:root {
  --bg: #0a0a0a;
  --surface: #181c27;
  --surface2: #1f2435;
  --border: #2a3045;
  --accent: linear-gradient(135deg, #ffffff 0%, #a0a0a0 100%);
  --accent2: #a78bfa;
  --amber: #fbbf24;
  --red: #f87171;
  --text: #e2e8f0;
  --muted: #a0a0a0;
  --code-bg: #151515;
  --font-sans:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", monospace;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.7;
}

/* Layout */
.layout {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 260px;
  flex-shrink: 0;
  background: var(--surface);
  border-right: 1px solid var(--border);
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  overflow-y: auto;
  padding: 28px 0;
}

.sidebar-logo {
  padding: 0 24px 24px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 20px;
}

.sidebar-logo .name {
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.sidebar-logo .tagline {
  font-size: 11px;
  color: var(--muted);
  margin-top: 2px;
  letter-spacing: 0.04em;
}

.nav-group {
  margin-bottom: 8px;
}

.nav-group-label {
  font-size: 10px;
  font-weight: 600;
  color: var(--muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 6px 24px;
}

.nav-link {
  display: block;
  padding: 7px 24px;
  font-size: 13px;
  color: #94a3b8;
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: all 0.15s;
}

.nav-link:hover {
  color: var(--text);
  background: var(--surface2);
}
.nav-link.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: rgba(79, 156, 249, 0.06);
}

/* Main */
.main {
  max-width: 870px;
  margin-left: 260px;
  flex: 1;
  padding: 56px 64px;
}

/* Sections */
.section {
  margin-bottom: 72px;
}

h1 {
  font-size: 32px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
  line-height: 1.3;
}

h2 {
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 16px;
  margin-top: 48px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

h3 {
  font-size: 15px;
  font-weight: 600;
  color: #cbd5e1;
  margin-bottom: 12px;
  margin-top: 32px;
}

p {
  color: #94a3b8;
  margin-bottom: 14px;
  line-height: 1.8;
}

strong {
  color: var(--text);
  font-weight: 500;
}

.lead {
  font-size: 16px;
  color: #94a3b8;
  line-height: 1.8;
  margin-bottom: 32px;
  max-width: 620px;
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 11px;
  font-weight: 500;
  padding: 3px 9px;
  border-radius: 20px;
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}
.badge-blue {
  background: rgba(79, 156, 249, 0.12);
  color: var(--accent);
  border: 1px solid rgba(79, 156, 249, 0.2);
}
.badge-green {
  background: rgba(52, 211, 153, 0.1);
  color: var(--accent);
  border: 1px solid rgba(52, 211, 153, 0.2);
}
.badge-amber {
  background: rgba(251, 191, 36, 0.1);
  color: var(--amber);
  border: 1px solid rgba(251, 191, 36, 0.2);
}
.badge-red {
  background: rgba(248, 113, 113, 0.1);
  color: var(--red);
  border: 1px solid rgba(248, 113, 113, 0.2);
}

/* Info boxes */
.callout {
  border-radius: 8px;
  padding: 14px 18px;
  margin: 20px 0;
  font-size: 13.5px;
  line-height: 1.7;
  display: flex;
  gap: 12px;
}
.callout-icon {
  font-size: 15px;
  flex-shrink: 0;
  margin-top: 1px;
}
.callout p {
  margin: 0;
}
.callout-info {
  background: linear-gradient(
    135deg,
    rgba(243, 156, 18, 0.08) 0%,
    rgba(243, 156, 18, 0.03) 100%
  );
  border-color: rgba(243, 156, 18, 0.2);
  border: 1px solid rgba(79, 156, 249, 0.2);
  color: #93c5fd;
}
.callout-warn {
  background: rgba(251, 191, 36, 0.08);
  border: 1px solid rgba(251, 191, 36, 0.2);
  color: #fde68a;
}
.callout-success {
  background: rgba(52, 211, 153, 0.08);
  border: 1px solid rgba(52, 211, 153, 0.2);
  color: #6ee7b7;
}

/* Code blocks */
pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px 22px;
  overflow-x: auto;
  margin: 16px 0;
  position: relative;
}

pre .lang-label {
  position: absolute;
  top: 10px;
  right: 14px;
  font-size: 10px;
  color: var(--muted);
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: lowercase;
}

code {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.9;
}

p code,
li code {
  background: var(--surface2);
  border: 1px solid var(--border);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 12.5px;
  color: #93c5fd;
}

/* Syntax highlighting */
.kw {
  color: #a78bfa;
} /* keywords */
.ty {
  color: #34d399;
} /* types */
.fn {
  color: #60a5fa;
} /* functions */
.st {
  color: #f9a8d4;
} /* strings */
.nm {
  color: #fb923c;
} /* numbers */
.cm {
  color: #475569;
  font-style: italic;
} /* comments */
.inc {
  color: #2dd4bf;
} /* includes */
.op {
  color: #94a3b8;
} /* operators */
.bl {
  color: #facc15;
} /* booleans */

