:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f1f5f9;
    --text-primary: #0a0a1a;
    --text-secondary: #2d3a4a;
    --accent: #3b82f6;
    --accent-glow: #60a5fa;
    --accent-gradient: linear-gradient(135deg, #3b82f6, #8b5cf6, #d946ef);
    --card-bg: #ffffff;
    --border: rgba(0, 0, 0, 0.08);
    --shadow: 0 20px 35px -12px rgba(0, 0, 0, 0.1);
    --glass-bg: rgba(255, 255, 255, 0.75);
    --code-bg: #0f172a;
    --code-color: #e2e8f0;
}

[data-theme="dark"] {
    --bg-primary: #050510;
    --bg-secondary: #0a0a1a;
    --text-primary: #f0f3fa;
    --text-secondary: #a0b0c0;
    --accent: #60a5fa;
    --accent-glow: #a78bfa;
    --card-bg: #111122;
    --border: rgba(255, 255, 255, 0.08);
    --shadow: 0 20px 35px -12px rgba(0, 0, 0, 0.5);
    --glass-bg: rgba(10, 10, 26, 0.7);
    --code-bg: #050510;
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    transition: background-color 0.4s cubic-bezier(0.2, 0.9, 0.4, 1.1), color 0.3s;
    scroll-behavior: smooth;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 28px;
}

.glass-nav {
    position: sticky;
    top: 0;
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    z-index: 100;
    padding: 18px 0;
}

.nav-container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

.logo {
    font-size: 1.6rem;
    font-weight: 800;
    background: var(--accent-gradient);
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
    letter-spacing: -0.5px;
}

.logo i {
    margin-right: 8px;
    background: none;
    color: var(--accent);
}

.accent {
    background: none;
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: 32px;
    flex-wrap: wrap;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 6px;
}

.nav-links a i {
    font-size: 0.9rem;
}

.nav-links a:hover {
    color: var(--accent);
    transform: translateY(-2px);
}

.student-info {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--accent-gradient);
    padding: 8px 16px;
    border-radius: 40px;
    font-size: 0.85rem;
    font-weight: 500;
    color: white;
    backdrop-filter: blur(4px);
    transition: transform 0.2s;
}

.student-info:hover {
    transform: scale(1.05);
}

.student-info i {
    font-size: 1rem;
}

.theme-switch-wrapper {
    position: fixed;
    bottom: 28px;
    right: 28px;
    z-index: 1000;
}

.theme-toggle {
    width: 56px;
    height: 56px;
    border-radius: 30px;
    background: var(--card-bg);
    border: 1px solid var(--border);
    font-size: 1.6rem;
    cursor: pointer;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    transform: scale(1.12) rotate(8deg);
    border-color: var(--accent);
}

.particles-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 40%, rgba(59,130,246,0.08) 0%, transparent 50%),
                repeating-linear-gradient(45deg, transparent, transparent 2px, rgba(139,92,246,0.03) 2px, rgba(139,92,246,0.03) 6px);
    pointer-events: none;
}

section {
    padding: 110px 0;
    position: relative;
    overflow-x: hidden;
}

.center-section {
    text-align: center;
}

.hero {
    min-height: 90vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.hero-content {
    max-width: 850px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    padding: 8px 20px;
    border-radius: 60px;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 28px;
    border: 1px solid var(--border);
}

.hero-content h1 {
    font-size: clamp(2.6rem, 8vw, 5.2rem);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 28px;
}

.gradient-text {
    background: var(--accent-gradient);
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
}

.hero-content p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    max-width: 650px;
    margin: 0 auto 40px;
}

.hero-buttons {
    display: flex;
    gap: 18px;
    justify-content: center;
    flex-wrap: wrap;
}

.cta-button {
    border: none;
    padding: 14px 32px;
    border-radius: 48px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.25s ease;
    display: inline-flex;
    align-items: center;
    gap: 10px;
}

.cta-button.primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 8px 20px rgba(59,130,246,0.3);
}

.cta-button.primary:hover {
    transform: translateY(-4px);
    box-shadow: 0 18px 30px rgba(59,130,246,0.4);
}

.cta-button.secondary {
    background: transparent;
    border: 1.5px solid var(--border);
    color: var(--text-primary);
}

.cta-button.secondary:hover {
    border-color: var(--accent);
    transform: translateY(-3px);
}

.cta-button.large {
    padding: 16px 40px;
    font-size: 1.15rem;
}

.split-layout {
    display: flex;
    align-items: center;
    gap: 64px;
    flex-wrap: wrap;
}

.split-layout.reverse {
    flex-direction: row-reverse;
}

.text-block, .image-block {
    flex: 1;
    min-width: 280px;
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--accent);
    color: white;
    padding: 6px 16px;
    border-radius: 40px;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 24px;
}

.text-block h2 {
    font-size: clamp(1.9rem, 5vw, 2.6rem);
    margin-bottom: 20px;
    line-height: 1.3;
}

.text-block p {
    color: var(--text-secondary);
    margin-bottom: 28px;
}

.feature-grid {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    margin-top: 28px;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--bg-secondary);
    padding: 8px 18px;
    border-radius: 50px;
    font-size: 0.9rem;
}

.feature-item i {
    color: var(--accent);
    font-size: 1.2rem;
}

.floating-card {
    background: var(--card-bg);
    border-radius: 32px;
    padding: 40px 32px;
    text-align: center;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: transform 0.3s;
}

