/*
 * IntelliBlink - Dark Cinematic Homepage
 * Inspired by antigravity.google aesthetic
 * Dark immersive theme with scroll-driven reveals
 */

/* [Performance Fix] Removed Google Fonts import to prevent timeouts in offline environments */

/* ========================================
   CSS Custom Properties (Dark Theme)
   ======================================== */
:root {
    /* Dark backgrounds */
    --dark-bg: #06060a;
    --dark-surface: #0d0d14;
    --dark-surface-2: #13131d;
    --dark-surface-3: #1a1a28;
    --dark-elevated: #22222f;

    /* Primary accent - electric blue */
    --accent: #3b82f6;
    --accent-light: #60a5fa;
    --accent-lighter: #93bbfd;
    --accent-glow: rgba(59, 130, 246, 0.15);
    --accent-glow-strong: rgba(59, 130, 246, 0.3);

    /* Text on dark */
    --text-bright: #f1f5f9;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --text-dim: #475569;

    /* Borders */
    --border-subtle: rgba(255, 255, 255, 0.06);
    --border-light: rgba(255, 255, 255, 0.1);
    --border-accent: rgba(59, 130, 246, 0.3);

    /* Sizing */
    --container-max: 1200px;
    --container-wide: 1400px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    /* Shadows for dark theme */
    --shadow-glow: 0 0 60px rgba(59, 130, 246, 0.08);
    --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);
    --shadow-card-hover: 0 8px 40px rgba(0, 0, 0, 0.6);
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body.dark-home {
    /* Use system font stack for offline performance */
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
    background: var(--dark-bg);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

a { text-decoration: none; color: inherit; transition: all 0.3s ease; }
ul { list-style: none; }
img { max-width: 100%; height: auto; }

.container-dark {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 32px;
}

.container-wide {
    max-width: var(--container-wide);
    margin: 0 auto;
    padding: 0 32px;
}

/* ========================================
   Scroll Reveal Animation System
   ======================================== */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
                transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }

.reveal-scale {
    opacity: 0;
    transform: scale(0.92);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
                transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal-scale.visible {
    opacity: 1;
    transform: scale(1);
}

/* ========================================
   Navigation
   ======================================== */
.nav-dark {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 0 32px;
    height: 72px;
    display: flex;
    align-items: center;
    transition: background 0.4s ease, backdrop-filter 0.4s ease, border-color 0.4s ease;
    border-bottom: 1px solid transparent;
    /* Hardware acceleration to fix mobile rendering */
    transform: translateZ(0);
    -webkit-transform: translateZ(0);
}

.nav-dark.scrolled {
    background: rgba(6, 6, 10, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom-color: var(--border-subtle);
}

.nav-dark-inner {
    max-width: var(--container-wide);
    width: 100%;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-dark-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 18px;
    color: var(--text-bright);
    letter-spacing: -0.3px;
}

.nav-dark-logo img {
    width: 32px;
    height: 32px;
    object-fit: contain;
}

.nav-dark-links {
    display: flex;
    align-items: center;
    gap: 36px;
}

.nav-dark-links a {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-muted);
    transition: color 0.2s;
}

.nav-dark-links a:hover {
    color: var(--text-bright);
}

.nav-dark-cta {
    padding: 9px 22px;
    background: var(--accent);
    color: white !important;
    border-radius: 50px;
    font-size: 13px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 0 20px rgba(59, 130, 246, 0.25);
}

.nav-dark-cta:hover {
    background: var(--accent-light);
    box-shadow: 0 0 30px rgba(59, 130, 246, 0.4);
    transform: translateY(-1px);
}

/* Mobile Toggle */
.nav-mobile-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-bright);
    font-size: 24px;
    cursor: pointer;
    padding: 8px;
    transition: color 0.2s;
}

.nav-mobile-toggle:hover {
    color: var(--accent);
}

/* ========================================
   HERO Section
   ======================================== */
.hero-dark {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 32px 80px;
    overflow: hidden;
}

/* Grid background */
.hero-dark::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(59, 130, 246, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(59, 130, 246, 0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 30%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 30%, transparent 70%);
}

/* Top glow */
.hero-dark::after {
    content: '';
    position: absolute;
    top: -200px;
    left: 50%;
    transform: translateX(-50%);
    width: 1000px;
    height: 800px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.08) 0%, rgba(59, 130, 246, 0.02) 40%, transparent 70%);
    pointer-events: none;
}

.hero-dark-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 20px;
    background: var(--dark-surface-2);
    border: 1px solid var(--border-light);
    border-radius: 50px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.hero-badge-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 8px rgba(34, 197, 94, 0.5);
    animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

.hero-dark-title {
    font-size: clamp(48px, 7vw, 80px);
    font-weight: 800;
    line-height: 1.05;
    letter-spacing: -2px;
    color: var(--text-bright);
    margin-bottom: 28px;
}

