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

:root {
    --bg: #ffffff;
    --bg-alt: #f8fafc;
    --text: #0f172a;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --accent: #4f46e5;
    --accent-light: #e0e7ff;
    --success: #10b981;
    --card: #ffffff;

    --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
    --shadow-md: 0 6px 20px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    font-size: 17px;
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
    color: var(--text);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

/* === LAYOUT === */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* === HEADER === */
header {
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border);
    background: rgba(255,255,255,0.8);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 10;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-weight: 700;
    font-size: 1.15rem;
    color: var(--text);
    text-decoration: none;
}

.logo-badge {
    width: 34px;
    height: 34px;
    border-radius: 10px;
    background: var(--accent);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 700;
}

/* === HERO === */
.hero {
    padding: 5rem 0 3.5rem;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.45rem 1.1rem;
    background: var(--accent-light);
    color: var(--accent);
    border-radius: 999px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.2rem);
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-muted);
    max-width: 680px;
    margin: 0 auto 2rem;
}

/* === CONTENT === */
.content {
    padding: 2rem 0 5rem;
}

.section {
    margin-bottom: 4rem;
}

.section h2 {
    font-size: 1.7rem;
    font-weight: 700;
    margin-bottom: 1.2rem;
    letter-spacing: -0.01em;
}

.section p {
    font-size: 1.05rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
    line-height: 1.75;
}

.section ul {
    list-style: none;
}

.section li {
    font-size: 1.05rem;
    padding: 0.75rem 0;
    padding-left: 1.8rem;
    position: relative;
    color: var(--text-muted);
}

.section li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success);
    font-weight: 600;
}

/* === CARDS === */
.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.2rem;
    margin: 2rem 0;
}

.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    transition: all 0.25s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.card-icon {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    background: var(--accent-light);
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    margin-bottom: 0.8rem;
}

.card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 0.4rem;
}

.card p {
    font-size: 0.95rem;
    color: var(--text-muted);
}

/* === EXAMPLE === */
.example {
    background: var(--bg-alt);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 1.5rem;
    margin: 2rem 0;
}

.example-title {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 0.75rem;
}

/* === CODE === */
.code {
    font-family: 'JetBrains Mono', 'SF Mono', monospace;
    font-size: 0.95rem;
    line-height: 1.7;
    background: #0f172a;
    color: #e2e8f0;
    padding: 1.25rem;
    border-radius: 10px;
    overflow-x: auto;
}

.code .kw { color: #c084fc; }
.code .str { color: #34d399; }
.code .com { color: #64748b; display: block; }
.code .fn { color: #60a5fa; }

/* === DIAGRAM === */
.diagram {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1.2rem;
    padding: 2.5rem 1rem;
    flex-wrap: wrap;
}

.diag-box {
    padding: 1rem 1.5rem;
    background: var(--card);
    border: 2px solid var(--accent);
    border-radius: 12px;
    font-weight: 500;
    font-size: 1.2rem;
    text-align: center;
    min-width: 260px;
}

.diag-box.ai {
    background: var(--accent);
    color: #fff;
}

.diag-arrow {
    color: var(--text-muted);
    font-size: 1.5rem;
}

/* === CTA === */
.cta {
    text-align: center;
    padding: 3rem 0;
    border-top: 1px solid var(--border);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.2s ease;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(79,70,229,0.3);
    background: #4338ca;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text);
}

.btn-outline:hover {
    background: var(--bg-alt);
}

.btn-group {
    display: flex;
    gap: 0.8rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1rem;
}

/* === FOOTER === */
footer {
    padding: 2rem 0;
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

footer a {
    color: var(--accent);
    text-decoration: none;
}

/* === RESPONSIVE === */
@media (max-width: 640px) {
    .container { padding: 0 1.25rem; }

    .hero {
        padding: 3.5rem 0 2.5rem;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1.1rem;
    }

    .btn-group {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }
}