/* ==========================================================================
   SJMaths — Premium, Pixel-Perfect UI/UX Styles for Class 9 Advanced Science
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800;900&family=Poppins:wght@300;400;500;600;700;800&family=Fira+Code:wght@400;600&display=swap');

:root {
    /* Color Palette */
    --sj-p: #0f766e;        /* Deep Teal primary */
    --sj-pd: #0d9488;       /* Bright Teal secondary */
    --sj-a: #f59e0b;        /* Amber accent */
    --sj-bg: #f8fafc;       /* Soft page background */
    --sj-s: #0f172a;        /* Deep slate text */
    --sj-accent: #8b5cf6;   /* Purple/accent color */
    --sj-card-bg: #ffffff;  /* White card background */
    --sj-border: #e2e8f0;   /* Light border line */
    --sj-tab-bg: #f0fdfa;   /* Mint Tint background */
    --sj-tab-active: #0f766e;
    --sj-tab-text: #475569;
    --sj-radius: 24px;
    --sj-shadow: 0 10px 30px rgba(0, 0, 0, 0.04);

    /* Original Science variables for backward compatibility */
    --science-primary: #0f766e;
    --science-primary-hover: #0d9488;
    --science-primary-light: #f0fdfa;
    --science-secondary: #8b5cf6;
    --science-secondary-light: #f5f3ff;
    --science-dark: #0f172a;
    --science-muted: #64748b;
    --science-border: #e2e8f0;
    --science-soft: #f8fafc;
    --science-accent: #f59e0b;
    
    --font-outfit: 'Outfit', sans-serif;
    --font-poppins: 'Poppins', sans-serif;
}

/* ===== Base resets & typography overrides ===== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-poppins);
    background-color: var(--sj-bg);
    color: #334155;                 /* Slate 700 for premium readability */
    line-height: 1.8;               /* Generous reading comfort height */
    font-size: 1rem;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

p {
    margin-bottom: 1.5rem;
    color: #475569;                 /* Soft contrast slate */
    font-size: 0.98rem;
}

strong, b {
    color: var(--sj-s);
    font-weight: 700;
}

/* Elegant marker color for list items matching theme */
ul, ol {
    margin-bottom: 1.5rem;
    padding-left: 1.75rem;
}

li {
    margin-bottom: 0.6rem;
    line-height: 1.75;
    color: #475569;
}

li::marker {
    color: var(--sj-p);
    font-weight: 800;
}

/* Monospace font styling for scientific symbols and formula variables */
code, var, kbd, samp {
    font-family: 'Fira Code', 'Courier New', monospace;
    font-size: 0.9rem;
    background: #f1f5f9;
    padding: 3px 6px;
    border-radius: 6px;
    color: #0f172a;
}

/* Highlight helpers for key terms */
.highlight-term {
    color: var(--sj-p);
    font-weight: 600;
    border-bottom: 1.5px solid var(--sj-tab-bg);
    padding-bottom: 1px;
}

.sj-container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 24px 20px 80px;
}

/* ===== Premium Breadcrumbs & Top Navigation Bar ===== */
.sj-tbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 20px;
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(226, 232, 240, 0.8);
    border-radius: 16px;
    margin-bottom: 30px;
    box-shadow: 0 4px 20px rgba(15, 23, 42, 0.02);
}

.sj-bcrumb {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    font-size: 0.75rem;
    color: var(--science-muted);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-family: var(--font-outfit);
}

.sj-bcrumb a {
    color: inherit;
    text-decoration: none;
    transition: color 0.25s ease;
}

.sj-bcrumb a:hover {
    color: var(--sj-p);
}

.sj-bcrumb i {
    font-size: 0.65rem;
    color: #cbd5e1;
}

.sj-nav {
    display: flex;
    gap: 10px;
}

.sj-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 18px;
    border-radius: 50px;
    font-weight: 700;
    font-size: 0.78rem;
    text-decoration: none;
    background: #fff;
    color: var(--sj-p);
    border: 1.5px solid var(--sj-p);
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    min-height: 40px;
    font-family: var(--font-outfit);
    cursor: pointer;
}

.sj-btn:hover {
    background: var(--sj-tab-bg);
    border-color: var(--sj-pd);
    color: var(--sj-pd);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(15, 118, 110, 0.08);
}

