:root {
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  --bg-app: #0b0f19;
  --bg-card: #111827;
  --bg-card-subtle: #1e293b;
  --bg-sidebar: #090d16;
  --border-color: #1f293d;
  --border-subtle: #334155;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-faint: #64748b;
  --brand: #3b82f6;
  --brand-gradient: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
  --accent-cyan: #06b6d4;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;
  --accent-rose: #f43f5e;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-app);
  color: var(--text-main);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.6;
}

/* Header */
.docs-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: 64px;
  background: rgba(11, 15, 25, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 28px;
}
.docs-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: #fff;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.brand-badge {
  font-size: 11px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 9999px;
  background: rgba(59, 130, 246, 0.15);
  color: #60a5fa;
  border: 1px solid rgba(59, 130, 246, 0.3);
}
.header-nav {
  display: flex;
  align-items: center;
  gap: 16px;
}
.header-nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
  transition: color 0.15s;
}
.header-nav a:hover { color: #fff; }
.header-btn {
  background: var(--brand);
  color: #fff !important;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  transition: opacity 0.15s;
}
.header-btn:hover { opacity: 0.9; }

/* Main Layout */
.docs-layout {
  display: flex;
  min-height: calc(100vh - 64px);
}
.docs-sidebar {
  width: 280px;
  position: sticky;
  top: 64px;
  height: calc(100vh - 64px);
  overflow-y: auto;
  border-right: 1px solid var(--border-color);
  background: var(--bg-sidebar);
  padding: 24px 16px;
  flex-shrink: 0;
}
.sidebar-group-title {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-faint);
  margin: 18px 0 8px 12px;
}
.sidebar-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  color: var(--text-muted);
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 500;
  transition: all 0.15s;
}
.sidebar-link:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.05);
}
.sidebar-link.active {
  color: #60a5fa;
  background: rgba(59, 130, 246, 0.1);
  font-weight: 600;
}
.sidebar-badge {
  margin-left: auto;
  font-size: 10px;
  padding: 1px 6px;
  border-radius: 4px;
  font-weight: 700;
}
.badge-post { background: rgba(16, 185, 129, 0.2); color: #34d399; }
.badge-get { background: rgba(59, 130, 246, 0.2); color: #60a5fa; }

/* Content Area */
.docs-content {
  flex: 1;
  max-width: 960px;
  padding: 40px 48px 120px;
}
.docs-hero {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 32px;
  margin-bottom: 40px;
}
.docs-hero h1 {
  font-size: 32px;
  font-weight: 800;
  margin: 0 0 12px;
  background: linear-gradient(135deg, #fff 40%, #94a3b8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.docs-hero p {
  font-size: 16px;
  color: var(--text-muted);
  margin: 0;
  max-width: 720px;
}

/* Sections */
.doc-section {
  margin-bottom: 56px;
  scroll-margin-top: 84px;
}
.doc-section h2 {
  font-size: 22px;
  font-weight: 700;
  margin: 0 0 16px;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 10px;
}
.doc-section h3 {
  font-size: 17px;
  font-weight: 600;
  margin: 28px 0 12px;
  color: #e2e8f0;
}
.doc-section p, .doc-section li {
  color: var(--text-muted);
  line-height: 1.7;
}

/* Callout Box */
.callout {
  background: rgba(30, 41, 59, 0.6);
  border: 1px solid var(--border-subtle);
  border-left: 4px solid var(--brand);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin: 20px 0;
}
.callout.warning {
  border-left-color: var(--accent-amber);
  background: rgba(245, 158, 11, 0.08);
}
.callout.success {
  border-left-color: var(--accent-emerald);
  background: rgba(16, 185, 129, 0.08);
}
.callout strong { color: #fff; }

/* API Endpoint Header */
.endpoint-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  margin: 16px 0;
  font-family: var(--font-mono);
  font-size: 14px;
}
.method-tag {
  font-weight: 700;
  font-size: 12px;
  padding: 3px 8px;
  border-radius: 4px;
}
.method-post { background: #059669; color: #fff; }
.method-get { background: #2563eb; color: #fff; }
.endpoint-path { color: #38bdf8; font-weight: 600; }

/* Parameters Table */
.param-table-wrap {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin: 18px 0;
}
.param-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 13px;
}
.param-table th {
  background: #0f172a;
  color: var(--text-muted);
  font-weight: 600;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border-color);
}
.param-table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border-color);
  color: #cbd5e1;
}
.param-table tr:last-child td { border-bottom: none; }
.param-name { font-family: var(--font-mono); color: #38bdf8; font-weight: 600; }
.param-type { font-family: var(--font-mono); color: #94a3b8; font-size: 12px; }
.param-req { color: #f43f5e; font-size: 11px; font-weight: 700; margin-left: 4px; }
.param-opt { color: #64748b; font-size: 11px; margin-left: 4px; }

/* Code Blocks & Tabs */
.code-card {
  background: #090d16;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin: 20px 0;
}
.code-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #0f172a;
  border-bottom: 1px solid var(--border-color);
  padding: 6px 12px;
}
.lang-tabs {
  display: flex;
  gap: 4px;
}
.lang-tab {
  background: transparent;
  border: none;
  color: var(--text-faint);
  font-size: 12px;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.15s;
}
.lang-tab:hover { color: #fff; }
.lang-tab.active { background: #1e293b; color: #38bdf8; }
.copy-btn {
  background: rgba(255, 255, 255, 0.08);
  border: none;
  color: var(--text-muted);
  font-size: 11px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.15s;
}
.copy-btn:hover { background: rgba(255, 255, 255, 0.15); color: #fff; }
.code-pre {
  margin: 0;
  padding: 16px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.6;
  color: #e2e8f0;
}

/* Playground / HMAC Debugger */
.debugger-card {
  background: #0f172a;
  border: 1px solid #1e3a8a;
  border-radius: var(--radius-lg);
  padding: 24px;
  margin: 24px 0;
}
.debugger-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
@media (max-width: 860px) {
  .debugger-grid { grid-template-columns: 1fr; }
}
.form-group {
  margin-bottom: 14px;
}
.form-group label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 6px;
}
.form-control {
  width: 100%;
  background: #090d16;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: #fff;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
}
.form-control:focus {
  outline: none;
  border-color: var(--brand);
}
.debugger-result {
  background: #090d16;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px;
}
.result-item {
  margin-bottom: 14px;
}
.result-label {
  font-size: 11px;
  color: var(--text-faint);
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 4px;
}
.result-code {
  font-family: var(--font-mono);
  font-size: 12px;
  color: #38bdf8;
  word-break: break-all;
  background: rgba(56, 189, 248, 0.08);
  padding: 6px 10px;
  border-radius: 4px;
  border: 1px solid rgba(56, 189, 248, 0.2);
}

/* Responsive */
@media (max-width: 900px) {
  .docs-sidebar { display: none; }
  .docs-content { padding: 24px 20px 80px; }
}