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

:root {
  --bg: #f8f9fb;
  --surface: #ffffff;
  --surface-alt: #f1f3f7;
  --border: #e2e6ed;
  --accent: #4f6ef7;
  --accent-light: #eef0fe;
  --text: #1a1d23;
  --text-secondary: #5a6278;
  --success: #22c55e;
  --warning: #f59e0b;
  --code-bg: #f1f3f7;
  --radius: 10px;
  --shadow: 0 2px 12px rgba(0,0,0,0.07);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 15px;
}

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

/* ── Layout ── */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 2rem;
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.site-header .logo {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.site-header nav { display: flex; gap: 0.25rem; }

.site-header nav a {
  padding: 0.35rem 0.85rem;
  border-radius: 6px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: background 0.15s, color 0.15s;
}

.site-header nav a:hover,
.site-header nav a.active {
  background: var(--accent-light);
  color: var(--accent);
  text-decoration: none;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem 5rem;
}

/* ── Hero ── */
.hero {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.5rem 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
}

.hero h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.hero p { color: var(--text-secondary); max-width: 600px; }

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  margin-top: 1.25rem;
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.meta-item strong { color: var(--text); }

/* ── Lab cards on index ── */
.lab-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
  margin-top: 1.5rem;
}

.lab-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: box-shadow 0.2s, border-color 0.2s;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.lab-card:hover {
  box-shadow: 0 4px 20px rgba(79,110,247,0.12);
  border-color: var(--accent);
  text-decoration: none;
}

.lab-card .lab-num {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.lab-card h2 { font-size: 1rem; font-weight: 600; color: var(--text); }
.lab-card p { font-size: 0.85rem; color: var(--text-secondary); }

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.6rem;
  border-radius: 99px;
  font-size: 0.75rem;
  font-weight: 600;
  background: #dcfce7;
  color: #16a34a;
  width: fit-content;
}

.badge.wip { background: #fef9c3; color: #a16207; }

/* ── Section ── */
.section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem 2rem;
  margin-bottom: 1.25rem;
  box-shadow: var(--shadow);
}

.section h2 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 1rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin: 1.25rem 0 0.5rem;
  color: var(--text);
}

.section p { color: var(--text-secondary); margin-bottom: 0.75rem; }
.section p:last-child { margin-bottom: 0; }

/* ── Code ── */
pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  overflow-x: auto;
  font-size: 0.82rem;
  line-height: 1.6;
  margin: 0.75rem 0;
}

code {
  font-family: "JetBrains Mono", "Fira Code", "Cascadia Code", monospace;
  font-size: 0.85em;
  background: var(--code-bg);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  border: 1px solid var(--border);
}

pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}

/* ── Table ── */
.table-wrap { overflow-x: auto; margin: 0.75rem 0; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}

th {
  background: var(--surface-alt);
  padding: 0.6rem 0.9rem;
  text-align: left;
  font-weight: 600;
  border: 1px solid var(--border);
}

td {
  padding: 0.55rem 0.9rem;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  vertical-align: top;
}

tr:hover td { background: var(--surface-alt); }

/* ── Endpoint list ── */
.endpoint-list { display: flex; flex-direction: column; gap: 0.5rem; margin-top: 0.5rem; }

.endpoint {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.65rem 0.9rem;
  border-radius: 7px;
  border: 1px solid var(--border);
  background: var(--surface-alt);
  font-size: 0.85rem;
}

.endpoint:hover { border-color: var(--accent); background: var(--accent-light); }

.method {
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.2rem 0.5rem;
  border-radius: 5px;
  min-width: 52px;
  text-align: center;
  flex-shrink: 0;
  margin-top: 1px;
}

.method.get    { background: #dbeafe; color: #1d4ed8; }
.method.post   { background: #dcfce7; color: #15803d; }
.method.patch  { background: #fef9c3; color: #a16207; }
.method.delete { background: #fee2e2; color: #dc2626; }

.endpoint-path { font-family: monospace; font-weight: 600; color: var(--text); }
.endpoint-desc { color: var(--text-secondary); margin-top: 0.1rem; font-size: 0.8rem; }

/* ── Commit timeline ── */
.timeline { display: flex; flex-direction: column; gap: 0; margin-top: 0.5rem; }

.timeline-item {
  display: flex;
  gap: 1rem;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border);
}

.timeline-item:last-child { border-bottom: none; }

.commit-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  margin-top: 6px;
  flex-shrink: 0;
}

.commit-info { flex: 1; }
.commit-msg { font-weight: 600; font-size: 0.875rem; }
.commit-sub { font-size: 0.8rem; color: var(--text-secondary); margin-top: 0.15rem; }

/* ── File tree ── */
.file-tree {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  font-family: monospace;
  font-size: 0.82rem;
  line-height: 1.8;
  white-space: pre-wrap;
  overflow-x: auto;
}

.file-tree .dir  { color: var(--accent); font-weight: 600; }
.file-tree .file { color: var(--text-secondary); }
.file-tree .note { color: #94a3b8; font-style: italic; }

/* ── Responsive ── */
@media (max-width: 600px) {
  .container { padding: 1.25rem 1rem 4rem; }
  .section { padding: 1.25rem; }
  .hero { padding: 1.5rem 1.25rem; }
  .hero h1 { font-size: 1.35rem; }
  .site-header { padding: 0 1rem; }
}