/* ===== Science Hero Header Banner (Gradient Mesh Design) ===== */
.science-hero, .hero, .sj-hero-v6 {
    background: linear-gradient(135deg, #042f2e 0%, #0f766e 60%, #115e59 100%) !important;
    border-radius: 24px !important;
    padding: 50px 40px !important;
    color: #fff !important;
    text-align: center !important;
    position: relative !important;
    margin-bottom: 35px !important;
    box-shadow: 0 20px 40px rgba(15, 118, 110, 0.15) !important;
    min-height: 250px !important;
    display: flex !important;
    flex-direction: column !important;
    align-items: center !important;
    justify-content: center !important;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.05) !important;
}

.science-hero::after, .hero::after, .sj-hero-v6::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url("data:image/svg+xml,%3Csvg width='40' height='40' viewBox='0 0 40 40' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M0 40L40 0H20L0 20M40 40V20L20 40' fill='%23ffffff' fill-opacity='0.03'/%3E%3C/svg%3E");
    pointer-events: none;
}

.science-hero h1, .hero h1, .sj-hero-v6 h1 {
    font-size: clamp(2rem, 5vw, 3rem) !important;
    margin-bottom: 12px !important;
    font-family: var(--font-outfit) !important;
    z-index: 1 !important;
    font-weight: 800 !important;
    line-height: 1.2 !important;
    color: #fff !important;
    text-shadow: none !important;
    letter-spacing: -0.02em !important;
}

.science-hero p, .hero p, .sj-hero-v6 p {
    font-size: 0.95rem !important;
    opacity: 0.92 !important;
    z-index: 1 !important;
    max-width: 780px !important;
    margin: 0 auto !important;
    line-height: 1.65 !important;
    color: #f0fdfa !important;
}

.chapter-badge, .badge {
    display: inline-block;
    padding: 6px 16px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.2);
    font-size: 0.68rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #fff;
    font-family: var(--font-outfit);
    margin-bottom: 18px;
    z-index: 1;
}

/* ===== Premium Sticky Glassmorphism Tabs Navigation ===== */
.science-tabs, .tabs, .sj-section-nav {
    display: flex !important;
    flex-direction: row !important;
    flex-wrap: nowrap !important;
    gap: 8px !important;
    overflow-x: auto !important;
    padding: 6px !important;
    background: rgba(255, 255, 255, 0.8) !important;
    backdrop-filter: blur(20px) !important;
    -webkit-backdrop-filter: blur(20px) !important;
    border-radius: 50px !important;
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.03) !important;
    margin-bottom: 35px !important;
    scrollbar-width: none !important;
    position: sticky !important;
    top: 15px !important;
    z-index: 100 !important;
    -webkit-overflow-scrolling: touch !important;
    border: 1px solid rgba(226, 232, 240, 0.8) !important;
    transition: all 0.3s ease;
}

.science-tabs::-webkit-scrollbar, .tabs::-webkit-scrollbar, .sj-section-nav::-webkit-scrollbar {
    display: none !important;
}

.science-tab, .tab, .sj-section-link {
    flex: 0 0 auto !important;
    min-width: max-content !important;
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    gap: 8px !important;
    padding: 12px 22px !important;
    border: none !important;
    background: transparent !important;
    color: var(--sj-tab-text) !important;
    font-size: 0.82rem !important;
    font-weight: 700 !important;
    font-family: var(--font-outfit) !important;
    border-radius: 50px !important;
    cursor: pointer !important;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1) !important;
    white-space: nowrap !important;
    text-decoration: none !important;
    min-height: 44px !important;
}

.science-tab i, .tab i, .sj-section-link i {
    font-size: 0.9rem !important;
}

.science-tab:hover, .tab:hover, .sj-section-link:hover {
    background: var(--sj-tab-bg) !important;
    color: var(--sj-p) !important;
}

.science-tab.active, .tab.active, .sj-section-link.active {
    background: var(--sj-p) !important;
    color: #fff !important;
    box-shadow: 0 4px 16px rgba(15, 118, 110, 0.25) !important;
}

/* ===== Bento Layout Cards (Overview Category Display) ===== */
.science-grid, .grid, .sj-nav-grid {
    display: grid !important;
    grid-template-columns: 1fr !important;
    gap: 20px !important;
    margin-bottom: 40px !important;
}

@media (min-width: 640px) {
    .science-grid, .grid, .sj-nav-grid {
        grid-template-columns: repeat(2, 1fr) !important;
    }
}
@media (min-width: 1024px) {
    .science-grid, .grid, .sj-nav-grid {
        grid-template-columns: repeat(4, 1fr) !important;
    }
}