.hero-dark-title .accent-text {
    background: linear-gradient(135deg, var(--accent-light), #a78bfa, var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-dark-subtitle {
    font-size: clamp(17px, 2vw, 20px);
    font-weight: 400;
    color: var(--text-secondary);
    max-width: 640px;
    margin: 0 auto 48px;
    line-height: 1.7;
}

.hero-buttons-dark {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.btn-dark-primary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    background: white;
    color: #0a0a0f;
    border-radius: 50px;
    font-weight: 600;
    font-size: 15px;
    transition: all 0.3s ease;
    border: none;
}

.btn-dark-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(255, 255, 255, 0.15);
}

.btn-dark-secondary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-light);
    border-radius: 50px;
    font-weight: 600;
    font-size: 15px;
    transition: all 0.3s ease;
}

.btn-dark-secondary:hover {
    border-color: var(--text-secondary);
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-2px);
}

/* ========================================
   Stats Bar
   ======================================== */
.stats-dark {
    border-top: 1px solid var(--border-subtle);
    border-bottom: 1px solid var(--border-subtle);
    background: var(--dark-surface);
    padding: 48px 0;
}

.stats-dark-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
}

.stat-dark-item {
    text-align: center;
}

.stat-dark-number {
    font-size: 40px;
    font-weight: 800;
    color: var(--text-bright);
    letter-spacing: -1.5px;
    line-height: 1;
    margin-bottom: 8px;
}

.stat-dark-number .stat-unit {
    font-size: 24px;
    font-weight: 600;
    color: var(--accent-light);
}

.stat-dark-label {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
}

/* ========================================
   Section Common
   ======================================== */
.section-dark {
    padding: 120px 0;
    position: relative;
}

.section-dark-alt {
    background: var(--dark-surface);
}

.section-header-dark {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 80px;
}

.section-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2.5px;
    color: var(--accent-light);
    margin-bottom: 20px;
}

.section-title-dark {
    font-size: clamp(32px, 4vw, 48px);
    font-weight: 800;
    color: var(--text-bright);
    letter-spacing: -1px;
    line-height: 1.15;
    margin-bottom: 20px;
}

.section-subtitle-dark {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ========================================
   Features - Alternating Layout
   ======================================== */
.feature-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    margin-bottom: 120px;
}

.feature-row:last-child {
    margin-bottom: 0;
}

.feature-row.reverse .feature-visual {
    order: -1;
}

.feature-text {
    max-width: 480px;
}

.feature-icon-dark {
    width: 52px;
    height: 52px;
    background: var(--accent-glow);
    border: 1px solid var(--border-accent);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--accent-light);
    margin-bottom: 24px;
}

.feature-name {
    font-size: 14px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--accent-light);
    margin-bottom: 12px;
}

.feature-title-dark {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-bright);
    letter-spacing: -0.5px;
    line-height: 1.2;
    margin-bottom: 20px;
}

.feature-desc-dark {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 28px;
}

.feature-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.feature-tag {
    padding: 6px 14px;
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    border-radius: 50px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
}

.feature-more-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 20px;
    font-size: 14px;
    font-weight: 500;
    color: var(--accent-light);
    text-decoration: none;
    transition: all 0.3s ease;
}

.feature-more-link:hover {
    color: var(--accent);
    gap: 10px;
}

.feature-more-link i {
    font-size: 16px;
    transition: transform 0.3s ease;
}

.feature-more-link:hover i {
    transform: translateX(4px);
}

/* Feature visual cards */
.feature-visual {
    position: relative;
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    padding: 40px;
    min-height: 360px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.feature-visual::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 50% 50%, var(--accent-glow) 0%, transparent 70%);
    pointer-events: none;
}

.feature-visual-inner {
    position: relative;
    z-index: 1;
    text-align: center;
}

.feature-visual-icon {
    font-size: 80px;
    color: var(--accent);
    margin-bottom: 20px;
    opacity: 0.7;
}

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

.fv-chip {
    padding: 10px 16px;
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    text-align: center;
    transition: all 0.3s ease;
}

.fv-chip:hover {
    border-color: var(--border-accent);
    color: var(--accent-light);
    background: rgba(59, 130, 246, 0.08);
}

.fv-chip.highlight {
    border-color: var(--border-accent);
    color: var(--accent-light);
    background: var(--accent-glow);
}

/* ========================================
   Feature Bento Grid (compact features)
   ======================================== */
.bento-grid-dark {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.bento-card-dark {
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 36px 32px;
    transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    position: relative;
    overflow: hidden;
}

.bento-card-dark::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent-glow-strong), transparent);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.bento-card-dark:hover {
    border-color: var(--border-accent);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.bento-card-dark:hover::before {
    opacity: 1;
}

a.bento-card-link {
    text-decoration: none;
    color: inherit;
    display: block;
    cursor: pointer;
}

a.bento-card-link:hover .bento-title-dark {
    color: var(--accent-light);
}

.bento-icon-dark {
    width: 44px;
    height: 44px;
    background: var(--accent-glow);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    color: var(--accent-light);
    margin-bottom: 20px;
}

