hint {
        font-size: 10.5px;
        text-align: center;
    }
}

/* Extra-Narrow Mobile Screens (< 480px & < 360px) */
@media (max-width: 480px) {
    .site-container {
        padding: 0 12px !important;
    }
    .calc-card {
        padding: 14px 10px;
    }
    .hero.hero-compact h1 {
        font-size: 19px;
    }
    .btn-calc-convert {
        font-size: 12.5px;
        padding: 9px 8px;
    }
    .btn-calc-clear {
        padding: 9px 12px;
        font-size: 12.5px;
    }
    .calc-result-input {
        font-size: 17px !important;
    }
}

@media (max-width: 360px) {
    .site-container {
        padding: 0 8px !important;
    }
    .calc-card {
        padding: 12px 8px;
    }
    .hero.hero-compact h1 {
        font-size: 17px;
    }
    .calc-type-switch {
        flex-direction: column;
        gap: 6px;
    }
    .radio-tab {
        padding: 7px 8px;
        font-size: 11px;
    }
    .unit-tag {
        padding: 0 6px !important;
        font-size: 12px !important;
    }
    .btn-copy {
        width: 40px;
        height: 40px;
        min-width: 40px;
    }
    .btn-calc-convert {
        font-size: 12px;
        padding: 8px 6px;
    }
    .btn-calc-clear {
        padding: 8px 10px;
        font-size: 12px;
    }
}

/* ==========================================================================
   LIGHT THEME COMPREHENSIVE OVERRIDES
   Rich, high-contrast, clean modern aesthetic for [data-theme="light"]
   ========================================================================== */
[data-theme="light"] body {
    background-color: var(--color-bg-body);
    color: var(--color-text-primary);
}

[data-theme="light"] .site-header {
    background: rgba(255, 255, 255, 0.88);
    border-bottom: 1px solid rgba(15, 23, 42, 0.08);
    box-shadow: 0 4px 20px rgba(15, 23, 42, 0.04);
}

[data-theme="light"] .header-brand {
    color: #0f172a;
}

[data-theme="light"] .nav-link {
    color: var(--color-text-secondary);
}
[data-theme="light"] .nav-link:hover,
[data-theme="light"] .nav-link.active {
    color: #0f172a;
    background: rgba(15, 23, 42, 0.06);
}

[data-theme="light"] .nav-dropdown-btn {
    color: var(--color-text-secondary);
}
[data-theme="light"] .nav-dropdown-btn:hover,
[data-theme="light"] .nav-dropdown-item:hover .nav-dropdown-btn,
[data-theme="light"] .nav-dropdown-item:focus-within .nav-dropdown-btn {
    color: #0f172a;
    background: rgba(15, 23, 42, 0.06);
}

[data-theme="light"] .nav-dropdown-menu {
    background: rgba(255, 255, 255, 0.98);
    border: 1px solid rgba(79, 70, 229, 0.2);
    box-shadow: 0 20px 50px rgba(15, 23, 42, 0.12), 0 0 25px rgba(79, 70, 229, 0.08);
}
[data-theme="light"] .dropdown-heading {
    color: #475569;
}
[data-theme="light"] .dropdown-link {
    color: #334155;
}
[data-theme="light"] .dropdown-link:hover {
    background: rgba(79, 70, 229, 0.08);
    color: #0f172a;
}
[data-theme="light"] .ratio-pill {
    background: rgba(2, 132, 199, 0.08);
    color: #0284c7;
    border: 1px solid rgba(2, 132, 199, 0.2);
}
[data-theme="light"] .dropdown-footer {
    border-top: 1px solid rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .dropdown-view-all {
    color: #4f46e5;
}

[data-theme="light"] .btn-theme-toggle {
    background: rgba(15, 23, 42, 0.05);
    border: 1px solid rgba(15, 23, 42, 0.12);
    color: #4f46e5;
}
[data-theme="light"] .btn-theme-toggle:hover {
    background: rgba(79, 70, 229, 0.1);
    border-color: #4f46e5;
    color: #4338ca;
}