.floating-card:hover {
    transform: translateY(-8px);
}

.floating-card i {
    font-size: 3rem;
    color: var(--accent);
    margin-bottom: 20px;
}

.code-card {
    background: var(--code-bg);
    border-radius: 28px;
    padding: 28px;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.code-card:hover {
    transform: scale(1.02);
    box-shadow: 0 25px 40px -12px rgba(0,0,0,0.3);
}

.code-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
    color: #94a3b8;
    font-weight: 500;
}

.code-card pre {
    color: var(--code-color);
    font-family: 'Fira Code', monospace;
    font-size: 0.85rem;
    overflow-x: auto;
}

.keyword { color: #c084fc; }
.function { color: #60a5fa; }
.string { color: #4ade80; }

.stats-mini {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
    margin-top: 20px;
}

.stats-mini div {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
}

.alt-bg {
    background: var(--bg-secondary);
}

.abstraction-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 32px;
    margin: 60px 0 50px;
}

.abstraction-card {
    background: var(--card-bg);
    border-radius: 32px;
    padding: 36px 24px;
    text-align: center;
    transition: all 0.3s;
    border: 1px solid var(--border);
}

.hover-scale:hover {
    transform: scale(1.05) translateY(-6px);
    border-color: var(--accent);
    box-shadow: var(--shadow);
}

.abstraction-card i {
    font-size: 2.6rem;
    color: var(--accent);
    margin-bottom: 20px;
}

.abstract-quote {
    background: var(--accent-gradient);
    padding: 48px 32px;
    border-radius: 48px;
    text-align: center;
    color: white;
    margin-top: 40px;
}

.abstract-quote i {
    font-size: 2.2rem;
    opacity: 0.8;
    margin-bottom: 16px;
    display: inline-block;
}

.abstract-quote p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto;
    font-weight: 500;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: clamp(1.9rem, 5vw, 2.6rem);
    margin-top: 12px;
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 32px;
}

.card {
    background: var(--card-bg);
    border-radius: 32px;
    padding: 36px 24px;
    text-align: center;
    transition: all 0.3s;
    border: 1px solid var(--border);
}

.hover-lift:hover {
    transform: translateY(-12px);
    box-shadow: var(--shadow);
    border-color: var(--accent);
}

.card-icon {
    font-size: 2.8rem;
    margin-bottom: 20px;
    color: var(--accent);
}

.card h3 {
    margin-bottom: 12px;
}

.card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 20px;
}

.card-tag {
    display: inline-block;
    background: var(--bg-secondary);
    padding: 4px 12px;
    border-radius: 30px;
    font-size: 0.7rem;
    font-weight: 600;
}

.cta-section {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, transparent 100%);
    border-radius: 60px;
    margin: 30px 28px;
    padding: 80px 24px;
}

.cta-container {
    max-width: 750px;
    margin: 0 auto;
    text-align: center;
    position: relative;
}

.floating-icon {
    font-size: 3rem;
    color: var(--accent);
    margin-bottom: 20px;
    opacity: 0.8;
}

.trust-badges {
    display: flex;
    justify-content: center;
    gap: 28px;
    margin-top: 32px;
    flex-wrap: wrap;
}

.trust-badges span {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    opacity: 0.8;
}

footer {
    border-top: 1px solid var(--border);
    padding: 50px 0 40px;
}

.footer-content {
    text-align: center;
}

.footer-logo {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.social-icons {
    display: flex;
    justify-content: center;
    gap: 28px;
    margin-top: 28px;
}

.social-icons i {
    font-size: 1.4rem;
    cursor: pointer;
    transition: transform 0.2s, color 0.2s;
}

.social-icons i:hover {
    color: var(--accent);
    transform: translateY(-3px);
}

@keyframes fadeUp {
    from { opacity: 0; transform: translateY(40px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideRight {
    from { opacity: 0; transform: translateX(-50px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes slideLeft {
    from { opacity: 0; transform: translateX(50px); }
    to { opacity: 1; transform: translateX(0); }
}

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

@keyframes gentlePulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.02); }
}

.animate-fade-up {
    animation: fadeUp 0.9s cubic-bezier(0.2, 0.9, 0.4, 1.1) forwards;
}

.animate-slide-right {
    animation: slideRight 0.8s ease forwards;
}

.animate-slide-left {
    animation: slideLeft 0.8s ease forwards;
}

.animate-scale {
    animation: scaleIn 0.7s ease forwards;
}

.animate-pulse-gentle {
    animation: gentlePulse 3s infinite;
}

@media (max-width: 900px) {
    .split-layout, .split-layout.reverse {
        flex-direction: column;
        text-align: center;
        gap: 48px;
    }
    .feature-grid, .stats-mini {
        justify-content: center;
    }
    .nav-links {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    section {
        padding: 70px 0;
    }
    .nav-container {
        flex-direction: column;
        gap: 12px;
    }
    .student-info {
        font-size: 0.75rem;
        padding: 6px 12px;
    }
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    .cta-section {
        margin: 20px 16px;
        padding: 50px 20px;
    }
}

@media (max-width: 480px) {
    .nav-links {
        gap: 12px;
        flex-wrap: wrap;
        justify-content: center;
    }
    .student-info {
        margin-top: 4px;
    }
}