.bento-title-dark {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 10px;
}

.bento-desc-dark {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
}

/* ========================================
   Cases Showcase
   ======================================== */
.cases-showcase {
    padding: 120px 0;
    background: var(--dark-surface);
}

.cases-scroll {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.case-dark-card {
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    display: flex;
    flex-direction: column;
}

.case-dark-card:hover {
    border-color: var(--border-accent);
    transform: translateY(-6px);
    box-shadow: var(--shadow-card-hover);
}

.case-dark-image {
    position: relative;
    height: 200px;
    overflow: hidden;
    background: var(--dark-surface-3);
    display: flex;
    align-items: center;
    justify-content: center;
}

.case-dark-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.case-dark-card:hover .case-dark-image img {
    transform: scale(1.05);
}

.case-dark-body {
    padding: 24px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.case-dark-category {
    display: inline-block;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent-light);
    margin-bottom: 10px;
}

.case-dark-title {
    font-size: 17px;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 8px;
    line-height: 1.4;
}

.case-dark-desc {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.6;
    flex: 1;
}

.case-dark-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    font-weight: 600;
    color: var(--accent-light);
    margin-top: 16px;
    transition: gap 0.2s ease;
}

.case-dark-link:hover {
    gap: 10px;
}

/* ========================================
   Categories Navigation
   ======================================== */
.categories-dark {
    padding: 120px 0;
}

.categories-dark-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 16px;
}

.category-dark-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 36px 20px;
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.category-dark-card:hover {
    border-color: var(--border-accent);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.category-dark-icon {
    width: 56px;
    height: 56px;
    background: var(--accent-glow);
    border: 1px solid var(--border-accent);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 26px;
    color: var(--accent-light);
    margin-bottom: 16px;
    transition: all 0.3s ease;
}

.category-dark-card:hover .category-dark-icon {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
    transform: scale(1.08);
}

.category-dark-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 6px;
}

.category-dark-count {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 500;
}

/* ========================================
   CTA Section
   ======================================== */
.cta-dark {
    padding: 120px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    background: var(--dark-surface);
}

.cta-dark::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 800px;
    height: 600px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 60%);
    pointer-events: none;
}

.cta-dark-content {
    position: relative;
    z-index: 1;
}

.cta-dark-title {
    font-size: clamp(32px, 4vw, 48px);
    font-weight: 800;
    color: var(--text-bright);
    letter-spacing: -1px;
    margin-bottom: 16px;
}

.cta-dark-desc {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

/* ========================================
   Footer
   ======================================== */
.footer-dark {
    border-top: 1px solid var(--border-subtle);
    padding: 48px 0;
    text-align: center;
}

.footer-dark-text {
    font-size: 14px;
    color: var(--text-dim);
    margin-bottom: 12px;
}

.footer-dark-links {
    display: flex;
    justify-content: center;
    gap: 24px;
}

.footer-dark-links a {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
}

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

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 1024px) {
    .feature-row {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .feature-row.reverse .feature-visual {
        order: 0;
    }

    .feature-text {
        max-width: 100%;
    }

    .bento-grid-dark {
        grid-template-columns: repeat(2, 1fr);
    }

    .categories-dark-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .cases-scroll {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .container-dark,
    .container-wide {
        padding: 0 20px;
    }

    /* Mobile: nav always has glassmorphism background */
    .nav-dark {
        position: fixed !important;
        top: 0;
        left: 0;
        width: 100%;
        z-index: 9999 !important;
        padding: 0 20px;
        background: rgba(6, 6, 10, 0.75);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        border-bottom: 1px solid var(--border-subtle);
    }

    .nav-mobile-toggle {
        display: block;
    }

    /* Mobile: hide horizontal links, show as fullscreen menu when active */
    .nav-dark-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        height: calc(100vh - 72px);
        height: calc(100dvh - 72px);
        background: var(--dark-bg);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        padding: 40px;
        z-index: 999;
        overflow-y: auto;
    }

    .nav-dark-links.active {
        display: flex;
        animation: navSlideDown 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    }

    @keyframes navSlideDown {
        from { opacity: 0; transform: translateY(-20px); }
        to { opacity: 1; transform: translateY(0); }
    }

    .nav-dark-links a {
        font-size: 18px;
        font-weight: 600;
        color: var(--text-primary);
    }

    .nav-dark-links a:hover {
        color: var(--text-bright);
    }

    .nav-dark-cta {
        width: 100%;
        text-align: center;
        max-width: 240px;
        padding: 14px 0 !important;
        font-size: 16px !important;
        margin-top: 10px;
    }

    .hero-dark {
        padding: 100px 20px 60px;
        min-height: auto;
    }

    .hero-dark-title {
        letter-spacing: -1px;
    }

    .hero-buttons-dark {
        flex-direction: column;
        align-items: center;
    }