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 13.5px;
}

th {
  text-align: left;
  padding: 10px 16px;
  background: linear-gradient(
    135deg,
    rgba(243, 156, 18, 0.08) 0%,
    rgba(243, 156, 18, 0.03) 100%
  );
  border-color: rgba(243, 156, 18, 0.2);
  color: #94a3b8;
  font-weight: 500;
  font-size: 12px;
  letter-spacing: 0.04em;
  border-bottom: 1px solid var(--border);
}

td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  color: #94a3b8;
}

td:first-child {
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 13px;
}

tr:last-child td {
  border-bottom: none;
}

tbody tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

/* Terminal blocks */
.terminal {
  background: #0a0c12;
  border: 1px solid #1e2535;
  border-radius: 10px;
  overflow: hidden;
  margin: 16px 0;
}

.terminal img {
  width: 100%;
  height: 100%;
}

.terminal-bar {
  background: #141824;
  padding: 9px 16px;
  display: flex;
  align-items: center;
  gap: 6px;
  border-bottom: 1px solid #1e2535;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.dot-r {
  background: #ff5f57;
}
.dot-y {
  background: #febc2e;
}
.dot-g {
  background: #28c840;
}

.terminal-body {
  padding: 16px 20px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.8;
}

.terminal-body .prompt {
  color: var(--accent);
}
.terminal-body .cmd {
  color: var(--text);
}
.terminal-body .out {
  color: var(--muted);
}

/* Type cards */
.type-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 12px;
  margin: 20px 0;
}

.type-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px 18px;
}

.type-card .type-name {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  color: var(--accent);
  margin-bottom: 4px;
}

.type-card .type-desc {
  font-size: 12px;
  color: var(--muted);
  line-height: 1.5;
}

.type-card .type-example {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

/* Rule separator */
.rule {
  border: none;
  border-top: 1px solid var(--border);
  margin: 48px 0;
}

/* Hero */
.hero {
  margin-bottom: 56px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border);
}

.hero-badges {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

/* Two column */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 20px 0;
}
@media (max-width: 600px) {
  .two-col {
    grid-template-columns: 1fr;
  }
}

/* Numbered steps */
.steps {
  counter-reset: step;
}

.step {
  display: flex;
  gap: 20px;
  margin-bottom: 32px;
  position: relative;
}

.step-num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--surface2);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  flex-shrink: 0;
  margin-top: 2px;
  font-family: var(--font-mono);
}

.step-body {
  flex: 1;
}
.step-body h4 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

ul,
ol {
  padding-left: 20px;
  color: #94a3b8;
  margin-bottom: 16px;
}
li {
  margin-bottom: 6px;
  font-size: 14px;
}
li code {
  font-size: 12px;
}

/* ── Mobile topbar ── */
.topbar {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 52px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  align-items: center;
  justify-content: space-between;
  padding: 0 18px;
  z-index: 200;
}

.topbar-logo {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.hamburger {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 9px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hamburger span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all 0.2s;
}

/* Sidebar overlay on mobile */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  z-index: 149;
}

.sidebar-overlay.active {
  display: block;
}

/* Scrollable tables on small screens */
.table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 20px 0;
  border-radius: 8px;
  border: 1px solid var(--border);
}

.table-wrap table {
  margin: 0;
  border: none;
}
.table-wrap th,
.table-wrap td {
  white-space: nowrap;
}

/* ── Breakpoints ── */

/* Tablet — 900px */
@media (max-width: 900px) {
  .main {
    padding: 40px 36px;
  }
}

/* Mobile — 768px: sidebar becomes a drawer */
@media (max-width: 768px) {
  .topbar {
    display: flex;
  }

  .sidebar {
    padding-top: 15%;
    transform: translateX(-100%);
    transition: transform 0.25s ease;
    z-index: 150;
    top: 0;
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .main {
    max-width: 100vw;
    margin-left: 0;
    padding: 80px 20px 40px;
  }

  h1 {
    font-size: 26px;
  }
  h2 {
    font-size: 18px;
  }

  .lead {
    font-size: 14px;
  }

  pre {
    padding: 14px 14px;
    font-size: 12px;
  }

  code {
    font-size: 12px;
  }

  .two-col {
    grid-template-columns: 1fr;
  }

  .type-grid {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  }

  .terminal-body {
    font-size: 11.5px;
    padding: 12px 14px;
  }

  table {
    font-size: 12.5px;
  }
  th,
  td {
    padding: 8px 12px;
  }

  .step {
    gap: 14px;
  }

  .callout {
    font-size: 13px;
    padding: 12px 14px;
  }

  .section {
    margin-bottom: 48px;
  }
}

/* Small mobile — 420px */
@media (max-width: 420px) {
  .main {
    padding: 72px 14px 32px;
  }

  h1 {
    font-size: 22px;
  }

  pre {
    padding: 12px;
    font-size: 11.5px;
  }

  .type-grid {
    grid-template-columns: 1fr 1fr;
  }

  .hero-badges {
    gap: 6px;
  }
}