:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: rgba(20, 20, 30, 0.8);
    --text-primary: #ffffff;
    --text-secondary: #8b8b9e;
    --accent: #00d4ff;
    --accent-secondary: #7b61ff;
    --gradient-1: linear-gradient(135deg, #00d4ff 0%, #7b61ff 100%);
    --gradient-2: linear-gradient(135deg, #7b61ff 0%, #00d4ff 100%);
    --glow: 0 0 40px rgba(0, 212, 255, 0.3);
    --radius: 20px;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow-x: hidden;
    line-height: 1.6;
}

/* Navigation */
.nav-container {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 0 40px;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav-container.scrolled {
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

.nav-bar {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
    position: relative;
}

.logo::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--gradient-1);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.logo:hover::after { transform: scaleX(1); }

.nav-links {
    display: flex;
    gap: 40px;
    align-items: center;
}

.nav-item {
    position: relative;
}

.nav-links > a, .nav-item > a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    transition: all 0.3s ease;
    padding: 8px 0;
    position: relative;
}

.nav-links > a:hover, .nav-item > a:hover {
    color: var(--accent);
}

.nav-links > a::after, .nav-item > a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-1);
    transition: width 0.3s ease;
}

.nav-links > a:hover::after, .nav-item > a:hover::after {
    width: 100%;
}

.dropdown {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(10px);
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border-radius: var(--radius);
    padding: 20px;
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, transform 0.2s ease;
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: var(--shadow);
}

.nav-item:hover .dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.dropdown a {
    display: block;
    padding: 12px 16px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    border-radius: 8px;
    transition: color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
}

.dropdown a:hover {
    background: rgba(0, 212, 255, 0.1);
    color: var(--accent);
    transform: translateX(4px);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 120px 40px 80px;
    position: relative;
    z-index: 1;
}

.hero-content {
    text-align: center;
    max-width: 1000px;
    margin-bottom: 60px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 20px;
    background: rgba(0, 212, 255, 0.1);
    border: 1px solid rgba(0, 212, 255, 0.3);
    border-radius: 100px;
    font-size: 13px;
    color: var(--accent);
    margin-bottom: 30px;
    animation: fadeInUp 0.8s ease forwards;
}

.hero-badge::before {
    content: '';
    width: 8px;
    height: 8px;
    background: var(--accent);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(1.2); }
}

.hero-title {
    font-size: clamp(52px, 9vw, 108px);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -3px;
    margin-bottom: 20px;
    animation: fadeInUp 0.8s ease 0.1s forwards;
    opacity: 0;
}

.hero-title .gradient-text {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(20px, 2.8vw, 28px);
    font-weight: 400;
    color: var(--text-secondary);
    margin-top: 20px;
    margin-bottom: 50px;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 0.8s ease-out 0.2s forwards;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Showcase Grid */
.showcase {
    display: grid;
    grid-template-columns: 1fr 1.8fr 1fr;
    grid-template-rows: 1fr 1fr;
    gap: 20px;
    width: 100%;
    max-width: 1400px;
    height: 500px;
    animation: fadeInUp 0.8s ease 0.3s forwards;
    opacity: 0;
}

.side-column {
    display: flex;
    flex-direction: column;
    gap: 20px;
    height: 100%;
}

.card {
    position: relative;
    border-radius: var(--radius);
    overflow: hidden;
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    height: 100%;
}

.card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-1);
    opacity: 0;
    transition: opacity 0.5s ease;
    z-index: 1;
}

.card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: var(--glow);
    border-color: rgba(0, 212, 255, 0.3);
}

.card:hover::before { opacity: 0.05; }

.card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.card:hover img { transform: scale(1.08); }

.card-small {
    flex: 1;
}

.card-main {
    grid-column: 2;
    grid-row: 1 / 3;
    height: 100%;
}

.card-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 30px;
    background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
    z-index: 2;
    transform: translateY(20px);
    opacity: 0;
    transition: all 0.4s ease;
}

.card:hover .card-overlay {
    transform: translateY(0);
    opacity: 1;
}

.card-overlay h4 {
    font-size: 18px;
    margin-bottom: 8px;
}

.card-overlay p {
    font-size: 13px;
    color: var(--text-secondary);
}

/* Sections */
section {
    position: relative;
    z-index: 1;
    padding: 120px 40px;
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(123, 97, 255, 0.1);
    border: 1px solid rgba(123, 97, 255, 0.3);
    border-radius: 100px;
    font-size: 13px;
    color: var(--accent-secondary);
    margin-bottom: 20px;
}