    .stats-dark-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 24px;
    }

    .section-dark {
        padding: 80px 0;
    }

    .bento-grid-dark {
        grid-template-columns: 1fr;
    }

    .cases-scroll {
        grid-template-columns: 1fr;
    }

    .categories-dark-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .feature-visual {
        min-height: 260px;
        padding: 24px;
    }

    .feature-visual-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .stats-dark-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    .stat-dark-number {
        font-size: 28px;
    }

    .categories-dark-grid {
        grid-template-columns: 1fr;
    }
}

/* ========================================
   Particle Background (Case Library)
   ======================================== */
.particle-bg-wrap {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

.particle-bg-wrap canvas {
    display: block;
    width: 100%;
    height: 100%;
}

/* Ensure all content sits above particles */
.container-dark,
.footer-dark {
    position: relative;
    z-index: 1;
}

/* ========================================
   Case Library Page (index.html) - Showcase
   ======================================== */

/* --- Showcase Container --- */
.showcase-container {
    position: relative;
    z-index: 1;
    display: flex;
    align-items: center;
    min-height: 100vh;
    padding: 120px var(--page-margin, 40px) 100px;
    max-width: var(--container-wide);
    margin: 0 auto;
    gap: 60px;
}

.showcase-visual {
    flex: 1 1 55%;
    /* transparent area -- canvas shows through */
    min-height: 400px;
}

.showcase-info {
    flex: 0 0 40%;
    max-width: 480px;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.showcase-info.transitioning {
    opacity: 0;
    transform: translateY(12px);
}

/* --- Category Badge --- */
.showcase-category {
    display: inline-block;
    padding: 6px 16px;
    border-radius: 50px;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    margin-bottom: 20px;
    /* default color, overridden by JS */
    background: rgba(59, 130, 246, 0.15);
    color: #60a5fa;
}

/* --- Title, Description, CTA --- */
.showcase-title {
    font-size: clamp(28px, 4vw, 42px);
    font-weight: 800;
    color: var(--text-bright);
    line-height: 1.3;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.showcase-desc {
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: 32px;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* --- Search Input (Stealth Pill) --- */
.showcase-search {
    position: relative;
    margin-bottom: 24px;
    max-width: 300px;
    width: 100%;
}

.showcase-search i {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    font-size: 16px;
    pointer-events: none;
    transition: color 0.2s;
}

.showcase-search input {
    width: 100%;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-subtle);
    border-radius: 50px;
    padding: 10px 16px 10px 42px; /* Space for icon */
    font-size: 14px;
    color: var(--text-bright);
    outline: none;
    transition: all 0.2s ease;
    font-family: inherit;
}

.showcase-search input::placeholder {
    color: var(--text-muted);
    opacity: 0.6;
}

.showcase-search input:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--text-secondary);
}

.showcase-search input:focus {
    background: rgba(255, 255, 255, 0.12);
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.showcase-search input:focus + i,
.showcase-search:focus-within i {
    color: var(--accent);
}

.showcase-cta {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    background: var(--accent);
    color: white;
    border-radius: var(--radius-md);
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    margin-bottom: 40px;
}
.showcase-cta:hover {
    background: var(--accent-light);
    transform: translateX(4px);
}

/* --- Navigation Arrows + Counter --- */
.showcase-nav {
    display: flex;
    align-items: center;
    gap: 16px;
}

.showcase-arrow {
    width: 44px; height: 44px;
    border-radius: 50%;
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
}
.showcase-arrow:hover {
    border-color: var(--accent);
    color: var(--accent-light);
    background: var(--dark-surface-2);
}

.showcase-counter {
    font-size: 14px;
    color: var(--text-muted);
    font-variant-numeric: tabular-nums;
    min-width: 60px;
    text-align: center;
}

/* --- Category Bar (fixed bottom) --- */
.category-bar {
    position: fixed;
    bottom: 0; left: 0;
    width: 100%;
    z-index: 10;
    background: rgba(6, 6, 10, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 1px solid var(--border-subtle);
    padding: 16px 0 12px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.category-tabs {
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
    justify-content: center;
    padding: 0 20px;
}

.cat-tab {
    padding: 8px 18px;
    background: transparent;
    border: 1px solid transparent;
    border-radius: 50px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}
.cat-tab:hover {
    color: var(--text-primary);
}
.cat-tab.active {
    background: var(--accent);
    color: white;
    box-shadow: 0 0 16px rgba(59, 130, 246, 0.25);
}

.dot-indicators {
    display: flex;
    gap: 6px;
    justify-content: center;
    max-width: 80%;
    flex-wrap: wrap;
}

.dot-indicator {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    cursor: pointer;
    transition: all 0.3s;
}
.dot-indicator:hover {
    background: var(--text-muted);
}
.dot-indicator.active {
    background: var(--accent);
    border-color: var(--accent);
    transform: scale(1.3);
}