.topic-card, .sj-nav-card {
    background: #fff !important;
    border-radius: 20px !important;
    padding: 24px 20px !important;
    text-decoration: none !important;
    color: inherit !important;
    border: 1px solid rgba(226, 232, 240, 0.8) !important;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1) !important;
    display: flex !important;
    flex-direction: column !important;
    align-items: flex-start !important;
    gap: 15px !important;
    position: relative !important;
    overflow: hidden !important;
}

.topic-card:hover, .sj-nav-card:hover {
    border-color: var(--sj-pd) !important;
    transform: translateY(-4px) !important;
    box-shadow: 0 16px 32px rgba(15, 118, 110, 0.08) !important;
}

.topic-number, .num, .sj-nav-card-icon {
    width: 44px !important;
    height: 44px !important;
    border-radius: 12px !important;
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    font-size: 1.1rem !important;
    background: var(--sj-tab-bg) !important;
    color: var(--sj-p) !important;
    font-weight: 800 !important;
    flex-shrink: 0 !important;
    font-family: var(--font-outfit) !important;
}

.topic-card h3, .sj-nav-card h3 {
    font-family: var(--font-outfit) !important;
    font-size: 1.15rem !important;
    font-weight: 800 !important;
    margin-bottom: 2px !important;
    color: var(--sj-s) !important;
}

.topic-card p, .sj-nav-card p {
    font-size: 0.85rem !important;
    color: var(--science-muted) !important;
    line-height: 1.55 !important;
    margin: 0 !important;
}

/* ===== Standard Premium Content Cards ===== */
.science-card, .card, .sj-card {
    background: #fff !important;
    border-radius: 20px !important;
    border: 1px solid rgba(226, 232, 240, 0.8) !important;
    padding: 35px 30px !important;
    margin-bottom: 30px !important;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.02) !important;
}

.science-card h2, .card h2, .sj-card h2 {
    font-family: var(--font-outfit) !important;
    font-size: 1.5rem !important;
    font-weight: 800 !important;
    color: var(--sj-s) !important;
    border-bottom: 2px solid var(--sj-tab-bg) !important;
    padding-bottom: 12px !important;
    margin-bottom: 24px !important;
    margin-top: 0 !important;
    letter-spacing: -0.01em;
}

.science-card h3, .card h3, .sj-card h3 {
    font-family: var(--font-outfit) !important;
    font-size: 1.2rem !important;
    font-weight: 800;
    color: var(--sj-s) !important;
    margin: 28px 0 12px !important;
}

/* ===== Graded Solved Solution Details Boxes ===== */
.answer-box, .solution, details.example-solution, details.exercise-solution {
    margin-top: 14px !important;
    background: #f8fafc !important;
    border: 1px solid #e2e8f0 !important;
    border-radius: 12px !important;
    padding: 14px 18px !important;
    transition: all 0.25s ease !important;
}

.answer-box[open], .solution[open], details.example-solution[open], details.exercise-solution[open] {
    background: var(--sj-tab-bg) !important;
    border-color: var(--sj-pd) !important;
    box-shadow: 0 4px 12px rgba(15, 118, 110, 0.03) !important;
}

.answer-box summary, .solution summary, details summary {
    font-size: 0.9rem !important;
    font-weight: 700 !important;
    color: var(--sj-p) !important;
    cursor: pointer !important;
    outline: none !important;
    user-select: none !important;
    display: inline-flex !important;
    align-items: center !important;
    gap: 8px !important;
}

.solution-content, .answer-box p {
    margin-top: 14px !important;
    padding-top: 14px !important;
    border-top: 1px dashed #cbd5e1 !important;
    font-size: 0.92rem !important;
    color: #475569 !important;
    line-height: 1.65 !important;
    margin-bottom: 0 !important;
}

/* ===== Study Section Bottom Navigators ===== */
.bottom-nav, .sj-bottom-nav {
    display: flex !important;
    justify-content: space-between !important;
    align-items: center !important;
    margin-top: 35px !important;
    padding-top: 25px !important;
    border-top: 1px solid var(--sj-border) !important;
    gap: 15px !important;
}

.bottom-nav button, .bottom-nav a, .sj-bottom-nav button, .sj-bottom-nav a {
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    gap: 8px !important;
    padding: 12px 24px !important;
    border-radius: 50px !important;
    font-family: var(--font-outfit) !important;
    font-weight: 700 !important;
    font-size: 0.85rem !important;
    text-decoration: none !important;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1) !important;
    cursor: pointer !important;
    min-height: 44px !important;
    border: none !important;
}

