/* ==========================================================================
   Claude Code 源码笔记 · Anthropic 风格主题
   米白底 (#F0EEE6) · Claude 赤陶橙 (#D97757) · 衬线标题 / 无衬线正文
   ========================================================================== */

:root {
  /* 配色 */
  --bg: #F0EEE6;
  --bg-grad: #ECE9DE;
  --surface: #FFFFFF;
  --surface-soft: #FAF9F5;
  --surface-sunken: #EAE6DB;
  --ink: #1A1A17;
  --ink-soft: #55534C;
  --ink-faint: #8C897F;
  --accent: #D97757;
  --accent-strong: #C2553A;
  --accent-tint: #F4E4DB;
  --accent-tint-soft: #F8EEE7;
  --rule: #E2DDD0;
  --rule-soft: #ECE8DD;
  --code-bg: #21201C;
  --code-ink: #ECE6D7;
  --code-faint: #9D9885;

  /* 字体 */
  --font-serif: Georgia, "Times New Roman", "Songti SC", "STSong", "Noto Serif SC", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", "Fira Code", Menlo, Consolas,
    "Courier New", monospace;

  /* 尺度 */
  --measure: 880px;
  --nav-h: 64px;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 1px 2px rgba(26, 26, 23, 0.04), 0 6px 24px rgba(26, 26, 23, 0.06);
  --shadow-hover: 0 2px 6px rgba(26, 26, 23, 0.06), 0 14px 36px rgba(26, 26, 23, 0.10);
}

/* --- reset --- */
*, *::before, *::after { box-sizing: border-box; }
html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 16px);
  -webkit-text-size-adjust: 100%;
}
body {
  margin: 0;
  background: var(--bg);
  background-image: linear-gradient(180deg, var(--bg) 0%, var(--bg-grad) 100%);
  background-attachment: fixed;
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16.5px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
::selection { background: var(--accent-tint); color: var(--ink); }

/* --- 顶部导航 --- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  background: rgba(240, 238, 230, 0.82);
  backdrop-filter: saturate(140%) blur(12px);
  -webkit-backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--rule);
}
.nav-inner {
  max-width: 1080px;
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 15.5px;
  color: var(--ink);
  text-decoration: none;
  white-space: nowrap;
}
.brand .mark {
  width: 22px;
  height: 22px;
  border-radius: 6px;
  background: var(--accent);
  display: inline-block;
  position: relative;
  flex: none;
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.06);
}
.brand .mark::after {
  content: "";
  position: absolute;
  inset: 6px;
  border-radius: 2px;
  background: var(--bg);
}
.brand:hover { color: var(--accent-strong); }
.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  font-size: 14.5px;
}
.nav-links a {
  color: var(--ink-soft);
  text-decoration: none;
  transition: color 0.15s ease;
}
.nav-links a:hover { color: var(--accent-strong); }
.nav-links a.active { color: var(--accent-strong); font-weight: 600; }

/* --- 页面容器 --- */
.page {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 56px 24px 96px;
}
.page-wide { max-width: 1080px; }

/* --- 面包屑 --- */
.breadcrumb {
  font-size: 13.5px;
  color: var(--ink-faint);
  margin-bottom: 18px;
  letter-spacing: 0.01em;
}
.breadcrumb a { color: var(--ink-faint); text-decoration: none; }
.breadcrumb a:hover { color: var(--accent-strong); }
.breadcrumb .sep { margin: 0 8px; opacity: 0.6; }

/* --- 页头 --- */
.page-head { margin-bottom: 40px; }
.page-head h1 {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(30px, 5vw, 44px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  margin: 0 0 16px;
}
.page-head .lead {
  font-size: 18px;
  color: var(--ink-soft);
  margin: 0;
  max-width: 60ch;
}
.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent-strong);
  margin-bottom: 14px;
}

/* --- Hero（首页） --- */
.hero {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 72px 24px 24px;
  text-align: left;
}
.hero h1 {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(36px, 6.4vw, 60px);
  line-height: 1.1;
  letter-spacing: -0.015em;
  margin: 0 0 20px;
}
.hero .lead {
  font-size: clamp(18px, 2.4vw, 21px);
  color: var(--ink-soft);
  max-width: 62ch;
  margin: 0 0 28px;
}
.pill-row { display: flex; flex-wrap: wrap; gap: 10px; }
.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 13px;
  font-size: 13px;
  font-weight: 500;
  color: var(--ink-soft);
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 999px;
}
.pill .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }

/* --- 标题（正文内） --- */
.prose h2 {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 27px;
  line-height: 1.25;
  letter-spacing: -0.005em;
  margin: 56px 0 18px;
  padding-top: 14px;
  border-top: 1px solid var(--rule-soft);
  scroll-margin-top: calc(var(--nav-h) + 16px);
}
.prose h2:first-child { border-top: none; padding-top: 0; margin-top: 0; }
.prose h3 {
  font-weight: 650;
  font-size: 19.5px;
  line-height: 1.35;
  margin: 36px 0 12px;
  scroll-margin-top: calc(var(--nav-h) + 16px);
}
.prose h4 {
  font-weight: 650;
  font-size: 16.5px;
  color: var(--ink);
  margin: 26px 0 10px;
}
.anchor {
  color: var(--accent);
  text-decoration: none;
  margin-left: 10px;
  opacity: 0;
  font-weight: 400;
  transition: opacity 0.15s ease;
}
.prose h2:hover .anchor,
.prose h3:hover .anchor { opacity: 1; }