/* --- Showcase Responsive --- */
@media (max-width: 1024px) {
    .showcase-container {
        flex-direction: column;
        padding-top: 100px;
        padding-bottom: 140px;
        gap: 30px;
    }
    .showcase-visual {
        min-height: 250px;
        flex: 0 0 auto;
    }
    .showcase-info {
        flex: 0 0 auto;
        max-width: 100%;
        text-align: center;
        /* 窄屏防御性毛玻璃背景，确保文字在粒子上方可读 */
        background: rgba(6, 6, 10, 0.75);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        border-radius: var(--radius-lg);
        padding: 28px;
    }
    .showcase-nav {
        justify-content: center;
    }
}
@media (max-width: 768px) {
    .showcase-container {
        padding: 80px 20px 160px;
    }
    .showcase-visual {
        min-height: 200px;
    }
    .category-tabs {
        gap: 2px;
    }
    .cat-tab {
        padding: 6px 12px;
        font-size: 12px;
    }
}

/* ========================================
   Feature Detail Pages
   ======================================== */
.feature-page-hero {
    padding: 140px 0 60px;
    text-align: center;
    position: relative;
    border-bottom: 1px solid var(--border-subtle);
}

.feature-page-hero::after {
    content: '';
    position: absolute;
    top: -100px;
    left: 50%;
    transform: translateX(-50%);
    width: 700px;
    height: 500px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.07) 0%, transparent 65%);
    pointer-events: none;
}

.feature-page-hero h1 {
    font-size: clamp(36px, 5vw, 56px);
    font-weight: 800;
    color: var(--text-bright);
    letter-spacing: -1px;
    margin-bottom: 16px;
    position: relative;
}

.feature-page-hero p {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
    position: relative;
}

.feature-body {
    padding: 80px 0;
}

.feature-body-content {
    max-width: 760px;
    margin: 0 auto;
}

/* Feature body content styling for structured text */
.feature-body-content h3 {
    font-size: 22px;
    font-weight: 700;
    color: var(--text-bright);
    margin-top: 48px;
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.feature-body-content h3::before {
    content: '';
    display: block;
    width: 4px;
    height: 24px;
    background: linear-gradient(to bottom, var(--accent), var(--accent-light));
    border-radius: 2px;
}

.feature-body-content ul {
    list-style: none;
    padding: 0;
    margin-bottom: 32px;
}

.feature-body-content li {
    position: relative;
    padding-left: 28px;
    margin-bottom: 16px;
    color: var(--text-secondary);
    line-height: 1.7;
}

.feature-body-content li::before {
    content: '\eb7b'; /* remixicon check-line */
    font-family: 'remixicon';
    position: absolute;
    left: 0;
    top: 2px;
    color: var(--accent);
    font-size: 18px;
    font-weight: normal;
}

.feature-body-content li strong {
    color: var(--text-bright);
    font-weight: 600;
}

.feature-body-content p {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

/* Feature case cards */
.feature-cases-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    max-width: 760px;
    margin: 0 auto;
}

.feature-case-card {
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: all 0.3s ease;
    display: block;
}

.feature-case-card:hover {
    border-color: var(--border-accent);
    box-shadow: var(--shadow-glow);
}

.feature-case-card .fc-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 4px;
}

.feature-case-card .fc-subtitle {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.feature-case-card .fc-images {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 16px;
}

.feature-case-card .fc-images img {
    width: 100%;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-subtle);
}

.feature-case-card .fc-desc {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
}

.feature-case-card .fc-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.feature-case-card .fc-tag {
    padding: 4px 12px;
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    border-radius: 50px;
    font-size: 12px;
    color: var(--text-muted);
}

/* Benefits grid on feature pages */
.benefits-dark-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    max-width: 900px;
    margin: 0 auto;
}

.benefit-dark-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 28px 20px;
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    transition: all 0.3s ease;
}

.benefit-dark-card:hover {
    border-color: var(--border-accent);
    transform: translateY(-2px);
}

.benefit-dark-card i {
    font-size: 28px;
    color: var(--accent-light);
    margin-bottom: 12px;
}

.benefit-dark-card .bd-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-bright);
    margin-bottom: 6px;
}

.benefit-dark-card .bd-desc {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.5;
}

@media (max-width: 768px) {
    .benefits-dark-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .feature-case-card .fc-images {
        grid-template-columns: 1fr;
    }
}

/* ========================================
   Case Detail Pages (generated by Python)
   ======================================== */

/* --- Hero: Enhanced with glow & grid (matches home-ag) --- */
.case-detail-hero {
    padding: 110px 0 40px;
    border-bottom: 1px solid var(--border-subtle);
    position: relative;
    overflow: hidden;
}

.case-detail-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(59, 130, 246, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(59, 130, 246, 0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse 80% 70% at 50% 50%, black 20%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 50%, black 20%, transparent 70%);
    pointer-events: none;
}

