:root {
  --bg: #f6f8fa;
  --surface: #ffffff;
  --text: #24292f;
  --muted: #57606a;
  --border: #d0d7de;
  --accent: #0969da;
  --accent-hover: #0550ae;
  --sidebar-bg: #fafbfc;
  --code-bg: #f6f8fa;
  --radius: 8px;
  --shadow: 0 1px 3px rgba(27, 31, 36, 0.12);
  --max-width: 920px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html:not(.i18n-ready) body {
  visibility: hidden;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
  color: var(--accent-hover);
}

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

.sidebar {
  width: 260px;
  flex-shrink: 0;
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  padding: 24px 20px;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.sidebar .brand-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 4px;
}

.sidebar .brand-logo {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  flex-shrink: 0;
}

.sidebar .brand {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0;
}

.sidebar .brand-sub {
  font-size: 0.82rem;
  color: var(--muted);
  margin-bottom: 24px;
}

.sidebar nav a {
  display: block;
  padding: 7px 10px;
  border-radius: 6px;
  color: var(--muted);
  font-size: 0.92rem;
}

.sidebar nav a:hover {
  background: rgba(9, 105, 218, 0.08);
  color: var(--accent);
  text-decoration: none;
}

.sidebar nav a.active {
  background: rgba(9, 105, 218, 0.12);
  color: var(--accent);
  font-weight: 600;
}

.lang-switch {
  display: flex;
  gap: 6px;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.lang-switch span {
  font-size: 0.78rem;
  color: var(--muted);
  align-self: center;
  margin-right: 4px;
}

.lang-switch button {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--muted);
  font-size: 0.78rem;
  padding: 4px 10px;
  border-radius: 6px;
  cursor: pointer;
}

.lang-switch button.active {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(9, 105, 218, 0.08);
  font-weight: 600;
}

.lang-switch button:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.main {
  flex: 1;
  padding: 40px 48px 80px;
  max-width: calc(var(--max-width) + 96px);
}

.hero {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 40px;
  box-shadow: var(--shadow);
  margin-bottom: 32px;
}

.hero h1 {
  margin: 0 0 12px;
  font-size: 2rem;
  letter-spacing: -0.02em;
}

.hero .lead {
  font-size: 1.1rem;
  color: var(--muted);
  margin: 0 0 20px;
}

.hero .badge {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 999px;
  background: #ddf4ff;
  color: #0969da;
  margin-bottom: 16px;
}

section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 32px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

section h2 {
  margin: 0 0 16px;
  font-size: 1.35rem;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

section h3 {
  margin: 24px 0 10px;
  font-size: 1.05rem;
}

section p,
section li {
  color: var(--text);
}

section ul {
  padding-left: 1.25rem;
}

section li {
  margin-bottom: 8px;
}

.muted {
  color: var(--muted);
  font-size: 0.92rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 8px;
}

.feature-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  background: var(--code-bg);
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.feature-card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--muted);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 8px;
}

.contact-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  background: var(--surface);
}

.contact-card h3 {
  margin: 0 0 12px;
  font-size: 1rem;
  font-weight: 600;
}

.contact-email {
  margin: 0 0 12px;
  font-size: 1.05rem;
}

.contact-email a {
  font-weight: 500;
}

.contact-tip {
  margin: 0;
  font-size: 0.92rem;
  color: var(--muted);
  line-height: 1.6;
}

.section-intro {
  margin: -8px 0 16px;
}

.copy-block {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--code-bg);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.copy-content {
  margin: 0;
  font-family: inherit;
  font-size: 0.92rem;
  line-height: 1.65;
  color: var(--text);
  white-space: pre-wrap;
  word-break: break-word;
}

.copy-btn {
  align-self: flex-start;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
}

.copy-btn:hover {
  border-color: var(--accent);
  background: rgba(9, 105, 218, 0.08);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 12px 0;
}

th,
td {
  border: 1px solid var(--border);
  padding: 10px 12px;
  text-align: left;
}

th {
  background: var(--code-bg);
  font-weight: 600;
}

.footer {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--muted);
}

.menu-toggle {
  display: none;
}

@media (max-width: 768px) {
  .layout {
    flex-direction: column;
  }

  .sidebar {
    width: 100%;
    height: auto;
    position: relative;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding: 16px;
  }

  .main {
    padding: 24px 16px 48px;
  }

  .hero {
    padding: 24px 20px;
  }

  section {
    padding: 20px 18px;
  }

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