:root {
  --header-h: 52px;
  --side-w: 232px;
  --green: #3c9d6c;
  --green-dark: #2f7d56;
  --ink: #333;
  --muted: #666;
  --line: #e5e5e5;
  --bg: #f6f6f6;
  --panel: #fff;
  --code-bg: #f5f2f0;
  --tip-bg: #f0f9f4;
  --warn-bg: #fff8e6;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "SF Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 12px);
}

body {
  margin: 0;
  color: var(--ink);
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.7;
  background: var(--bg);
}

a { color: var(--green-dark); text-decoration: none; }
a:hover { text-decoration: underline; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 0 1rem 0 1.1rem;
  background: var(--green);
  color: #fff;
}

.brand {
  color: #fff;
  font-weight: 700;
  font-size: 1.05rem;
  text-decoration: none;
  letter-spacing: 0.02em;
}

.header-nav {
  display: flex;
  gap: 0.85rem;
  margin-left: 0.5rem;
}

.header-nav a {
  color: rgba(255, 255, 255, 0.88);
  font-size: 0.92rem;
  text-decoration: none;
  padding: 0.2rem 0.35rem;
}

.header-nav a:hover,
.header-nav a.active {
  color: #fff;
  text-decoration: underline;
}

.header-nav a.nav-secondary {
  opacity: 0.78;
  font-size: 0.86rem;
}

.menu-btn {
  margin-left: auto;
  display: none;
  border: 1px solid rgba(255, 255, 255, 0.55);
  background: transparent;
  color: #fff;
  border-radius: 4px;
  padding: 0.25rem 0.6rem;
  font: inherit;
  cursor: pointer;
}

.shell {
  display: flex;
  max-width: 1180px;
  margin: 0 auto;
  min-height: calc(100vh - var(--header-h));
}

.sidebar {
  position: sticky;
  top: var(--header-h);
  align-self: flex-start;
  width: var(--side-w);
  flex: 0 0 var(--side-w);
  max-height: calc(100vh - var(--header-h));
  overflow: auto;
  background: var(--panel);
  border-right: 1px solid var(--line);
  padding: 1rem 0 2rem;
}

.side-title {
  margin: 0 0 0.55rem;
  padding: 0 1rem;
  font-size: 0.78rem;
  color: #999;
  letter-spacing: 0.06em;
}

.sidebar a {
  display: block;
  padding: 0.38rem 1rem;
  color: var(--ink);
  text-decoration: none;
  font-size: 0.88rem;
  border-left: 3px solid transparent;
}

.sidebar a:hover {
  background: #f3faf6;
  color: var(--green-dark);
}

.sidebar a.active {
  background: #eaf7f0;
  color: var(--green-dark);
  border-left-color: var(--green);
  font-weight: 600;
}

.content {
  flex: 1;
  min-width: 0;
  background: var(--panel);
  padding: 1.5rem 2rem 3rem;
  border-right: 1px solid var(--line);
}

.content h1 {
  margin: 0 0 0.75rem;
  font-size: 1.75rem;
  font-weight: 700;
  color: #222;
}

.lead {
  margin: 0 0 1.5rem;
  color: var(--muted);
  font-size: 0.98rem;
}

.content section {
  margin-bottom: 2.25rem;
  padding-top: 0.25rem;
}

.content h2 {
  margin: 0 0 0.85rem;
  padding-bottom: 0.45rem;
  font-size: 1.28rem;
  border-bottom: 1px solid var(--line);
  color: #222;
}

.content h3 {
  margin: 1.1rem 0 0.5rem;
  font-size: 1.05rem;
}

.content h3:first-child {
  margin-top: 0.4rem;
}

.content p,
.content ol,
.content ul {
  margin: 0.55rem 0;
}

.content ol,
.content ul {
  padding-left: 1.3rem;
}

.content code {
  font-family: var(--mono);
  font-size: 0.86em;
  background: var(--code-bg);
  padding: 0.08em 0.35em;
  border-radius: 3px;
}

.content pre {
  margin: 0.75rem 0;
  padding: 0.9rem 1rem;
  background: #2d2d2d;
  color: #f5f5f5;
  border-radius: 6px;
  overflow-x: auto;
  max-width: 100%;
}

.content pre code {
  background: none;
  color: inherit;
  padding: 0;
  font-size: 0.8rem;
  line-height: 1.55;
  white-space: pre;
  word-break: normal;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 0.75rem 0 1rem;
  font-size: 0.92rem;
}

th,
td {
  border: 1px solid var(--line);
  padding: 0.55rem 0.7rem;
  text-align: left;
  vertical-align: top;
}

th {
  background: #f7f7f7;
  font-weight: 600;
}

.tip,
.warn {
  margin: 0.9rem 0;
  padding: 0.7rem 0.9rem;
  border-radius: 6px;
  font-size: 0.92rem;
}

.tip {
  background: var(--tip-bg);
  border-left: 4px solid var(--green);
}

.warn {
  background: var(--warn-bg);
  border-left: 4px solid #e6a23c;
}

.btn {
  display: inline-block;
  margin-top: 0.4rem;
  padding: 0.45rem 0.9rem;
  background: var(--green);
  color: #fff !important;
  border-radius: 4px;
  text-decoration: none !important;
  font-size: 0.92rem;
}

.btn:hover {
  background: var(--green-dark);
}

.page-foot {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  color: #999;
  font-size: 0.88rem;
}

.side-mask {
  display: none;
}

@media (max-width: 860px) {
  .menu-btn { display: inline-block; }

  .sidebar {
    position: fixed;
    left: 0;
    top: var(--header-h);
    bottom: 0;
    z-index: 50;
    transform: translateX(-105%);
    transition: transform 0.2s ease;
    box-shadow: 4px 0 16px rgba(0, 0, 0, 0.12);
  }

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

  body.side-open .side-mask {
    display: block;
    position: fixed;
    inset: var(--header-h) 0 0 0;
    background: rgba(0, 0, 0, 0.35);
    z-index: 45;
  }

  .content {
    padding: 1.1rem 1rem 2.5rem;
    border-right: 0;
  }

  .header-nav { display: none; }
}