:root {
  color-scheme: light;
  --bg: #f5f7f8;
  --surface: #ffffff;
  --surface-2: #edf2f4;
  --text: #142026;
  --muted: #5f717a;
  --line: #ced9de;
  --accent: #087984;
  --accent-soft: #d9f1f1;
  --code-bg: #edf2f4;
  --code-text: #9a4b15;
  --shadow: 0 18px 60px rgba(30, 54, 64, 0.14);
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0d1216;
  --surface: #141b20;
  --surface-2: #1e282f;
  --text: #eef4f8;
  --muted: #98aab4;
  --line: #30404a;
  --accent: #6edbd6;
  --accent-soft: #14383a;
  --code-bg: #0f1519;
  --code-text: #e6b45d;
  --shadow: 0 18px 60px rgba(0, 0, 0, 0.32);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  letter-spacing: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  display: grid;
  grid-template-columns: 280px minmax(220px, 520px) auto auto;
  gap: 14px;
  align-items: center;
  min-height: 68px;
  padding: 10px 18px;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  box-shadow: 0 0 0 1px var(--line);
}

.brand span {
  display: grid;
  gap: 2px;
}

.brand strong {
  font-size: 15px;
  line-height: 1.1;
}

.brand small {
  color: var(--muted);
  font-size: 12px;
}

.search {
  position: relative;
  display: grid;
  gap: 5px;
}

.search span {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--muted);
  font-size: 12px;
  pointer-events: none;
}

.search input {
  width: 100%;
  height: 42px;
  padding: 0 14px 0 50px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  font: inherit;
  outline: none;
}

.search input:focus {
  border-color: var(--accent);
}

.theme-toggle,
.nav-toggle {
  height: 42px;
  padding: 0 14px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  font: inherit;
  cursor: pointer;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 9px;
}

.theme-icon {
  width: 14px;
  height: 14px;
  border: 2px solid var(--accent);
  border-radius: 50%;
  background: linear-gradient(90deg, var(--accent) 50%, transparent 50%);
}

.nav-toggle {
  display: none;
}

.shell {
  display: grid;
  grid-template-columns: 290px minmax(0, 1fr) 240px;
  min-height: calc(100dvh - 68px);
}

.sidebar,
.toc {
  position: sticky;
  top: 68px;
  height: calc(100dvh - 68px);
  overflow: auto;
  padding: 22px 16px;
  border-right: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface) 76%, var(--bg));
}

.toc {
  border-right: 0;
  border-left: 1px solid var(--line);
}

.sidebar-section + .sidebar-section {
  margin-top: 28px;
}

.sidebar-section p,
.toc p {
  margin: 0 0 10px;
  color: var(--accent);
  font: 800 12px/1.2 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.sidebar nav,
.toc nav {
  display: grid;
  gap: 3px;
}

.sidebar a,
.toc a {
  display: block;
  padding: 8px 10px;
  color: var(--muted);
  border-left: 2px solid transparent;
  line-height: 1.35;
}

.sidebar a:hover,
.toc a:hover,
.sidebar a.active {
  color: var(--text);
  border-left-color: var(--accent);
  background: var(--accent-soft);
}

.toc a.h3 {
  padding-left: 24px;
  font-size: 13px;
}

.reader {
  position: relative;
  max-width: 980px;
  width: 100%;
  margin: 0 auto;
  padding: clamp(28px, 5vw, 64px);
}

.article {
  padding-bottom: 96px;
}

.article h1 {
  margin: 0 0 26px;
  font-size: clamp(38px, 6vw, 72px);
  line-height: 0.98;
  letter-spacing: 0;
}

.article h2 {
  margin: 52px 0 16px;
  padding-top: 10px;
  font-size: clamp(26px, 3vw, 38px);
  line-height: 1.08;
  letter-spacing: 0;
}

.article h3 {
  margin: 32px 0 12px;
  font-size: 21px;
}

.article h4 {
  margin: 24px 0 10px;
  font-size: 17px;
}

.article p,
.article li {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.78;
}

.article p {
  margin: 0 0 16px;
}

.article ul {
  margin: 0 0 20px;
  padding-left: 22px;
}

.article li + li {
  margin-top: 5px;
}

.article a {
  color: var(--accent);
  border-bottom: 1px solid color-mix(in srgb, var(--accent) 45%, transparent);
}

.article code {
  padding: 2px 5px;
  background: var(--code-bg);
  color: var(--code-text);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
}

.article pre {
  overflow: auto;
  margin: 18px 0 24px;
  padding: 18px;
  border: 1px solid var(--line);
  background: var(--code-bg);
  box-shadow: var(--shadow);
}

.article pre code {
  padding: 0;
  background: transparent;
  color: var(--text);
  font-size: 14px;
  line-height: 1.7;
}

.article table {
  width: 100%;
  margin: 18px 0 26px;
  border-collapse: collapse;
  border: 1px solid var(--line);
  background: var(--surface);
}

.article td {
  padding: 11px 13px;
  border: 1px solid var(--line);
  color: var(--muted);
  vertical-align: top;
}

.article tr:first-child td {
  color: var(--text);
  font-weight: 800;
  background: var(--surface-2);
}

.search-results {
  position: sticky;
  top: 86px;
  z-index: 10;
  margin-bottom: 22px;
  border: 1px solid var(--line);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.search-results a,
.search-results .empty {
  display: grid;
  gap: 4px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
}

.search-results a:last-child {
  border-bottom: 0;
}

.search-results strong {
  color: var(--text);
}

.search-results span,
.search-results .empty {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

.loading,
.error {
  padding: 22px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--muted);
}

@media (max-width: 1180px) {
  .shell {
    grid-template-columns: 270px minmax(0, 1fr);
  }

  .toc {
    display: none;
  }
}

@media (max-width: 820px) {
  .topbar {
    grid-template-columns: 1fr auto auto;
  }

  .search {
    grid-column: 1 / -1;
    order: 2;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
  }

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

  .sidebar {
    position: fixed;
    inset: 68px auto 0 0;
    z-index: 25;
    width: min(82vw, 320px);
    transform: translateX(-100%);
    transition: transform 180ms ease;
    box-shadow: var(--shadow);
  }

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

  .reader {
    padding: 28px 18px 64px;
  }

  .brand small,
  .theme-label {
    display: none;
  }
}