.section-title {
    font-size: clamp(42px, 5.5vw, 64px);
    font-weight: 800;
    margin-bottom: 24px;
    letter-spacing: -1.5px;
}

.section-desc {
    font-size: 20px;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto;
    line-height: 1.8;
}

/* Tech Cards */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
    max-width: 1400px;
    margin: 0 auto;
}

.tech-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius);
    padding: 40px;
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
}

.tech-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-1);
    transform: scaleX(0);
    transition: transform 0.4s ease;
}

.tech-card:hover {
    transform: translateY(-8px);
    border-color: rgba(0, 212, 255, 0.2);
    box-shadow: var(--shadow);
}

.tech-card:hover::before { transform: scaleX(1); }

.tech-card h3 {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 18px;
    position: relative;
}

.tech-card p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.8;
}

.tech-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-1);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
    font-size: 28px;
}

.tech-icon svg {
    width: 30px;
    height: 30px;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
}

/* Category Cards */
.category-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius);
    padding: 60px;
    display: flex;
    align-items: center;
    gap: 60px;
    margin-bottom: 40px;
    transition: all 0.4s ease;
    text-decoration: none;
    color: inherit;
}

.category-card:hover {
    transform: translateY(-4px);
    border-color: rgba(0, 212, 255, 0.2);
    box-shadow: var(--shadow);
}

.category-card.reverse { flex-direction: row-reverse; }

.category-img {
    flex: 1;
    min-width: 400px;
    height: 350px;
    border-radius: 16px;
    overflow: hidden;
    position: relative;
}

.category-img::after {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-1);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.category-card:hover .category-img::after { opacity: 0.1; }

.category-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.category-card:hover .category-img img { transform: scale(1.05); }

.category-content { flex: 1; }

.category-content h3 {
    font-size: 34px;
    font-weight: 800;
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.category-content p {
    color: var(--text-secondary);
    font-size: 18px;
    line-height: 1.9;
    margin-bottom: 30px;
}

.feature-list {
    list-style: none;
}

.feature-list li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 0;
    color: var(--text-secondary);
    font-size: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.feature-list li:last-child { border-bottom: none; }

.feature-list svg {
    flex-shrink: 0;
    stroke: var(--accent);
}

/* Timeline */
.timeline {
    max-width: 1000px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 100%;
    background: linear-gradient(to bottom, var(--accent), var(--accent-secondary));
}

.timeline-item {
    display: flex;
    justify-content: center;
    padding: 40px 0;
    position: relative;
}

.timeline-dot {
    width: 20px;
    height: 20px;
    background: var(--accent);
    border-radius: 50%;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    box-shadow: 0 0 20px var(--accent);
}

.timeline-content {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius);
    padding: 30px 40px;
    width: 45%;
    transition: all 0.4s ease;
}

.timeline-content:hover {
    transform: scale(1.02);
    border-color: rgba(0, 212, 255, 0.2);
}

.timeline-year {
    font-size: 14px;
    color: var(--accent);
    margin-bottom: 8px;
}

.timeline-content h4 {
    font-size: 18px;
    margin-bottom: 8px;
}

.timeline-content p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* Footer */
footer {
    position: relative;
    z-index: 1;
    background: var(--bg-secondary);
    padding: 60px 40px;
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-bottom: 30px;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s ease;
}

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

.footer-copy {
    color: var(--text-secondary);
    font-size: 13px;
}

/* Scroll Animations */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* Mobile Menu Button */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 6px;
    cursor: pointer;
    padding: 10px;
}

.menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all 0.3s ease;
}

/* ============ 响应式适配 ============ */

/* 平板横屏 / 小笔记本 (≤1024px) */
@media (max-width: 1024px) {
    .showcase {
        grid-template-columns: 1fr 1fr;
        grid-template-rows: auto auto auto;
        height: auto;
    }
    .card-main {
        grid-column: 1 / 3;
        grid-row: auto;
        height: 300px;
    }
    .side-column {
        flex-direction: row;
        height: auto;
    }
    .card-small { height: 150px; }

    section { padding: 100px 30px; }
    .hero { padding: 100px 30px 60px; }
    .tech-grid { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; }
    .category-card, .category-card.reverse {
        padding: 40px;
        gap: 40px;
    }
    .category-img { min-width: 300px; height: 300px; }
    .category-content h3 { font-size: 28px; }
    .category-content p { font-size: 16px; }
}

/* 平板竖屏 (≤768px) */
@media (max-width: 768px) {
    .nav-container { padding: 0 16px; }
    .nav-bar { padding: 14px 0; }
    .logo { font-size: 20px; }