/* Back navigation */
.bottom-nav button:first-child, .bottom-nav a.prev, .sj-bottom-nav button:first-child, .sj-bottom-nav a.prev {
    background: #f1f5f9 !important;
    color: #475569 !important;
    border: 1px solid #cbd5e1 !important;
}

.bottom-nav button:first-child:hover, .bottom-nav a.prev:hover, .sj-bottom-nav button:first-child:hover, .sj-bottom-nav a.prev:hover {
    background: #e2e8f0 !important;
    transform: translateY(-2px) !important;
}

/* Forward navigation */
.bottom-nav button:last-child, .bottom-nav a.next, .sj-bottom-nav button:last-child, .sj-bottom-nav a.next {
    background: var(--sj-p) !important;
    color: white !important;
    box-shadow: 0 4px 12px rgba(15, 118, 110, 0.2) !important;
}

.bottom-nav button:last-child:hover, .bottom-nav a.next:hover, .sj-bottom-nav button:last-child:hover, .sj-bottom-nav a.next:hover {
    background: var(--sj-pd) !important;
    transform: translateY(-2px) !important;
    box-shadow: 0 6px 16px rgba(15, 118, 110, 0.3) !important;
}

/* ===== Concept Definitions & Idea boxes ===== */
.definition, .idea {
    margin: 24px 0 !important;
    padding: 22px 26px !important;
    background: var(--sj-tab-bg) !important;
    border: 1px solid rgba(15, 118, 110, 0.15) !important;
    border-left: 5px solid var(--sj-p) !important;
    border-radius: 16px !important;
    font-size: 0.95rem !important;
    line-height: 1.7 !important;
    color: var(--sj-s) !important;
}

.idea {
    background: #f5f3ff !important;
    border-color: rgba(139, 92, 246, 0.12) !important;
    border-left-color: var(--sj-accent) !important;
}

.example {
    margin: 24px 0 !important;
    padding: 24px !important;
    background: var(--sj-bg) !important;
    border: 1px solid var(--sj-border) !important;
    border-radius: 16px !important;
}

.formula {
    margin: 24px 0 !important;
    padding: 24px !important;
    background: #fafaf9 !important;
    border-top: 1px solid var(--sj-border) !important;
    border-bottom: 1px solid var(--sj-border) !important;
    font-size: 1.25rem !important;
    border-radius: 14px !important;
    overflow-x: auto !important;
    text-align: center !important;
}

/* ===== Interactive Color-Coded Formula Breakdown Legends ===== */
.formula-legend {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 12px 18px;
    margin: 16px 0 24px;
    padding: 12px 18px;
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    font-size: 0.85rem;
    font-family: var(--font-outfit);
}

.legend-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: #475569;
    font-weight: 500;
}

.legend-item strong {
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 0.95rem;
    font-weight: 700;
    padding: 2px 6px;
    border-radius: 4px;
}

/* Harmonic color tokens for formulas */
.f-blue { color: #0284c7; background: #e0f2fe; }
.f-emerald { color: #059669; background: #d1fae5; }
.f-purple { color: #7c3aed; background: #ede9fe; }
.f-rose { color: #e11d48; background: #ffe4e6; }
.f-amber { color: #d97706; background: #fef3c7; }
.f-cyan { color: #0891b2; background: #cffafe; }

/* ===== Visual SVG Diagrams Container ===== */
.diagram-wrap {
    background: #f8fafc !important;
    border: 1px solid var(--sj-border) !important;
    border-radius: 16px !important;
    padding: 18px 16px !important;
    margin: 20px 0 !important;
    text-align: center !important;
    overflow: hidden !important;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.02) !important;
}

.diagram-wrap svg {
    width: 100% !important;
    max-width: 100% !important;
    height: auto !important;
    display: block !important;
    margin: 0 auto !important;
}

.diagram-caption {
    font-size: 0.85rem !important;
    font-weight: 600 !important;
    color: var(--science-muted) !important;
    margin-top: 10px !important;
    font-family: var(--font-outfit) !important;
}

/* ===== Interactive 3D Three.js Simulation Cards ===== */
.sim-3d-card {
    background: #090d16 !important;
    border: 1px solid #1e293b !important;
    border-radius: 16px !important;
    margin: 24px 0 !important;
    overflow: hidden !important;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25) !important;
}

.sim-3d-header {
    padding: 14px 18px !important;
    background: #0f172a !important;
    border-bottom: 1px solid #1e293b !important;
    display: flex !important;
    align-items: center !important;
    justify-content: space-between !important;
    gap: 12px !important;
    flex-wrap: wrap !important;
}