.case-detail-hero::after {
    content: '';
    position: absolute;
    top: -120px;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 600px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.08) 0%, rgba(59, 130, 246, 0.02) 40%, transparent 70%);
    pointer-events: none;
}

.case-detail-hero .container-dark {
    position: relative;
    z-index: 1;
    max-width: 1100px;
    padding: 0 32px;
}

.case-detail-hero .case-category-badge {
    display: inline-block;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent-light);
    background: var(--accent-glow);
    border: 1px solid var(--border-accent);
    padding: 6px 16px;
    border-radius: 50px;
    margin-top: 24px;
    margin-bottom: 20px;
    animation: caseBadgeFadeIn 0.6s 0.2s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes caseBadgeFadeIn {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

.case-detail-hero h1 {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 800;
    color: var(--text-bright);
    letter-spacing: -1px;
    line-height: 1.2;
    animation: caseHeroTitleIn 0.8s 0.35s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes caseHeroTitleIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- Breadcrumb --- */
.case-breadcrumb {
    padding: 16px 0 0;
    position: relative;
    z-index: 1;
}

.case-breadcrumb ol {
    display: flex;
    align-items: center;
    gap: 0;
    list-style: none;
    margin: 0;
    padding: 0;
    font-size: 13px;
    flex-wrap: wrap;
}

.case-breadcrumb li {
    display: flex;
    align-items: center;
    color: var(--text-muted);
    margin: 0;
    line-height: 1.5;
}

.case-breadcrumb li + li::before {
    content: '\ea6e'; /* ri-arrow-right-s-line */
    font-family: 'remixicon';
    margin: 0 8px;
    font-size: 14px;
    color: var(--text-dim);
}

.case-breadcrumb a {
    color: var(--text-muted);
    font-weight: 500;
    transition: color 0.2s;
}

.case-breadcrumb a:hover {
    color: var(--accent-light);
}

.case-breadcrumb .breadcrumb-current {
    color: var(--text-secondary);
    font-weight: 500;
}

/* --- Case Detail Layout: Article + TOC --- */
.case-detail-layout {
    display: grid;
    grid-template-columns: 1fr 220px;
    gap: 60px;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 32px;
    align-items: start;
}

/* Case article body */
.case-article {
    max-width: 800px;
    margin: 0;
    padding: 20px 0 80px;
    min-width: 0;
}

.case-article .back-link {
    display: none; /* replaced by breadcrumb */
}

/* Download section */
.download-dark {
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 16px 20px; /* 稍微减小左右 padding */
    margin-bottom: 40px;
    display: flex;
    align-items: center;
    gap: 16px; /* 减小间距 */
    flex-wrap: wrap;
}

/* 覆盖 .case-article h2 的默认样式 */
.case-article .download-dark h2 {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-bright);
    margin: 0;
    border: none;
    padding: 0;
    display: flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
    min-width: fit-content;
    flex-shrink: 0; /* 防止标题被压缩 */
}

.download-content-row {
    display: flex;
    align-items: center;
    gap: 16px; /* 减小间距 */
    flex: 1;
    flex-wrap: nowrap; /* 保持不换行 */
    min-width: 0; /* 允许 flex item 压缩 */
}

.download-dark .download-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: nowrap;
    align-items: center;
    flex-shrink: 0; /* 关键：防止按钮组被压缩换行 */
}

.download-dark .download-tip {
    font-size: 13px;
    color: var(--text-muted);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 6px;
    padding-left: 16px; /* 减小左侧 padding */
    border-left: 1px solid var(--border-subtle);
    height: 24px;
    white-space: nowrap; /* 尝试让提示也不换行，如果溢出再考虑隐藏 */
    overflow: hidden;
    text-overflow: ellipsis;
    flex: 1; /* 占据剩余空间 */
    min-width: 0; /* 允许压缩 */
}

@media (max-width: 1024px) {
    /* 中等屏幕下，允许提示文字换行或者隐藏部分内容 */
    .download-dark .download-tip {
        white-space: normal; /* 允许换行 */
        height: auto;
        line-height: 1.4;
    }
}

@media (max-width: 900px) {
    .download-dark {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
        padding: 20px;
    }
    
    .download-content-row {
        width: 100%;
        flex-wrap: wrap; /* 移动端允许换行 */
    }
    
    .case-article .download-dark h2 {
        font-size: 18px;
        width: 100%;
        border-bottom: 1px solid var(--border-subtle);
        padding-bottom: 12px;
        margin-bottom: 4px;
    }

    .download-dark .download-buttons {
        flex-wrap: wrap; /* 移动端按钮允许换行 */
        width: 100%;
    }
}


@media (max-width: 768px) {
    .download-content-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }
    
    .download-dark .download-tip {
        padding-left: 0;
        border-left: none;
        height: auto;
    }
}