/* --- 正文 --- */
.prose { color: var(--ink); }
.prose p { margin: 0 0 18px; }
.prose a {
  color: var(--accent-strong);
  text-decoration: none;
  border-bottom: 1px solid rgba(194, 85, 58, 0.32);
  transition: border-color 0.15s ease;
}
.prose a:hover { border-bottom-color: var(--accent-strong); }
.prose strong { font-weight: 650; color: var(--ink); }
.prose ul, .prose ol { margin: 0 0 18px; padding-left: 1.45em; }
.prose li { margin: 7px 0; }
.prose li::marker { color: var(--accent); }
.prose ol li::marker { color: var(--ink-faint); font-variant-numeric: tabular-nums; }
.prose hr { border: none; border-top: 1px solid var(--rule); margin: 40px 0; }

/* --- 引用 / 提示框 --- */
.prose blockquote,
.callout {
  margin: 22px 0;
  padding: 16px 20px;
  background: var(--accent-tint-soft);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--ink-soft);
}
.prose blockquote p:last-child,
.callout p:last-child { margin-bottom: 0; }
.callout-title {
  display: block;
  font-weight: 650;
  color: var(--accent-strong);
  margin-bottom: 4px;
  font-size: 14px;
  letter-spacing: 0.02em;
}

/* --- 行内代码 --- */
.prose code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: var(--surface-sunken);
  color: var(--accent-strong);
  padding: 0.12em 0.42em;
  border-radius: 5px;
  word-break: break-word;
}

/* --- 代码块 --- */
.prose pre {
  margin: 22px 0;
  padding: 18px 20px;
  background: var(--code-bg);
  color: var(--code-ink);
  border-radius: var(--radius);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.65;
  box-shadow: var(--shadow);
}
.prose pre code {
  background: none;
  color: inherit;
  padding: 0;
  font-size: inherit;
  border-radius: 0;
}

/* --- 表格 --- */
.table-wrap {
  margin: 22px 0;
  overflow-x: auto;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}
.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14.5px;
}
.prose thead th {
  text-align: left;
  font-weight: 650;
  color: var(--ink);
  background: var(--surface-soft);
  padding: 12px 16px;
  border-bottom: 1px solid var(--rule);
  white-space: nowrap;
}
.prose tbody td {
  padding: 11px 16px;
  border-top: 1px solid var(--rule-soft);
  color: var(--ink-soft);
  vertical-align: top;
}
.prose tbody tr:first-child td { border-top: none; }
.prose tbody tr:hover td { background: var(--surface-soft); }
.prose td code, .prose th code { white-space: nowrap; }
.prose table.timeline td:nth-child(-n+2) {
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

/* --- 本页目录 (TOC) --- */
.toc {
  background: var(--surface-soft);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin-bottom: 44px;
}
.toc-title {
  font-size: 12.5px;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin: 0 0 12px;
}
.toc ol {
  margin: 0;
  padding: 0;
  list-style: none;
  columns: 2;
  column-gap: 32px;
}
.toc li { margin: 5px 0; break-inside: avoid; }
.toc a {
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 14.5px;
  border-bottom: none;
}
.toc a:hover { color: var(--accent-strong); }
.toc a .num { color: var(--accent); font-variant-numeric: tabular-nums; margin-right: 8px; }

/* --- 卡片网格（首页） --- */
.section-label {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 22px;
  margin: 64px 0 6px;
}
.section-desc { color: var(--ink-soft); margin: 0 0 24px; font-size: 15.5px; }
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(270px, 1fr));
  gap: 18px;
}
.card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: 22px 22px 20px;
  text-decoration: none;
  color: var(--ink);
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
  box-shadow: var(--shadow);
}
.card:hover {
  transform: translateY(-3px);
  border-color: var(--accent);
  box-shadow: var(--shadow-hover);
}
.card .card-index {
  font-size: 12.5px;
  font-weight: 650;
  color: var(--accent);
  letter-spacing: 0.04em;
  margin-bottom: 10px;
}
.card h3 { margin: 0 0 8px; font-size: 18px; font-weight: 650; line-height: 1.3; }
.card p { margin: 0; font-size: 14.5px; color: var(--ink-soft); line-height: 1.6; }
.card .card-go {
  margin-top: 14px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--accent-strong);
}

/* --- 信息块（首页 chain / list） --- */
.panel {
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: 26px 28px;
  margin: 28px 0;
  box-shadow: var(--shadow);
}
.panel h3 { margin-top: 0; }

/* --- 上一篇 / 下一篇 --- */
.page-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 64px;
  padding-top: 28px;
  border-top: 1px solid var(--rule);
}
.page-nav a {
  flex: 1;
  text-decoration: none;
  color: var(--ink);
  padding: 16px 20px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--surface);
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.page-nav a:hover { border-color: var(--accent); transform: translateY(-2px); }
.page-nav .dir { font-size: 12.5px; color: var(--ink-faint); display: block; margin-bottom: 4px; }
.page-nav .ttl { font-weight: 600; font-size: 15px; }
.page-nav .next { text-align: right; }
.page-nav .spacer { flex: 1; border: none; background: none; }

/* --- 页脚 --- */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 32px 24px;
  text-align: center;
  color: var(--ink-faint);
  font-size: 13.5px;
  line-height: 1.7;
}
.site-footer a { color: var(--ink-faint); text-decoration: none; }
.site-footer a:hover { color: var(--accent-strong); }

/* --- 响应式 --- */
@media (max-width: 768px) {
  body { font-size: 16px; }
  .nav-links { gap: 16px; font-size: 13.5px; }
  .nav-links .hide-sm { display: none; }
  .page { padding: 40px 18px 72px; }
  .hero { padding: 48px 18px 16px; }
  .toc ol { columns: 1; }
  .page-nav { flex-direction: column; }
  .page-nav .next { text-align: left; }
}
@media (max-width: 480px) {
  .nav-links { gap: 12px; }
}