.sim-3d-title {
    font-family: var(--font-outfit) !important;
    font-size: 0.95rem !important;
    font-weight: 700 !important;
    color: #f8fafc !important;
    display: flex !important;
    align-items: center !important;
    gap: 8px !important;
    margin: 0 !important;
}

.sim-3d-badge {
    font-size: 0.7rem !important;
    font-weight: 700 !important;
    padding: 3px 8px !important;
    border-radius: 999px !important;
    background: rgba(56, 189, 248, 0.15) !important;
    color: #38bdf8 !important;
    border: 1px solid rgba(56, 189, 248, 0.3) !important;
    text-transform: uppercase !important;
    letter-spacing: 0.5px !important;
}

.sim-3d-canvas-wrap {
    position: relative !important;
    width: 100% !important;
    height: 360px !important;
    background: #0a0f1d !important;
    overflow: hidden !important;
}

.sim-3d-canvas-wrap canvas {
    width: 100% !important;
    height: 100% !important;
    display: block !important;
}

.sim-3d-hint {
    position: absolute !important;
    top: 10px !important;
    right: 12px !important;
    font-size: 0.72rem !important;
    color: #94a3b8 !important;
    background: rgba(15, 23, 42, 0.8) !important;
    backdrop-filter: blur(8px) !important;
    padding: 4px 10px !important;
    border-radius: 6px !important;
    border: 1px solid rgba(255, 255, 255, 0.1) !important;
    pointer-events: none !important;
    display: flex !important;
    align-items: center !important;
    gap: 5px !important;
}

.sim-3d-hud {
    padding: 12px 18px !important;
    background: #0b1120 !important;
    border-top: 1px solid #1e293b !important;
    font-size: 0.84rem !important;
    color: #cbd5e1 !important;
    line-height: 1.5 !important;
    font-family: var(--font-outfit) !important;
}

.sim-3d-hud .badge {
    padding: 2px 7px !important;
    border-radius: 4px !important;
    font-weight: 700 !important;
    font-family: 'JetBrains Mono', monospace !important;
    font-size: 0.82rem !important;
}
.badge-emerald { background: rgba(5, 150, 105, 0.2) !important; color: #34d399 !important; }
.badge-blue { background: rgba(2, 132, 199, 0.2) !important; color: #38bdf8 !important; }
.badge-amber { background: rgba(217, 119, 6, 0.2) !important; color: #fbbf24 !important; }
.badge-cyan { background: rgba(8, 145, 178, 0.2) !important; color: #22d3ee !important; }
.badge-rose { background: rgba(225, 29, 72, 0.2) !important; color: #fb7185 !important; }

.sim-3d-controls {
    padding: 12px 18px !important;
    background: #0f172a !important;
    border-top: 1px solid #1e293b !important;
    display: flex !important;
    align-items: center !important;
    justify-content: space-between !important;
    gap: 14px !important;
    flex-wrap: wrap !important;
}

.sim-control-group {
    display: flex !important;
    align-items: center !important;
    gap: 10px !important;
    font-size: 0.82rem !important;
    color: #cbd5e1 !important;
    flex-wrap: wrap !important;
}

.sim-btn {
    padding: 7px 14px !important;
    border-radius: 6px !important;
    background: #1e293b !important;
    color: #f8fafc !important;
    border: 1px solid #334155 !important;
    font-weight: 600 !important;
    font-size: 0.8rem !important;
    cursor: pointer !important;
    transition: all 0.15s ease !important;
    display: inline-flex !important;
    align-items: center !important;
    gap: 6px !important;
}
.sim-btn:hover { background: #334155 !important; }
.sim-btn.active {
    background: #0284c7 !important;
    color: #fff !important;
    border-color: #0284c7 !important;
}

.sim-slider {
    -webkit-appearance: none !important;
    appearance: none !important;
    height: 6px !important;
    border-radius: 3px !important;
    background: #334155 !important;
    outline: none !important;
    cursor: pointer !important;
    width: 120px !important;
}
.sim-slider::-webkit-slider-thumb {
    -webkit-appearance: none !important;
    width: 14px !important;
    height: 14px !important;
    border-radius: 50% !important;
    background: #38bdf8 !important;
    cursor: pointer !important;
}

/* High-Quality Tables */
.compare, .revision, .revision-table, .growth-table {
    width: 100% !important;
    margin: 24px 0 !important;
    border-collapse: separate !important;
    border-spacing: 0 !important;
    background: #fff !important;
    font-size: 0.9rem !important;
    border: 1px solid var(--sj-border) !important;
    border-radius: 16px !important;
    overflow: hidden !important;
    box-shadow: 0 4px 12px rgba(15, 23, 42, 0.01) !important;
}