    .nav-links {
        display: none;
        position: fixed;
        top: 70px;
        left: 16px;
        right: 16px;
        background: rgba(18, 18, 26, 0.98);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 24px;
        gap: 8px;
        border-radius: var(--radius);
        border: 1px solid rgba(255, 255, 255, 0.1);
        box-shadow: var(--shadow);
        z-index: 1001;
    }
    .nav-links.active { display: flex; }
    .nav-links > a, .nav-item > a {
        padding: 14px 16px;
        font-size: 16px;
        border-radius: 10px;
    }
    .nav-links > a:hover, .nav-item > a:hover {
        background: rgba(0, 212, 255, 0.08);
    }
    .menu-toggle { display: flex; }

    /* 移动端下拉菜单 */
    .dropdown {
        position: static;
        transform: none;
        opacity: 1;
        visibility: visible;
        background: transparent;
        border: none;
        padding: 0 0 0 16px;
        min-width: auto;
        box-shadow: none;
        display: none;
    }
    .nav-item:hover .dropdown,
    .nav-item.active .dropdown { display: block; }
    .dropdown a { padding: 10px 16px; font-size: 14px; }

    .hero { padding: 100px 20px 50px; min-height: auto; }
    .hero-content { margin-bottom: 40px; }
    .hero-badge { font-size: 12px; padding: 6px 16px; }
    .hero-subtitle { font-size: 16px; margin-bottom: 30px; }

    .showcase {
        grid-template-columns: 1fr;
        height: auto;
        gap: 12px;
    }
    .card-main {
        grid-column: 1;
        height: 250px;
    }
    .side-column {
        flex-direction: row;
        height: auto;
    }
    .card-small { height: 130px; }

    /* 移动端卡片遮罩始终可见 */
    .card-overlay {
        transform: translateY(0);
        opacity: 1;
        padding: 20px;
    }
    .card-overlay h4 { font-size: 15px; }
    .card-overlay p { font-size: 12px; }

    /* 轮播按钮移动端始终可见 */
    .carousel-btn { opacity: 0.7; padding: 12px 10px; font-size: 14px; }

    section { padding: 60px 16px; }
    .section-header { margin-bottom: 50px; }
    .section-tag { font-size: 12px; }
    .section-desc { font-size: 16px; }

    .tech-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    .tech-card { padding: 28px; }
    .tech-card h3 { font-size: 22px; }
    .tech-card p { font-size: 14px; }
    .tech-icon { width: 48px; height: 48px; font-size: 22px; margin-bottom: 16px; }

    .category-card,
    .category-card.reverse {
        flex-direction: column;
        padding: 24px;
        gap: 24px;
        margin-bottom: 24px;
    }
    .category-img {
        min-width: 100%;
        height: 220px;
    }
    .category-content h3 { font-size: 26px; }
    .category-content p { font-size: 15px; }
    .feature-list li { font-size: 14px; padding: 10px 0; }

    .timeline::before { left: 18px; }
    .timeline-item { justify-content: flex-start; padding: 24px 0 24px 44px; }
    .timeline-dot { left: 18px; width: 14px; height: 14px; }
    .timeline-content { width: 100%; padding: 20px 24px; }
    .timeline-content h4 { font-size: 16px; }
    .timeline-content p { font-size: 13px; }

    footer { padding: 40px 16px; }
    .footer-links { gap: 20px; flex-wrap: wrap; }
    .footer-links a { font-size: 13px; }

    .glow-line { margin: 0 16px; }
}

/* 小屏手机 (≤480px) */
@media (max-width: 480px) {
    .nav-container { padding: 0 10px; }
    .nav-bar { padding: 10px 0; }
    .logo { font-size: 18px; }
    .nav-links { left: 10px; right: 10px; top: 60px; }

    .hero { padding: 80px 14px 40px; }
    .hero-badge { font-size: 11px; padding: 5px 14px; margin-bottom: 20px; }
    .hero-subtitle { font-size: 14px; margin-bottom: 24px; }

    .showcase { gap: 10px; }
    .card-main { height: 200px; }
    .side-column { flex-direction: column; }
    .card-small { height: 120px; }

    section { padding: 50px 12px; }
    .section-header { margin-bottom: 36px; }
    .section-desc { font-size: 14px; line-height: 1.7; }

    .tech-card { padding: 22px; }
    .tech-card h3 { font-size: 20px; }

    .category-card,
    .category-card.reverse { padding: 18px; gap: 18px; }
    .category-img { height: 180px; }
    .category-content h3 { font-size: 22px; margin-bottom: 12px; }
    .category-content p { font-size: 14px; line-height: 1.7; }