[data-theme="light"] .btn-header-secondary {
    background: rgba(15, 23, 42, 0.04);
    border: 1px solid rgba(15, 23, 42, 0.12);
    color: #0f172a;
}
[data-theme="light"] .btn-header-secondary:hover {
    background: rgba(15, 23, 42, 0.08);
    border-color: rgba(15, 23, 42, 0.2);
}
[data-theme="light"] .mobile-toggle {
    color: #0f172a;
}
[data-theme="light"] .mobile-nav {
    background: rgba(255, 255, 255, 0.98);
    border-top: 1px solid rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .mob-link {
    color: #0f172a;
    background: rgba(15, 23, 42, 0.02);
    border-color: rgba(15, 23, 42, 0.06);
}
[data-theme="light"] .mob-link:hover,
[data-theme="light"] .mob-link:active {
    background: rgba(79, 70, 229, 0.08);
    border-color: rgba(79, 70, 229, 0.2);
}
[data-theme="light"] .mob-tools-dropdown {
    background: rgba(15, 23, 42, 0.02);
    border-color: rgba(79, 70, 229, 0.2);
}
[data-theme="light"] .mob-tools-btn {
    color: #0f172a;
    background: rgba(15, 23, 42, 0.03);
}
[data-theme="light"] .mob-tools-panel {
    background: rgba(241, 245, 249, 0.85);
    border-top-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .mob-tool-row {
    color: #334155;
    background: #ffffff;
    border: 1px solid rgba(15, 23, 42, 0.06);
}
[data-theme="light"] .mob-tool-row:hover {
    background: rgba(79, 70, 229, 0.08);
    color: #0f172a;
}

[data-theme="light"] .orb {
    opacity: 0.07;
}
[data-theme="light"] .grid-overlay {
    opacity: 0.02;
}

[data-theme="light"] .calc-card,
[data-theme="light"] .glass-card {
    background: #ffffff;
    border: 1px solid rgba(15, 23, 42, 0.09);
    box-shadow: 0 4px 24px -2px rgba(15, 23, 42, 0.07), 0 1px 3px rgba(15, 23, 42, 0.04);
}

[data-theme="light"] .calc-title,
[data-theme="light"] .section-title,
[data-theme="light"] .page-title {
    color: #0f172a;
}

[data-theme="light"] .calc-type-switch {
    background: #e2e8f0;
    border-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .radio-tab {
    color: #475569;
}
[data-theme="light"] .radio-tab:hover {
    color: #0f172a;
}
[data-theme="light"] .radio-tab.active {
    background: #4f46e5;
    color: #ffffff;
    box-shadow: 0 4px 14px rgba(79, 70, 229, 0.3);
}

[data-theme="light"] .calc-input {
    background: #f8fafc;
    border-color: #cbd5e1;
    color: #0f172a;
}
[data-theme="light"] .calc-input:focus {
    background: #ffffff;
    border-color: #4f46e5;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}
[data-theme="light"] .calc-select {
    background: #ffffff;
    border-color: #cbd5e1;
    color: #0284c7;
}
[data-theme="light"] .calc-select option {
    background: #ffffff;
    color: #0f172a;
}

[data-theme="light"] .conv-line {
    background: rgba(15, 23, 42, 0.1);
}
[data-theme="light"] .conv-swap-btn {
    background: #ffffff;
    border-color: #4f46e5;
    color: #4f46e5;
    box-shadow: 0 2px 8px rgba(79, 70, 229, 0.15);
}
[data-theme="light"] .conv-swap-btn:hover {
    background: #4f46e5;
    color: #ffffff;
}

[data-theme="light"] .calc-result-input {
    background: #f0fdf4 !important;
    border-color: #0284c7 !important;
    color: #0369a1 !important;
    box-shadow: 0 0 12px rgba(2, 132, 199, 0.2);
}
[data-theme="light"] .btn-copy {
    background: #f1f5f9;
    border-color: #cbd5e1;
    color: #334155;
}
[data-theme="light"] .btn-copy:hover {
    background: #e0f2fe;
    color: #0369a1;
    border-color: #0284c7;
}