.compare th, .revision th, .revision-table th, .growth-table th {
    background: var(--sj-bg) !important;
    color: var(--sj-s) !important;
    font-family: var(--font-outfit) !important;
    font-weight: 700 !important;
    border-bottom: 1.5px solid var(--sj-border) !important;
    padding: 14px 18px !important;
}

.compare td, .revision td, .revision-table td, .growth-table td {
    padding: 14px 18px !important;
    border-bottom: 1px solid var(--sj-border) !important;
    color: #475569 !important;
    line-height: 1.65 !important;
}



.timeline {
    position: relative !important;
    margin: 28px 0 !important;
    padding: 12px 0 !important;
}

.timeline::before {
    content: "" !important;
    position: absolute !important;
    left: 20px !important;
    top: 18px !important;
    bottom: 18px !important;
    width: 2px !important;
    background: #e2e8f0 !important;
}

.timeline-item {
    position: relative !important;
    display: grid !important;
    grid-template-columns: 44px 1fr !important;
    gap: 16px !important;
    margin-bottom: 24px !important;
}

.dot {
    z-index: 2 !important;
    width: 12px !important;
    height: 12px !important;
    margin: 8px 0 0 15px !important;
    border-radius: 50% !important;
    background: var(--sj-p) !important;
    box-shadow: 0 0 0 4px #fff, 0 0 0 6px rgba(15, 118, 110, 0.15) !important;
}

.coming-soon {
    text-align: center !important;
    padding: 64px 32px !important;
    border: 1px solid var(--sj-border) !important;
    border-radius: 20px !important;
    background: var(--sj-bg) !important;
}

.coming-soon i {
    font-size: 2.5rem !important;
    color: var(--sj-p) !important;
    margin-bottom: 16px !important;
}

.coming-soon h3 {
    font-family: var(--font-outfit) !important;
    margin: 8px 0 !important;
    color: var(--sj-s) !important;
}

.coming-soon p {
    color: var(--science-muted) !important;
    font-size: 0.95rem !important;
}

/* ===== Graded Practice Test Engine Styles ===== */
.test-selection-grid {
    display: grid !important;
    grid-template-columns: 1fr !important;
    gap: 20px !important;
    margin: 20px 0 !important;
}

@media (min-width: 768px) {
    .test-selection-grid {
        grid-template-columns: repeat(3, 1fr) !important;
    }
}

.sj-test-card {
    background: #fff !important;
    border-radius: 16px !important;
    border: 1px solid #e2e8f0 !important;
    padding: 22px !important;
    box-shadow: 0 4px 12px rgba(0,0,0,0.02) !important;
    display: flex !important;
    flex-direction: column !important;
    justify-content: space-between !important;
}

.sj-test-meta {
    display: flex !important;
    gap: 12px !important;
    font-size: 0.78rem !important;
    color: #64748b !important;
    margin: 12px 0 20px !important;
}

.sj-test-btn {
    padding: 10px 18px !important;
    border-radius: 50px !important;
    font-weight: 700 !important;
    font-size: 0.85rem !important;
    color: white !important;
    background: var(--sj-p) !important;
    border: none !important;
    cursor: pointer !important;
    transition: all 0.2s !important;
}

.sj-test-btn:hover {
    background: var(--sj-pd) !important;
    transform: translateY(-1px) !important;
}

.test-progress-bar {
    width: 100% !important;
    height: 8px !important;
    background: #e2e8f0 !important;
    border-radius: 4px !important;
    margin-bottom: 25px !important;
    overflow: hidden !important;
}

.test-progress-fill {
    height: 100% !important;
    background: linear-gradient(90deg, var(--sj-p), var(--sj-pd)) !important;
    width: 0% !important;
    transition: width 0.4s ease !important;
}

.option-button {
    display: block !important;
    width: 100% !important;
    padding: 14px 18px !important;
    background: #f8fafc !important;
    border: 2px solid #e2e8f0 !important;
    border-radius: 12px !important;
    text-align: left !important;
    font-size: 0.95rem !important;
    font-family: 'Poppins', sans-serif !important;
    color: #334155 !important;
    cursor: pointer !important;
    transition: all 0.2s ease !important;
    margin-bottom: 12px !important;
}

.option-button:hover:not(:disabled) {
    background: #f1f5f9 !important;
    border-color: #cbd5e1 !important;
    transform: translateX(4px) !important;
}

