:root {
    --bg: #0d1117;
    --bg-alt: #161b22;
    --surface: #1c2128;
    --border: #30363d;
    --text: #e6edf3;
    --text-dim: #8b949e;
    --text-bright: #ffffff;
    --accent: #8b5cf6;
    --accent-dim: rgba(139, 92, 246, 0.12);
    --teal: #14b8a6;
    --teal-dim: rgba(20, 184, 166, 0.12);
    --green: #4ade80;
    --green-dim: rgba(74, 222, 128, 0.12);
    --red: #f87171;
    --red-dim: rgba(248, 113, 113, 0.12);
    --yellow: #fbbf24;
    --yellow-dim: rgba(251, 191, 36, 0.12);
    --code-bg: #0d1117;
    --max-width: 1120px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.65;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

/* ── Layout ── */
.section { padding: 96px 32px; }
.section:nth-child(even) { background: var(--bg-alt); }
.container { max-width: var(--max-width); margin: 0 auto; }

/* ── Typography ── */
h1 { font-size: 52px; font-weight: 700; line-height: 1.15; letter-spacing: -1.5px; color: var(--text-bright); }
h2 { font-size: 32px; font-weight: 600; line-height: 1.25; letter-spacing: -0.5px; margin-bottom: 16px; }
h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
p { color: var(--text-dim); max-width: 640px; }
.section-label {
    font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 2px;
    color: var(--accent); margin-bottom: 12px;
}

/* ── Hero ── */
.hero { padding: 140px 32px 120px; text-align: center; }
.hero .container { max-width: 800px; }
.hero h1 { margin-bottom: 20px; }
.hero h1 .accent { color: var(--accent); }
.hero .subtitle {
    font-size: 20px; color: var(--text-dim); margin-bottom: 12px; font-weight: 400;
}
.hero .desc { margin: 0 auto 40px; font-size: 17px; line-height: 1.7; }
.hero .ctas { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 12px 24px; border-radius: 8px; font-size: 15px; font-weight: 500;
    text-decoration: none; transition: all 0.15s;
}
.btn-primary { background: var(--accent); color: white; }
.btn-primary:hover { filter: brightness(1.15); }
.btn-secondary { background: var(--surface); color: var(--text); border: 1px solid var(--border); }
.btn-secondary:hover { border-color: var(--text-dim); }

/* ── Problem Cards ── */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 40px; }
.card {
    background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
    padding: 28px 24px;
}
.card .icon { font-size: 28px; margin-bottom: 12px; }
.card h3 { color: var(--text-bright); }
.card p { font-size: 14px; line-height: 1.6; max-width: none; }
.cards-note { margin-top: 32px; font-size: 15px; text-align: center; }

/* ── Steps ── */
.steps { display: grid; gap: 0; margin-top: 40px; position: relative; }
.step {
    display: grid; grid-template-columns: 56px 1fr; gap: 20px;
    padding: 24px 0; position: relative;
}
.step-num {
    width: 40px; height: 40px; border-radius: 50%;
    background: var(--accent-dim); color: var(--accent);
    display: flex; align-items: center; justify-content: center;
    font-size: 15px; font-weight: 700; flex-shrink: 0;
    border: 2px solid var(--accent);
}
.step h3 { margin-bottom: 4px; }
.step p { font-size: 14px; }
.step code {
    display: inline-block; background: var(--code-bg); border: 1px solid var(--border);
    padding: 2px 8px; border-radius: 4px; font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 13px; color: var(--teal); margin-bottom: 4px;
}
.step-line {
    position: absolute; left: 51px; top: 64px; bottom: 0; width: 2px;
    background: var(--border);
}
.step:last-child .step-line { display: none; }

/* ── Layers ── */
.layers { margin-top: 40px; display: grid; gap: 2px; }
.layer {
    background: var(--surface); border: 1px solid var(--border); border-radius: 8px;
    padding: 24px; display: grid; grid-template-columns: 180px 1fr; gap: 24px;
    align-items: start;
}
.layer-badge {
    font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 1.5px;
    padding: 6px 12px; border-radius: 6px; text-align: center;
}
.layer-badge.rules { background: var(--red-dim); color: var(--red); }
.layer-badge.memory { background: var(--accent-dim); color: var(--accent); }
.layer-badge.env { background: var(--teal-dim); color: var(--teal); }
.layer-priority {
    font-size: 11px; color: var(--text-dim); text-align: center; margin-top: 4px;
}
.layer h3 { margin-bottom: 4px; }
.layer p { font-size: 14px; max-width: none; }
.layer-example {
    margin-top: 12px; background: var(--code-bg); border: 1px solid var(--border);
    border-radius: 6px; padding: 12px 16px; font-family: 'JetBrains Mono', monospace;
    font-size: 12px; color: var(--text-dim); white-space: pre; overflow-x: auto;
}
.hierarchy-note {
    margin-top: 24px; text-align: center; font-size: 15px;
    padding: 16px; background: var(--surface); border: 1px solid var(--border); border-radius: 8px;
}
.hierarchy-note strong { color: var(--text-bright); }