[data-theme="light"] .conversions-strip {
    border-top-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .conv-item {
    background: #f1f5f9;
}
[data-theme="light"] .conv-val {
    color: #0f172a;
}

[data-theme="light"] .btn-reset {
    background: #f1f5f9;
    border-color: #cbd5e1;
    color: #475569;
}
[data-theme="light"] .btn-reset:hover {
    background: #e2e8f0;
    color: #0f172a;
}

[data-theme="light"] .btn-calc-clear {
    background: #f1f5f9;
    border-color: #cbd5e1;
    color: #475569;
}
[data-theme="light"] .btn-calc-clear:hover {
    background: #e2e8f0;
    color: #0f172a;
}

[data-theme="light"] .preset-pill {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.12);
    color: #334155;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}
[data-theme="light"] .preset-pill:hover {
    background: rgba(79, 70, 229, 0.08);
    border-color: #4f46e5;
    color: #4f46e5;
}

[data-theme="light"] .hero-badge,
[data-theme="light"] .hero-overview-section .hero-badge {
    background: rgba(79, 70, 229, 0.08);
    border-color: rgba(79, 70, 229, 0.25);
    color: #4f46e5;
}

[data-theme="light"] .quick-conv-link {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.12);
    color: #0284c7;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}
[data-theme="light"] .quick-conv-link:hover {
    background: rgba(2, 132, 199, 0.08);
    border-color: #0284c7;
    color: #0369a1;
}

[data-theme="light"] .field-hint {
    color: #64748b;
}

[data-theme="light"] .result-display-banner {
    background: linear-gradient(135deg, rgba(2, 132, 199, 0.08), rgba(79, 70, 229, 0.08));
    border-color: rgba(2, 132, 199, 0.3);
    color: #0f172a;
}
[data-theme="light"] .result-display-banner .res-accent {
    color: #0284c7;
}

[data-theme="light"] .core-answer-panel {
    background: rgba(79, 70, 229, 0.06);
    border-color: rgba(79, 70, 229, 0.2);
}
[data-theme="light"] .core-math-badge {
    background: #ffffff;
    border-color: rgba(2, 132, 199, 0.3);
    color: #0284c7;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}
[data-theme="light"] .core-formula-highlight code {
    color: #4f46e5;
    background: rgba(79, 70, 229, 0.1);
}

[data-theme="light"] .scale-ratio-track {
    background: #e2e8f0;
}
[data-theme="light"] .scale-ratio-bar-container {
    border-top-color: rgba(15, 23, 42, 0.08);
}

[data-theme="light"] .live-diagram-card {
    background: #ffffff;
    border-color: rgba(79, 70, 229, 0.2);
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.05);
}
[data-theme="light"] .diagram-tag {
    background: rgba(2, 132, 199, 0.1);
    color: #0284c7;
}
[data-theme="light"] .calc-formula {
    background: rgba(79, 70, 229, 0.08);
    border-color: rgba(79, 70, 229, 0.2);
    color: #4f46e5;
}
[data-theme="light"] .main-calc-svg rect[fill="rgba(10,10,26,0.92)"] {
    fill: #f1f5f9;
    stroke: rgba(79, 70, 229, 0.3);
}
[data-theme="light"] .main-calc-svg rect[fill="rgba(255,255,255,0.14)"] {
    fill: #cbd5e1;
}
[data-theme="light"] .main-calc-svg line[stroke="rgba(255,255,255,0.45)"] {
    stroke: #94a3b8;
}

[data-theme="light"] .interactive-box,
[data-theme="light"] .formula-sim-box,
[data-theme="light"] #calc-engine-diagram-box,
[data-theme="light"] #formula-sim-diagram-box,
[data-theme="light"] .solver-workpad-box,
[data-theme="light"] .scinote-box {
    background: #ffffff;
    border: 1px solid rgba(15, 23, 42, 0.08);
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.05);
}