.option-button.selected {
    background: var(--sj-tab-bg) !important;
    border-color: var(--sj-p) !important;
    color: var(--sj-p) !important;
    font-weight: 600 !important;
}

.grading-option {
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    padding: 8px 16px !important;
    border-radius: 50px !important;
    font-size: 0.82rem !important;
    font-weight: 700 !important;
    cursor: pointer !important;
    border: 2px solid #cbd5e1 !important;
    background: #fff !important;
    transition: all 0.2s !important;
    margin-right: 8px !important;
    margin-top: 8px !important;
}

.grading-option.active-full {
    border-color: #10b981 !important;
    background: #ecfdf5 !important;
    color: #065f46 !important;
}

.grading-option.active-half {
    border-color: #f59e0b !important;
    background: #fffbeb !important;
    color: #78350f !important;
}

.grading-option.active-zero {
    border-color: #ef4444 !important;
    background: #fef2f2 !important;
    color: #991b1b !important;
}

.test-action-btn {
    background: var(--sj-p) !important;
    color: white !important;
    border: none !important;
    padding: 12px 24px !important;
    font-family: var(--font-outfit) !important;
    font-weight: 700 !important;
    font-size: 0.9rem !important;
    border-radius: 50px !important;
    cursor: pointer !important;
    transition: all 0.2s ease !important;
}

.test-action-btn:hover {
    background: var(--sj-pd) !important;
    transform: translateY(-1px) !important;
}

/* ===== GLOBAL DARK MODE STYLING & ACCENT CONTRAST ===== */
body.dark-mode {
    background-color: #0f172a !important;
    color: #cbd5e1 !important;
}

body.dark-mode p {
    color: #94a3b8 !important;
}

body.dark-mode strong, body.dark-mode b {
    color: #f8fafc !important;
}

body.dark-mode .science-card, body.dark-mode .card, body.dark-mode .sj-card,
body.dark-mode .topic-card, body.dark-mode .sj-nav-card, body.dark-mode .sj-tbar {
    background: #1e293b !important;
    border-color: #334155 !important;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25) !important;
}

body.dark-mode .science-card h2, body.dark-mode .card h2, body.dark-mode .sj-card h2 {
    color: #f8fafc !important;
    border-bottom-color: #334155 !important;
}

body.dark-mode .science-card h3, body.dark-mode .card h3, body.dark-mode .sj-card h3,
body.dark-mode .topic-card h3, body.dark-mode .sj-nav-card h3 {
    color: #f1f5f9 !important;
}

body.dark-mode .science-tabs, body.dark-mode .tabs, body.dark-mode .sj-section-nav {
    background: rgba(30, 41, 59, 0.8) !important;
    border-color: #334155 !important;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3) !important;
}

body.dark-mode .science-tab, body.dark-mode .tab, body.dark-mode .sj-section-link {
    color: #94a3b8 !important;
}

body.dark-mode .science-tab:hover, body.dark-mode .tab:hover, body.dark-mode .sj-section-link:hover {
    color: var(--sj-pd) !important;
    background: rgba(15, 118, 110, 0.15) !important;
}

body.dark-mode .science-tab.active, body.dark-mode .tab.active, body.dark-mode .sj-section-link.active {
    background: var(--sj-p) !important;
    color: #fff !important;
    box-shadow: 0 4px 12px rgba(15, 118, 110, 0.3) !important;
}

body.dark-mode .definition, body.dark-mode .idea {
    background: #112d2b !important;
    border-color: rgba(15, 118, 110, 0.3) !important;
    color: #e2e8f0 !important;
}

body.dark-mode .idea {
    background: #251b40 !important;
    border-color: rgba(139, 92, 246, 0.25) !important;
}

body.dark-mode .example,
body.dark-mode .coming-soon, body.dark-mode .solution, body.dark-mode .answer-box {
    background: #0f172a !important;
    border-color: #334155 !important;
    color: #cbd5e1 !important;
}

body.dark-mode .formula {
    background: #0f172a !important;
    border-color: #334155 !important;
    color: #f1f5f9 !important;
}

body.dark-mode .compare, body.dark-mode .revision,
body.dark-mode .revision-table, body.dark-mode .growth-table {
    background: #1e293b !important;
    border-color: #334155 !important;
}

body.dark-mode .compare th, body.dark-mode .revision th,
body.dark-mode .revision-table th, body.dark-mode .growth-table th {
    background: #0f172a !important;
    color: #f1f5f9 !important;
    border-bottom-color: #334155 !important;
}