.download-dark .download-tip a {
    color: var(--accent-light);
}

.download-dark .download-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px; /* 减小内边距 */
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
    white-space: nowrap; /* 强制文字不换行 */
    min-width: fit-content; /* 关键：确保按钮不会被压缩小于内容宽度 */
}

.download-dark .download-btn:hover {
    border-color: var(--accent);
    color: var(--accent-light);
    background: var(--accent-glow);
    box-shadow: 0 0 12px rgba(59, 130, 246, 0.4); /* 增加蓝色外发光 */
}

/* 让标题图标带上品牌色电光感 */
.case-article .download-dark h2 i,
.case-steps-bar-title i {
    color: var(--accent-light);
}

.download-dark .download-btn i {
    font-size: 18px;
    color: var(--accent-light);
}

/* Article content typography */
.case-article h1 { font-size: 32px; font-weight: 800; color: var(--text-bright); margin: 40px 0 16px; }
.case-article h2 { font-size: 24px; font-weight: 700; color: var(--text-bright); margin: 60px 0 20px; border-bottom: 1px solid var(--border-subtle); padding-bottom: 12px; }
.case-article h3 { font-size: 20px; font-weight: 600; color: var(--text-bright); margin: 32px 0 12px; }
.case-article h4 { font-size: 17px; font-weight: 600; color: var(--text-primary); margin: 24px 0 8px; }

.case-article p { font-size: 16px; line-height: 1.8; color: var(--text-secondary); margin-bottom: 16px; }
.case-article strong { color: var(--text-bright); }

.case-article ul, .case-article ol {
    margin: 12px 0 16px 24px;
    color: var(--text-secondary);
}
.case-article li { font-size: 15px; line-height: 1.8; margin-bottom: 4px; }

.case-article img {
    max-width: 100%;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-subtle);
    margin: 8px 0;
    cursor: pointer;
}

.case-article figure {
    margin: 20px 0;
    text-align: center;
}

.case-article figcaption {
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 8px;
}

.case-article a { color: var(--accent-light); }
.case-article a:hover { text-decoration: underline; }

.case-article code {
    font-family: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
    font-size: 14px;
    background: var(--dark-surface-3);
    padding: 2px 6px;
    border-radius: 4px;
    color: var(--accent-lighter);
}

.case-article pre {
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 20px 24px;
    overflow-x: auto;
    margin: 16px 0;
}

.case-article pre code {
    background: none;
    padding: 0;
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-primary);
}

/* Case summary box */
.case-summary-dark {
    background: var(--dark-surface-2);
    border-left: 3px solid var(--accent);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    padding: 20px 24px;
    margin-bottom: 32px;
}

.case-summary-dark .summary-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-bright);
    margin-bottom: 8px;
}

.case-summary-dark p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin: 0;
}

/* Image modal (keep for case detail) */
.image-modal {
    position: fixed;
    inset: 0;
    z-index: 9999;
    animation: modalFadeIn 0.2s ease;
}

.image-modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 32px;
}

.image-modal-content {
    position: relative;
    max-width: 90vw;
    max-height: 90vh;
}

.image-modal-content img {
    max-width: 100%;
    max-height: 85vh;
    border-radius: var(--radius-md);
    border: none;
}

.image-modal-close {
    position: absolute;
    top: -12px;
    right: -12px;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: none;
    background: var(--dark-surface-3);
    color: var(--text-bright);
    font-size: 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

@keyframes modalFadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* ========================================
   Case Detail: Table of Contents (sidebar)
   ======================================== */
.case-toc {
    position: sticky;
    top: 100px;
    padding: 24px 0;
    max-height: calc(100vh - 140px);
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--border-subtle) transparent;
}

.case-toc-title {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--text-dim);
    margin-bottom: 16px;
    padding-left: 16px;
}

.case-toc ol {
    list-style: none;
    margin: 0;
    padding: 0;
    border-left: 1px solid var(--border-subtle);
}

.case-toc li {
    margin: 0;
    font-size: 13px;
    line-height: 1.4;
}

.case-toc a {
    display: block;
    padding: 6px 16px;
    color: var(--text-muted);
    font-weight: 500;
    transition: color 0.2s, border-color 0.2s, background 0.2s;
    border-left: 2px solid transparent;
    margin-left: -1px;
}

.case-toc a:hover {
    color: var(--text-primary);
    text-decoration: none;
}

.case-toc a.toc-active {
    color: var(--accent-light);
    border-left-color: var(--accent);
    background: linear-gradient(90deg, rgba(59, 130, 246, 0.06), transparent);
}

.case-toc .toc-h2 {
    padding-left: 28px;
    font-size: 12px;
}

.case-toc .toc-h3 {
    padding-left: 40px;
    font-size: 12px;
    color: var(--text-dim);
}

/* ========================================
   Case Detail: Step Progress Bar
   ======================================== */
.case-steps-bar {
    background: var(--dark-surface-2);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 24px 28px;
    margin-bottom: 60px; /* 增加底部间距，让"问题描述"有呼吸感 */
    overflow-x: auto;
}