[data-theme="light"] .engine-input-controls {
    background: #f8fafc;
    border-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .engine-ctrl-label {
    color: #0f172a;
}
[data-theme="light"] .engine-chip {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.12);
    color: #475569;
}
[data-theme="light"] .engine-chip:hover,
[data-theme="light"] .engine-chip.active {
    background: rgba(2, 132, 199, 0.12);
    border-color: #0284c7;
    color: #0284c7;
}
[data-theme="light"] .engine-diagram-graphic {
    background: #f8fafc;
    border-color: rgba(79, 70, 229, 0.2);
}
[data-theme="light"] .engine-stage-card {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.1);
}
[data-theme="light"] .stage-val {
    color: #0f172a;
}
[data-theme="light"] .engine-digit-flow {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.15);
}
[data-theme="light"] .digit-cell {
    background: #f1f5f9;
    border-color: #cbd5e1;
    color: #0f172a;
}
[data-theme="light"] .engine-unit-cancel-box {
    background: rgba(79, 70, 229, 0.08);
}
[data-theme="light"] .engine-unit-cancel-box code {
    color: #0284c7;
}

[data-theme="light"] .sim-equation-visual {
    background: #f8fafc;
    border-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .sim-block {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.1);
}
[data-theme="light"] .sim-input-field {
    background: #ffffff;
    border-color: #4f46e5;
    color: #0f172a;
}
[data-theme="light"] .sim-factor-card {
    background: #f8fafc;
    border-color: rgba(79, 70, 229, 0.15);
}
[data-theme="light"] .sim-factor-title {
    color: #0f172a;
}
[data-theme="light"] .sim-pill {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.12);
    color: #0284c7;
}

[data-theme="light"] .table-dist-chart {
    background: #f8fafc;
    border-color: rgba(79, 70, 229, 0.15);
}
[data-theme="light"] .chart-title {
    color: #0f172a;
}
[data-theme="light"] .chart-val-txt {
    color: #0f172a;
}
[data-theme="light"] .chart-track {
    background: #e2e8f0;
}

[data-theme="light"] .data-table th {
    color: #475569;
    border-bottom-color: rgba(15, 23, 42, 0.1);
}
[data-theme="light"] .data-table td {
    color: #1e293b;
    border-bottom-color: rgba(15, 23, 42, 0.06);
}
[data-theme="light"] .data-table tr:hover td {
    background: rgba(15, 23, 42, 0.03);
}
[data-theme="light"] .data-table tr.highlight-row td {
    background: rgba(2, 132, 199, 0.08) !important;
}

[data-theme="light"] .common-query-card {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.08);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
}
[data-theme="light"] .common-query-card:hover,
[data-theme="light"] .common-query-card.active {
    background: #ffffff;
    border-color: #0284c7;
    box-shadow: 0 8px 24px rgba(2, 132, 199, 0.15);
}
[data-theme="light"] .query-title {
    color: #0f172a;
}
[data-theme="light"] .btn-card-load {
    background: #f1f5f9;
    border-color: rgba(15, 23, 42, 0.12);
}

[data-theme="light"] .solver-step-card {
    background: #f8fafc;
    border-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .solver-step-num {
    color: #7c3aed;
}
[data-theme="light"] .solver-math-code {
    background: #ffffff;
    border: 1px solid rgba(15, 23, 42, 0.08);
    color: #0284c7;
}

[data-theme="light"] .metric-def-col {
    background: #ffffff;
    border-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .metric-def-col h3 {
    color: #0f172a;
}
[data-theme="light"] .internal-link:hover {
    color: #0f172a;
}

[data-theme="light"] .scinote-display-card {
    background: #f8fafc;
    border-color: rgba(79, 70, 229, 0.2);
}
[data-theme="light"] .scinote-val {
    color: #0f172a;
}
[data-theme="light"] .scinote-slider-wrap {
    background: #f1f5f9;
}

[data-theme="light"] .faq-item summary {
    color: #0f172a;
}
[data-theme="light"] .faq-item summary:hover {
    background: rgba(15, 23, 42, 0.03);
}

[data-theme="light"] .tools-filter-btn {
    background: #f1f5f9;
    border-color: rgba(15, 23, 42, 0.1);
    color: #475569;
}
[data-theme="light"] .tools-filter-btn:hover {
    background: rgba(79, 70, 229, 0.08);
    border-color: rgba(79, 70, 229, 0.3);
    color: #0f172a;
}
[data-theme="light"] .tools-filter-btn.active {
    background: #4f46e5;
    border-color: #4f46e5;
    color: #ffffff;
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.25);
}