/* ── Code Blocks ── */
.code-block {
    position: relative; background: var(--code-bg); border: 1px solid var(--border);
    border-radius: 10px; margin-top: 32px; overflow: hidden;
}
.code-block .header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 10px 16px; background: var(--surface); border-bottom: 1px solid var(--border);
    font-size: 12px; color: var(--text-dim);
}
.code-block pre {
    padding: 20px 24px; overflow-x: auto; font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 13px; line-height: 1.7; color: var(--text);
}
.code-block pre .comment { color: var(--text-dim); }
.code-block pre .cmd { color: var(--teal); }
.code-block pre .string { color: var(--green); }
.code-block pre .key { color: var(--accent); }
.copy-btn {
    background: var(--bg); border: 1px solid var(--border); border-radius: 4px;
    color: var(--text-dim); padding: 4px 10px; cursor: pointer; font-size: 12px;
    transition: all 0.15s;
}
.copy-btn:hover { color: var(--text); border-color: var(--text-dim); }
.copy-btn.copied { color: var(--green); border-color: var(--green); }
.code-note { margin-top: 16px; font-size: 14px; text-align: center; }

/* ── Comparison Table ── */
.table-wrap { margin-top: 32px; overflow-x: auto; border-radius: 10px; border: 1px solid var(--border); }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th {
    background: var(--surface); padding: 12px 16px; text-align: left;
    font-weight: 600; font-size: 13px; color: var(--text-dim);
    border-bottom: 1px solid var(--border); position: sticky; top: 0;
}
td { padding: 10px 16px; border-bottom: 1px solid var(--border); }
tr:nth-child(even) { background: var(--bg-alt); }
tr:hover { background: var(--surface); }
td:first-child { font-weight: 500; color: var(--text); }
.check { color: var(--green); font-weight: 700; }
.dash { color: var(--text-dim); }
.partial { color: var(--yellow); }
.table-note { margin-top: 24px; font-size: 14px; text-align: center; }

/* ── API Reference ── */
.endpoint { margin-top: 40px; }
.endpoint:first-child { margin-top: 32px; }
.endpoint-header {
    display: flex; align-items: center; gap: 12px; margin-bottom: 12px;
}
.method {
    padding: 4px 10px; border-radius: 4px; font-size: 12px; font-weight: 700; font-family: monospace;
    background: var(--green-dim); color: var(--green);
}
.path { font-family: monospace; font-size: 15px; font-weight: 500; }
.endpoint p { font-size: 14px; margin-bottom: 12px; }
.endpoint .code-block { margin-top: 12px; }
.endpoint-types {
    margin-top: 12px; display: flex; gap: 8px; flex-wrap: wrap; font-size: 12px;
}
.endpoint-types span {
    padding: 2px 8px; border-radius: 4px; background: var(--surface); border: 1px solid var(--border);
    font-family: monospace;
}

/* ── Footer ── */
.footer {
    padding: 48px 32px; text-align: center; border-top: 1px solid var(--border);
    font-size: 14px; color: var(--text-dim);
}
.footer a { color: var(--accent); text-decoration: none; }
.footer a:hover { text-decoration: underline; }
.footer .links { margin-top: 8px; }
.footer .links a { margin: 0 12px; }

/* ── Responsive ── */
@media (max-width: 768px) {
    h1 { font-size: 36px; }
    h2 { font-size: 26px; }
    .section { padding: 64px 20px; }
    .hero { padding: 100px 20px 80px; }
    .cards { grid-template-columns: 1fr; }
    .layer { grid-template-columns: 1fr; }
    .hero .ctas { flex-direction: column; align-items: center; }
    .code-block pre { font-size: 12px; padding: 16px; }
}