:root {
  --bg: #f0f7ff;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #4b5563;
  --blue: #2563eb;
  --line: #e2e8f0;
  --warn: #92400e;
  --warn-bg: #fffbeb;
  --ok: #166534;
  --ok-bg: #f0fdf4;
  --info: #1e3a8a;
  --sidebar: 280px;
  --radius: 8px;
}

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

html, body {
  font-family: system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100%;
}

a { color: var(--blue); }

.skip { position: absolute; left: -999px; }
.skip:focus { left: 8px; top: 8px; background: #fff; padding: 8px 12px; z-index: 50; }

.layout {
  display: grid;
  grid-template-columns: var(--sidebar) minmax(0, 1fr);
  max-width: 1080px;
  margin: 0 auto;
  min-height: 100vh;
  background: var(--bg);
  box-shadow: 0 0 40px rgba(15, 23, 42, 0.06);
}

.sidebar {
  background: #fff;
  border-right: 1px solid var(--line);
  padding: 20px 16px 32px;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: auto;
}

.brand { color: var(--blue); font-size: 18px; font-weight: 700; margin-bottom: 4px; }
.brand-sub { color: var(--muted); font-size: 12px; margin-bottom: 12px; }

.draft-badge {
  display: block;
  width: fit-content;
  background: var(--warn-bg);
  color: var(--warn);
  border: 1px solid #fde68a;
  border-radius: 999px;
  font-size: 12px;
  padding: 2px 8px;
  margin-bottom: 12px;
}

.sidebar label.muted {
  display: block;
}

.search {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 8px 10px;
  font-size: 14px;
  margin: 8px 0 16px;
}

.nav {
  font-size: 14px;
}

.nav-series {
  margin: 4px 0;
}

.nav-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  border: 0;
  background: transparent;
  color: #334155;
  text-align: left;
  padding: 8px 6px;
  border-radius: 6px;
  cursor: pointer;
  font: inherit;
}

.nav-series-toggle {
  font-weight: 600;
  color: #0f172a;
}

.nav-family-toggle {
  padding-left: 18px;
  color: #334155;
}

.nav-toggle:hover {
  background: #f8fafc;
}

.nav-chevron {
  width: 0;
  height: 0;
  border-top: 4px solid transparent;
  border-bottom: 4px solid transparent;
  border-left: 5px solid #94a3b8;
  flex: 0 0 auto;
  transform: rotate(0deg);
  transition: transform .15s ease;
}

.nav-series.is-open > .nav-series-toggle .nav-chevron,
.nav-family.is-open > .nav-family-toggle .nav-chevron {
  transform: rotate(90deg);
}

.nav-series-body,
.nav-family-body {
  display: none;
}

.nav-series.is-open > .nav-series-body,
.nav-family.is-open > .nav-family-body {
  display: block;
}

.nav a {
  display: block;
  text-decoration: none;
  color: var(--text);
  padding: 6px 8px 6px 40px;
  border-radius: 6px;
  font-size: 13px;
  word-break: break-all;
}

.nav > a {
  padding: 8px 6px;
  font-size: 14px;
  font-weight: 600;
  color: #0f172a;
}

.nav a:hover, .nav a.active {
  background: #eff6ff;
  color: var(--blue);
}

.nav a .nav-note {
  display: block;
  font-size: 11px;
  color: #b45309;
}

.hidden { display: none !important; }

.main {
  padding: 28px 32px 64px;
  min-width: 0;
}

.menu-btn {
  display: none;
  margin-bottom: 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 8px 12px;
  color: var(--blue);
  cursor: pointer;
}

h1 { font-size: 28px; color: var(--blue); margin-bottom: 8px; }
h2 { font-size: 20px; color: var(--blue); border-bottom: 1px solid var(--line); padding-bottom: 6px; margin: 32px 0 12px; }
h3 { font-size: 17px; color: #374151; margin: 22px 0 10px; }
.lead { color: var(--muted); margin-bottom: 20px; }