[data-theme="light"] .tool-showcase-card {
    background: #ffffff;
    border: 1px solid rgba(15, 23, 42, 0.08);
    box-shadow: 0 4px 18px rgba(15, 23, 42, 0.05);
}
[data-theme="light"] .tool-showcase-card:hover {
    background: #ffffff;
    border-color: #4f46e5;
    box-shadow: 0 12px 28px rgba(79, 70, 229, 0.12);
}
[data-theme="light"] .tool-card-title {
    color: #0f172a;
}
[data-theme="light"] .tool-card-formula {
    background: #f8fafc;
    border-color: rgba(15, 23, 42, 0.12);
    color: #6d28d9;
}
[data-theme="light"] .tool-card-footer {
    border-top-color: rgba(15, 23, 42, 0.06);
}
[data-theme="light"] .tool-card-icon-wrap {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.12), rgba(2, 132, 199, 0.1));
    border-color: rgba(79, 70, 229, 0.2);
}
[data-theme="light"] .current-tool-card {
    border-color: #0284c7 !important;
    background: linear-gradient(135deg, rgba(2, 132, 199, 0.05), rgba(79, 70, 229, 0.08)) !important;
    box-shadow: 0 0 20px rgba(2, 132, 199, 0.15) !important;
}

[data-theme="light"] .site-footer {
    background: #f8fafc;
    border-top: 1px solid rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .footer-brand {
    color: #0f172a;
}
[data-theme="light"] .footer-heading {
    color: #0f172a;
}
[data-theme="light"] .footer-social-link {
    background: rgba(15, 23, 42, 0.04);
    border-color: rgba(15, 23, 42, 0.1);
    color: #475569;
}
[data-theme="light"] .footer-social-link:hover {
    background: rgba(79, 70, 229, 0.12);
    border-color: #4f46e5;
    color: #4f46e5;
}
[data-theme="light"] .lang-btn {
    background: rgba(15, 23, 42, 0.04);
    border-color: rgba(15, 23, 42, 0.1);
    color: #475569;
}
[data-theme="light"] .lang-btn:hover,
[data-theme="light"] .lang-btn.active {
    background: #4f46e5;
    border-color: #4f46e5;
    color: #ffffff;
}
[data-theme="light"] .footer-copy {
    color: #64748b;
    border-top-color: rgba(15, 23, 42, 0.08);
}

[data-theme="light"] .back-to-top {
    background: rgba(255, 255, 255, 0.95);
    border-color: #4f46e5;
    color: #4f46e5;
    box-shadow: 0 4px 20px rgba(15, 23, 42, 0.15);
}
[data-theme="light"] .back-to-top:hover {
    background: #4f46e5;
    color: #ffffff;
}

[data-theme="light"] .contact-form input,
[data-theme="light"] .contact-form textarea {
    background: #ffffff;
    border-color: #cbd5e1;
    color: #0f172a;
}
[data-theme="light"] .contact-form input:focus,
[data-theme="light"] .contact-form textarea:focus {
    border-color: #4f46e5;
    background: #ffffff;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

[data-theme="light"] .article-prose strong {
    color: #0f172a;
}
[data-theme="light"] .article-prose code {
    color: #4f46e5;
    background: rgba(79, 70, 229, 0.1);
}
[data-theme="light"] .article-prose hr {
    border-top-color: rgba(15, 23, 42, 0.08);
}
[data-theme="light"] .article-prose th {
    color: #475569;
    border-bottom-color: rgba(15, 23, 42, 0.12);
}
[data-theme="light"] .article-prose td {
    border-bottom-color: rgba(15, 23, 42, 0.06);
}

@media (max-width: 768px) {
    .btn-header-secondary { display: none; }
    .btn-header-primary { padding: 6px 12px; font-size: 12px; }
    .btn-theme-toggle { width: 36px; height: 36px; }
}