    .timeline-item { padding-left: 38px; }
    .timeline-content { padding: 16px 18px; }

    footer { padding: 30px 12px; }
    .footer-links { gap: 14px; }
    .footer-links a { font-size: 12px; }
    .footer-copy { font-size: 11px; }

    .carousel-btn { padding: 8px 8px; font-size: 12px; }
    .dot { width: 8px; height: 8px; }
}

/* Floating Elements */
.floating {
    animation: floating 3s ease-in-out infinite;
}

@keyframes floating {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

/* Glow Line */
.glow-line {
    height: 1px;
    background: var(--gradient-1);
    opacity: 0.3;
}

/* Image Carousel */
.image-carousel {
    position: relative;
    width: 100%;
    height: 100%;
}

.carousel-container {
    position: relative;
    width: 100%;
    height: 100%;
}

.carousel-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
}

.carousel-img.active {
    opacity: 1;
}

.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 0, 0, 0.5);
    color: white;
    border: none;
    padding: 16px 12px;
    cursor: pointer;
    font-size: 18px;
    border-radius: 8px;
    transition: all 0.3s ease;
    z-index: 10;
    opacity: 0;
}

.image-carousel:hover .carousel-btn {
    opacity: 1;
}

.carousel-btn:hover {
    background: rgba(0, 212, 255, 0.8);
    transform: translateY(-50%) scale(1.1);
}

.carousel-btn.prev { left: 15px; }
.carousel-btn.next { right: 15px; }

.carousel-dots {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
    z-index: 10;
}

.dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.4);
    cursor: pointer;
    transition: all 0.3s ease;
}

.dot:hover { background: rgba(255, 255, 255, 0.7); }

.dot.active {
    background: var(--accent);
    box-shadow: 0 0 10px var(--accent);
}

/* Page Transition */
.page-transition {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-primary);
    z-index: 9999;
    pointer-events: none;
    opacity: 1;
    transition: opacity 0.5s ease-out;
}

.page-transition.hidden {
    opacity: 0;
}

.page-content {
    opacity: 0;
    transform: translateY(20px);
    animation: pageIn 0.6s ease-out 0.3s forwards;
}