body.dark-mode .compare td, body.dark-mode .revision td,
body.dark-mode .revision-table td, body.dark-mode .growth-table td {
    border-bottom-color: #334155 !important;
    color: #cbd5e1 !important;
}

body.dark-mode .sj-btn, body.dark-mode .bottom-nav button, body.dark-mode .bottom-nav a,
body.dark-mode .sj-bottom-nav button, body.dark-mode .sj-bottom-nav a {
    background: #1e293b !important;
    border-color: #475569 !important;
    color: #f1f5f9 !important;
}

body.dark-mode .sj-btn:hover, body.dark-mode .bottom-nav button:hover, body.dark-mode .bottom-nav a:hover,
body.dark-mode .sj-bottom-nav button:hover, body.dark-mode .sj-bottom-nav a:hover {
    background: var(--sj-tab-bg) !important;
    border-color: var(--sj-p) !important;
    color: var(--sj-p) !important;
}






body.dark-mode .timeline::before {
    background: #334155 !important;
}

body.dark-mode .dot {
    box-shadow: 0 0 0 4px #1e293b, 0 0 0 6px rgba(15, 118, 110, 0.25) !important;
}

body.dark-mode .readout-chip {
    background: rgba(15, 118, 110, 0.15) !important;
    border-color: rgba(15, 118, 110, 0.25) !important;
    color: #34d399 !important;
}

/* ===== Interactive diagrams and visual containers ===== */
.diagram, .visual-card {
    background: #ffffff !important;
    border: 1px solid var(--sj-border) !important;
    border-radius: 18px !important;
    padding: 24px !important;
    margin: 28px 0 !important;
    box-shadow: 0 4px 20px rgba(15, 23, 42, 0.02) !important;
    position: relative !important;
}

.diagram-title {
    font-family: var(--font-outfit) !important;
    font-size: 0.88rem !important;
    font-weight: 800 !important;
    color: var(--sj-p) !important;
    text-transform: uppercase !important;
    letter-spacing: 0.05em !important;
    margin-bottom: 16px !important;
}

.visual-stage {
    background: #f8fafc !important;
    border: 1px solid #e2e8f0 !important;
    border-radius: 12px !important;
    padding: 15px !important;
    margin: 15px 0 !important;
    overflow-x: auto !important;
}

.figure-caption, .caption {
    font-size: 0.82rem !important;
    color: var(--science-muted) !important;
    margin-top: 12px !important;
    line-height: 1.5 !important;
}

.controls, .animation-controls {
    display: flex !important;
    gap: 8px !important;
    margin-top: 15px !important;
    flex-wrap: wrap !important;
}

.controls button, .animation-controls button {
    border: 1.5px solid #cbd5e1 !important;
    border-radius: 50px !important;
    padding: 8px 16px !important;
    background: #fff !important;
    color: #475569 !important;
    font-family: var(--font-outfit) !important;
    font-weight: 700 !important;
    font-size: 0.8rem !important;
    cursor: pointer !important;
    transition: all 0.2s ease !important;
}

.controls button:hover, .animation-controls button:hover {
    background: var(--sj-tab-bg) !important;
    color: var(--sj-p) !important;
    border-color: var(--sj-p) !important;
    transform: translateY(-1px) !important;
}

body.dark-mode .diagram, body.dark-mode .visual-card {
    background: #1e293b !important;
    border-color: #334155 !important;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2) !important;
}

body.dark-mode .visual-stage {
    background: #0f172a !important;
    border-color: #334155 !important;
}

body.dark-mode .controls button, body.dark-mode .animation-controls button {
    background: #1e293b !important;
    border-color: #475569 !important;
    color: #cbd5e1 !important;
}

body.dark-mode .controls button:hover, body.dark-mode .animation-controls button:hover {
    background: rgba(15, 118, 110, 0.2) !important;
    color: var(--sj-p) !important;
    border-color: var(--sj-p) !important;
}

/* ===== Tab Pane Display Visibility Styles ===== */
.tab-pane, .pane {
    display: none;
    animation: fadeInTab 0.35s ease;
}

.tab-pane.active, .pane.active {
    display: block;
}

@keyframes fadeInTab {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===== Print styles ===== */
@media print {
    body {
        background: #fff !important;
    }
    .science-tabs, .tabs, .sj-section-nav, .sj-tbar, .bottom-nav, .sj-bottom-nav, .solution-btn, .controls {
        display: none !important;
    }
    .tab-pane, .pane {
        display: block !important;
    }
    .answer-box, .solution, details.example-solution, details.exercise-solution {
        display: block !important;
    }
}