.tip, .warn, .ok, .note {
  border-radius: 0 6px 6px 0;
  padding: 12px 16px;
  margin: 16px 0;
}
.tip { background: #fff; border-left: 4px solid #3b82f6; color: var(--muted); }
.warn { background: var(--warn-bg); border-left: 4px solid #f59e0b; color: var(--warn); }
.ok { background: var(--ok-bg); border-left: 4px solid #22c55e; color: var(--ok); }
.note { background: #eff6ff; border-left: 4px solid var(--blue); color: var(--info); }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0 20px;
  border: 1px solid var(--line);
  background: #fff;
  font-size: 14px;
}
th, td {
  padding: 10px 12px;
  text-align: left;
  border: 1px solid var(--line);
  vertical-align: top;
}
th { background: #eff6ff; color: var(--blue); }

.code-wrap { position: relative; margin: 12px 0; }
pre {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  overflow-x: auto;
  font-size: 13px;
}
code { color: var(--blue); font-family: Consolas, Monaco, monospace; }
pre code { color: #1e293b; }

.copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  background: #eff6ff;
  color: var(--blue);
  border: 1px solid #bfdbfe;
  border-radius: 6px;
  padding: 4px 8px;
  font-size: 12px;
  cursor: pointer;
}

.id-chip {
  display: inline-block;
  background: #fff;
  border: 1px dashed #93c5fd;
  border-radius: 6px;
  padding: 2px 8px;
  font-family: Consolas, Monaco, monospace;
  color: var(--blue);
}

.param-list { display: grid; gap: 12px; margin: 12px 0 20px; }
.param-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 16px;
}
.param-head {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 6px;
}
.param-head code {
  background: #f1f5f9;
  border-radius: 6px;
  padding: 2px 8px;
  color: #0f172a;
}
.param-type {
  font-size: 12px;
  color: #2563eb;
  background: #eff6ff;
  border-radius: 999px;
  padding: 1px 8px;
}
.req-yes, .req-no, .req-maybe {
  margin-left: auto;
  font-size: 12px;
  border-radius: 999px;
  padding: 1px 8px;
}
.req-yes { color: #b91c1c; background: #fef2f2; }
.req-maybe { color: #b45309; background: #fffbeb; }
.req-no { color: #64748b; background: #f8fafc; }
.param-title { font-weight: 600; margin-bottom: 4px; }
.param-card p { color: var(--muted); font-size: 14px; }
.param-extra { color: #475569; font-size: 13px; margin-top: 4px; }

.billing-box {
  margin: 0 0 24px;
  padding: 16px 18px;
  border: 1px solid #bfdbfe;
  border-radius: 12px;
  background: linear-gradient(180deg, #eff6ff 0%, #ffffff 56%);
}
.billing-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
  margin-bottom: 12px;
}
.billing-headline {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  color: #0f172a;
  line-height: 1.3;
}
.billing-mode {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 999px;
  background: #dbeafe;
  color: #1d4ed8;
  font-size: 12px;
  font-weight: 700;
}
.billing-table {
  margin: 0 0 12px;
  background: #fff;
}
.billing-table th {
  background: #eff6ff;
}
.billing-examples {
  margin: 8px 0 12px;
  padding: 10px 12px;
  border-radius: 8px;
  background: #fff;
  border: 1px solid var(--line);
}
.billing-examples strong {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
}
.billing-examples ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 6px;
}
.billing-examples li {
  display: flex;
  justify-content: flex-start;
  align-items: baseline;
  gap: 16px;
  font-size: 13px;
  color: var(--muted);
}
.billing-examples code {
  color: #0f172a;
  font-weight: 700;
}
.billing-notes {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  font-size: 13px;
}

.error-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 12px 0 16px;
}
.error-chips code {
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  border-radius: 999px;
  padding: 4px 10px;
  color: #1d4ed8;
  font-size: 13px;
}

@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar {
    position: fixed;
    z-index: 20;
    transform: translateX(-100%);
    transition: transform .2s ease;
    width: min(88vw, 320px);
  }
  .sidebar.open { transform: translateX(0); box-shadow: 8px 0 24px rgba(15,23,42,.15); }
  .menu-btn { display: inline-block; }
  .main { padding: 16px 16px 48px; }
  table { display: block; overflow-x: auto; }
}