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

/* Scroll Reveal Animation */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* Teaching homepage: clear entrances and a continuous learning route */
:root { --text-secondary: #a8afbf; }
body { font-family: "Segoe UI", "Microsoft YaHei", system-ui, sans-serif; }
.logo { text-decoration: none; }
.hero { min-height: auto; padding-top: 136px; padding-bottom: 64px; }
.hero-content { width: 100%; max-width: 1000px; margin-bottom: 48px; }
.hero-title { font-size: clamp(38px, 5.8vw, 76px); line-height: 1.2; letter-spacing: -.045em; opacity: 1; animation: none; }
.hero-badge { animation: none; }
.hero-badge::before { animation: none; }
.hero-subtitle { font-size: clamp(16px, 1.6vw, 22px); line-height: 1.85; margin: 22px auto 28px; opacity: 1; transform: none; animation: none; }
.hero-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 14px; }
.home-action {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    gap: 24px;
    min-height: 50px;
    padding: 12px 24px;
    border: 1px solid rgba(0, 212, 255, .4);
    border-radius: 10px;
    background: #12121a;
    color: #fff;
    font-weight: 600;
    text-decoration: none;
    transition: border-color .2s ease, transform .2s ease;
}
.home-action.primary { background: #00d4ff; color: #0a0a0f; }
.home-action:hover { transform: translateY(-2px); border-color: #00d4ff; }
.hero-note { margin-top: 18px; font-size: 12px; color: var(--text-secondary); letter-spacing: .06em; }
.showcase { max-width: 1200px; height: 380px; opacity: 1; animation: none; }
.card { cursor: default; }
.card-overlay { pointer-events: none; transform: none; opacity: 1; padding: 20px; }
.card-main .card-overlay { padding: 24px 26px 48px; }
.card:hover { transform: none; }
.card:hover img { transform: none; }
.card-overlay p { color: #d2d7e1; }
.nav-disclosure {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 44px;
    padding: 8px 0;
    border: 0;
    background: transparent;
    color: var(--text-secondary);
    font-weight: 500;
    line-height: 1.6;
    font-family: inherit;
    font-size: 15px;
    cursor: pointer;
}
.nav-disclosure:hover, .nav-disclosure[aria-expanded="true"] { color: var(--accent); }
.nav-disclosure span { transition: transform .2s ease; }
.nav-disclosure[aria-expanded="true"] span { transform: rotate(180deg); }
.nav-item:hover .dropdown { opacity: 0; visibility: hidden; transform: translateX(-50%) translateY(10px); }
.nav-item.active .dropdown { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
html:not(.js) .nav-item:hover .dropdown,
html:not(.js) .nav-item:focus-within .dropdown { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
.carousel-btn { display: grid; place-items: center; min-width: 44px; min-height: 44px; padding: 8px; opacity: 1; }
.carousel-dots { bottom: 14px; gap: 2px; }
.dot { position: relative; width: 32px; height: 28px; border: 0; border-radius: 8px; background: transparent; }
.dot::after { content: ""; position: absolute; width: 8px; height: 8px; border-radius: 50%; background: #7e8896; top: 10px; left: 12px; }
.dot:hover, .dot.active { background: transparent; box-shadow: none; }
.dot.active::after { background: #00d4ff; }
.carousel-pause {
    position: absolute;
    top: 14px;
    right: 14px;
    z-index: 10;
    min-height: 36px;
    padding: 6px 12px;
    border: 1px solid rgba(255,255,255,.3);
    border-radius: 8px;
    background: rgba(10,10,15,.85);
    color: #fff;
    font-size: 12px;
    line-height: 1.5;
    font-family: inherit;
    cursor: pointer;
}
.carousel-pause:disabled { cursor: default; }
.learning-step { display: block; margin: 16px 0 10px; color: #00d4ff; font-size: 12px; letter-spacing: .04em; }
.learning-link { display: inline-flex; gap: 18px; margin-top: 22px; color: #dce3ee; font-size: 14px; }
.tech-card h3 { font-size: clamp(22px, 2.2vw, 28px); }
.tech-card p { line-height: 1.85; }
.timeline-sources { max-width: 900px; margin: -60px auto 70px; padding: 0 30px; color: var(--text-secondary); font-size: 12px; position: relative; z-index: 1; }
.timeline-sources a { color: #a8dcec; text-underline-offset: 4px; }
@media (max-width: 1024px) {
    .nav-links { gap: 24px; }
    .showcase { height: auto; }
}
@media (max-width: 768px) {
    .hero { padding: 102px 20px 40px; }
    .hero-content { margin-bottom: 32px; }
    .hero-title { font-size: clamp(36px, 7vw, 58px); }
    .showcase .card-main { grid-row: 1; height: 300px; }
    .nav-item { width: 100%; }
    .nav-links { align-items: stretch; padding: 16px; }
    .nav-disclosure { justify-content: space-between; width: 100%; padding: 12px 16px; font-size: 16px; }
    .nav-item:hover .dropdown { display: none; }
    .nav-item .dropdown { opacity: 1; visibility: visible; transform: none; }
    .nav-item.active .dropdown { display: block; transform: none; }
    html:not(.js) .nav-item .dropdown { display: block; transform: none; }
    .carousel-btn { min-width: 44px; min-height: 44px; }
    .carousel-pause { min-height: 44px; }
    .dot { width: 44px; height: 32px; }
    .dot::after { top: 12px; left: 18px; }
    .card-main .card-overlay { padding-bottom: 52px; }
    .timeline-sources { margin-top: -30px; margin-bottom: 40px; }
}
@media (max-width: 480px) {
    .hero { padding-inline: 16px; }
    .hero-title { font-size: 38px; }
    .hero-subtitle { font-size: 15px; }
    .hero-subtitle br { display: none; }
    .hero-actions { gap: 10px; }
    .home-action { width: 100%; max-width: 340px; }
    .showcase .card-main { height: 250px; }
    .showcase .side-column { flex-direction: row; }
    .card-small { min-width: 0; }
    .card-overlay { padding: 12px; }
    .card-small .card-overlay p { display: none; }
    .lab-preview { padding: 24px; }
}
.showcase { grid-template-rows: 380px; align-items: stretch; }
.showcase .side-column { min-height: 0; }
.showcase .card-small { min-height: 0; }
.showcase .card-main { grid-row: auto; grid-column: 2; min-height: 0; }
@media (max-width: 1024px) {
    .showcase { grid-template-columns: 1fr 1fr; grid-template-rows: auto auto; }
    .showcase .card-main { grid-column: 1 / -1; grid-row: 1; height: 320px; }
    .showcase .side-column { height: 150px; }
}
@media (max-width: 768px) {
    .showcase { grid-template-columns: 1fr; grid-template-rows: auto; }
    .showcase .card-main { grid-column: 1; height: 300px; }
    .showcase .side-column { height: 130px; }
}
@media (max-width: 480px) {
    .showcase .card-main { height: 250px; }
    .showcase .side-column { height: 120px; }
}