/* 升级解决步骤标题样式，与资源下载保持一致 */
.case-steps-bar-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-bright);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.case-steps-list {
    display: flex;
    align-items: center;
    gap: 0;
    min-width: max-content;
}

.case-step-item {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.case-step-dot {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--dark-surface-3);
    border: 2px solid var(--border-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 700;
    color: var(--text-muted);
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.case-step-name {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    transition: color 0.3s;
    max-width: 140px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.case-step-connector {
    width: 32px;
    height: 2px;
    background: var(--border-subtle);
    margin: 0 4px;
    flex-shrink: 0;
    transition: background 0.3s;
}

/* Step active state */
.case-step-item.step-active .case-step-dot {
    background: var(--accent);
    border-color: var(--accent);
    color: white;
    box-shadow: 0 0 16px rgba(59, 130, 246, 0.3);
}

.case-step-item.step-active .case-step-name {
    color: var(--accent-light);
}

/* Step completed (passed) state */
.case-step-item.step-passed .case-step-dot {
    background: var(--accent-glow);
    border-color: var(--accent);
    color: var(--accent-light);
}

.case-step-item.step-passed .case-step-name {
    color: var(--text-secondary);
}

.case-step-connector.connector-passed {
    background: var(--accent);
}

.case-step-item:hover .case-step-dot {
    border-color: var(--accent-light);
}

.case-step-item:hover .case-step-name {
    color: var(--text-primary);
}

/* ========================================
   Case Detail: Related Cases
   ======================================== */
.related-cases-dark {
    padding: 80px 0;
    border-top: 1px solid var(--border-subtle);
    position: relative;
    z-index: 1;
}

.related-cases-header {
    text-align: center;
    margin-bottom: 48px;
}

.related-cases-header .section-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2.5px;
    color: var(--accent-light);
    margin-bottom: 12px;
}

.related-cases-header h2 {
    font-size: clamp(24px, 3vw, 32px);
    font-weight: 800;
    color: var(--text-bright);
    letter-spacing: -0.5px;
    margin: 0;
    border: none;
    padding: 0;
}

.related-cases-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.related-cases-grid .ag-case-card {
    background: var(--dark-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: transform 0.5s cubic-bezier(0.16, 1, 0.3, 1),
                border-color 0.3s,
                box-shadow 0.5s;
    text-decoration: none;
    display: block;
}

.related-cases-grid .ag-case-card:hover {
    transform: translateY(-6px);
    border-color: var(--border-accent);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.35);
    text-decoration: none;
}

.related-cases-grid .ag-case-img {
    width: 100%;
    height: 160px;
    object-fit: cover;
    display: block;
    filter: brightness(0.85);
    transition: filter 0.4s;
    border: none;
    border-radius: 0;
    margin: 0;
    cursor: default;
}

.related-cases-grid .ag-case-card:hover .ag-case-img {
    filter: brightness(1);
}

.related-cases-grid .ag-case-body {
    padding: 20px 24px;
}

.related-cases-grid .ag-case-cat {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--accent-light);
    margin-bottom: 6px;
}

.related-cases-grid .ag-case-name {
    font-size: 15px;
    font-weight: 700;
    color: var(--text-bright);
    margin-bottom: 4px;
}

.related-cases-grid .ag-case-desc {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ========================================
   Case Detail: Back to Top Button
   ======================================== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--dark-surface-3);
    border: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 100;
    opacity: 0;
    transform: translateY(20px);
    pointer-events: none;
    transition: opacity 0.3s, transform 0.3s, border-color 0.2s, color 0.2s, background 0.2s;
}

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

.back-to-top:hover {
    border-color: var(--accent);
    color: var(--accent-light);
    background: var(--dark-surface-2);
    box-shadow: 0 0 20px rgba(59, 130, 246, 0.15);
}

/* ========================================
   Case Detail: Responsive Overrides
   ======================================== */
@media (max-width: 1024px) {
    .case-detail-layout {
        grid-template-columns: 1fr;
        gap: 0;
        padding: 0 32px;
    }

    .case-toc {
        display: none;
    }

    .case-article {
        max-width: 800px;
        margin: 0 auto;
    }

    .related-cases-grid {
        grid-template-columns: 1fr;
        max-width: 480px;
        margin: 0 auto;
    }
}

@media (max-width: 768px) {
    .case-detail-hero {
        padding: 120px 0 48px;
    }

    .case-detail-layout {
        padding: 0 20px;
    }

    .case-steps-bar {
        padding: 16px 20px;
    }

    .case-step-name {
        display: none;
    }

    .case-step-connector {
        width: 20px;
    }

    .case-breadcrumb ol {
        font-size: 12px;
    }

    .back-to-top {
        bottom: 20px;
        right: 20px;
    }

    .related-cases-dark {
        padding: 60px 0;
    }
}