:root {
  --font-display: "Bricolage Grotesque", "Hanken Grotesk", system-ui, sans-serif;
  --font-sans: "Hanken Grotesk", system-ui, -apple-system, Segoe UI, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --ink-900: #23272B;
  --ink-800: #2E3338;
  --ink-600: #5C6268;
  --ink-500: #7C838A;
  --ink-400: #A3AAB1;
  --ink-200: #E1E4E7;
  --ink-100: #EEF0F2;
  --ink-50:  #F6F7F9;
  --paper:   #F7F9FB;
  --white:   #FFFFFF;

  --accent:       #18A8E0;
  --accent-hover: #1389C2;
  --accent-press: #0A6E97;
  --ocean:        #136C90;

  --bg: var(--paper);
  --surface: var(--white);
  --text: var(--ink-900);
  --text-muted: var(--ink-600);
  --border: var(--ink-200);
  --code-bg: var(--ink-50);

  --radius: 10px;
  --radius-sm: 6px;
  --sidebar-w: 264px;
  --header-h: 56px;
  --content-max: 760px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1A1D20;
    --surface: #202427;
    --text: #EAECEE;
    --text-muted: #A3AAB1;
    --border: #333A40;
    --code-bg: #15181A;
    --accent: #45BBE8;
    --accent-hover: #84D2F0;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 20;
  height: var(--header-h);
  display: flex; align-items: center; gap: 16px;
  padding: 0 20px;
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand {
  display: flex; align-items: center; gap: 9px;
  font-family: var(--font-display); font-weight: 800; font-size: 18px;
  color: var(--text); text-decoration: none;
}
.brand img { display: block; border-radius: 5px; }
.brand-accent { color: var(--accent); }
.header-links { margin-left: auto; display: flex; gap: 20px; }
.header-links a { color: var(--text-muted); text-decoration: none; font-size: 14px; font-weight: 500; }
.header-links a:hover { color: var(--accent); }
.menu-toggle {
  display: none; margin-left: auto;
  background: none; border: 1px solid var(--border); border-radius: var(--radius-sm);
  color: var(--text); font-size: 18px; padding: 4px 10px; cursor: pointer;
}

/* Layout */
.layout { display: flex; align-items: flex-start; }
.sidebar {
  position: sticky; top: var(--header-h);
  width: var(--sidebar-w); flex: 0 0 var(--sidebar-w);
  height: calc(100vh - var(--header-h));
  overflow-y: auto;
  padding: 24px 16px 48px;
  border-right: 1px solid var(--border);
}
.nav-section { margin-bottom: 22px; }
.nav-heading {
  font-family: var(--font-display); font-weight: 700;
  font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-400); padding: 0 10px; margin-bottom: 6px;
}
.nav-link {
  display: block; padding: 5px 10px; border-radius: var(--radius-sm);
  color: var(--text-muted); text-decoration: none; font-size: 14px;
}
.nav-link:hover { background: var(--code-bg); color: var(--text); }
.nav-link.active {
  background: color-mix(in srgb, var(--accent) 14%, transparent);
  color: var(--accent-press); font-weight: 600;
}
@media (prefers-color-scheme: dark) { .nav-link.active { color: var(--accent); } }

/* Content */
.content {
  flex: 1 1 auto; min-width: 0;
  padding: 40px clamp(20px, 5vw, 56px) 80px;
  display: flex; flex-direction: column; align-items: center;
}
.doc { width: 100%; max-width: var(--content-max); }
.doc-footer {
  width: 100%; max-width: var(--content-max);
  margin-top: 64px; padding-top: 20px; border-top: 1px solid var(--border);
  color: var(--ink-400); font-size: 13px;
}
.doc-footer a { color: var(--text-muted); }

/* Typography */
.doc h1, .doc h2, .doc h3, .doc h4 {
  font-family: var(--font-display); font-weight: 700;
  line-height: 1.2; color: var(--text); scroll-margin-top: calc(var(--header-h) + 16px);
}
.doc h1 { font-size: 34px; margin: 0 0 20px; letter-spacing: -0.01em; }
.doc h2 { font-size: 24px; margin: 40px 0 14px; padding-top: 8px; }
.doc h3 { font-size: 18px; margin: 28px 0 10px; }
.doc p { margin: 0 0 16px; }
.doc a { color: var(--accent); text-decoration: none; }
.doc a:hover { color: var(--accent-hover); text-decoration: underline; }
.doc ul, .doc ol { margin: 0 0 16px; padding-left: 24px; }
.doc li { margin: 4px 0; }
.doc strong { font-weight: 700; color: var(--text); }
.doc blockquote {
  margin: 0 0 16px; padding: 2px 16px;
  border-left: 3px solid var(--accent);
  background: color-mix(in srgb, var(--accent) 7%, transparent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-muted);
}
.doc blockquote p { margin: 8px 0; }
.doc hr { border: none; border-top: 1px solid var(--border); margin: 32px 0; }

/* Code */
.doc code {
  font-family: var(--font-mono); font-size: 0.88em;
  background: var(--code-bg); border: 1px solid var(--border);
  border-radius: 5px; padding: 1px 5px;
}
.doc pre {
  background: var(--code-bg); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 16px; overflow-x: auto; margin: 0 0 18px;
}
.doc pre code { background: none; border: none; padding: 0; font-size: 13px; line-height: 1.6; }

/* Tables */
.doc table {
  width: 100%; border-collapse: collapse; margin: 0 0 20px;
  font-size: 14px; display: block; overflow-x: auto;
}
.doc thead { background: var(--code-bg); }
.doc th, .doc td {
  text-align: left; padding: 8px 12px; border: 1px solid var(--border);
  vertical-align: top;
}
.doc th { font-family: var(--font-display); font-weight: 600; white-space: nowrap; }
.doc td code { white-space: nowrap; }

/* Home landing */
.home-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 14px; margin-top: 28px;
}
.home-card {
  display: block; padding: 18px; text-decoration: none;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.home-card:hover { border-color: var(--accent); transform: translateY(-2px); text-decoration: none; }
.home-card-title {
  font-family: var(--font-display); font-weight: 700; font-size: 16px;
  color: var(--text); margin-bottom: 4px;
}
.home-card-desc { color: var(--text-muted); font-size: 14px; }

/* Responsive */
@media (max-width: 900px) {
  .menu-toggle { display: block; }
  .header-links { display: none; }
  .sidebar {
    position: fixed; left: 0; top: var(--header-h); z-index: 15;
    background: var(--surface); transform: translateX(-100%);
    transition: transform 0.2s ease; box-shadow: 0 8px 30px rgba(0,0,0,0.12);
  }
  body.nav-open .sidebar { transform: translateX(0); }
  .content { padding: 28px 20px 64px; }
}