/* 主样式 — 单文件, 双主题由 tokens.css 变量驱动 */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font-family: var(--font-sans); line-height: 1.75; font-size: 16px;
}
a { color: var(--c-accent); text-decoration: none; }
a:hover { text-decoration: underline; }
:focus-visible { outline: 2px solid var(--c-accent); outline-offset: 2px; border-radius: 4px; }
.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--bg-elev); color: var(--fg); padding: 8px 14px; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }
.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

/* header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.header-inner { max-width: 1080px; margin: 0 auto; padding: 10px 20px; display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.brand { font-weight: 700; color: var(--fg); font-size: 17px; display: flex; align-items: center; gap: 8px; }
.brand:hover { text-decoration: none; }
.brand-mark { color: var(--c-primary); font-size: 18px; }
.main-nav { display: flex; gap: 4px; }
.main-nav a { color: var(--fg-muted); padding: 6px 10px; border-radius: var(--radius-sm); font-size: 14.5px; }
.main-nav a:hover { color: var(--fg); background: var(--bg-soft); text-decoration: none; }
.main-nav a[aria-current="page"] { color: var(--c-primary-ink); background: var(--bg-soft); font-weight: 600; }
[data-theme="dark"] .main-nav a[aria-current="page"] { color: var(--c-primary); }
.header-tools { margin-left: auto; display: flex; align-items: center; gap: 10px; }
.search-box { position: relative; }
#search-input {
  width: 210px; max-width: 52vw; padding: 7px 12px; font-size: 14px;
  border: 1px solid var(--border); border-radius: 999px; background: var(--bg-elev); color: var(--fg);
}
.search-results {
  position: absolute; right: 0; top: calc(100% + 6px); width: 340px; max-width: 86vw;
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden; z-index: 60;
}
.search-results ul { list-style: none; margin: 0; padding: 6px; max-height: 60vh; overflow: auto; }
.search-results a { display: block; padding: 8px 10px; border-radius: var(--radius-sm); color: var(--fg); }
.search-results a:hover, .search-results a:focus-visible { background: var(--bg-soft); text-decoration: none; }
.search-results .s-title { font-weight: 600; font-size: 14.5px; }
.search-results .s-meta { font-size: 12px; color: var(--fg-muted); }
.search-empty { padding: 12px; color: var(--fg-muted); font-size: 14px; }
.icon-btn {
  border: 1px solid var(--border); background: var(--bg-elev); color: var(--fg);
  width: 36px; height: 36px; border-radius: 50%; cursor: pointer; font-size: 15px;
}
.icon-btn:hover { border-color: var(--c-primary); }

/* hero */
.hero { padding: 54px 0 34px; background:
  radial-gradient(1200px 340px at 15% -20%, color-mix(in srgb, var(--c-primary) 16%, transparent), transparent),
  radial-gradient(900px 300px at 90% -30%, color-mix(in srgb, var(--c-accent) 14%, transparent), transparent);
  border-bottom: 1px solid var(--border); }
.hero h1 { font-size: 34px; margin: 0 0 12px; letter-spacing: 0.5px; }
.hero .kicker { color: var(--c-primary-ink); font-weight: 700; letter-spacing: 3px; font-size: 13px; margin-bottom: 10px; }
[data-theme="dark"] .hero .kicker { color: var(--c-primary); }
.hero p { max-width: 46em; color: var(--fg-muted); margin: 8px 0; }
.hero-actions { display: flex; gap: 12px; margin-top: 18px; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 10px 22px; border-radius: 999px; font-weight: 600; font-size: 15px;
  border: 1px solid var(--border); color: var(--fg); background: var(--bg-elev); cursor: pointer;
  transition: transform var(--dur) ease, box-shadow var(--dur) ease;
}
.btn-primary { background: var(--c-primary); border-color: var(--c-primary); color: #10230a; }
[data-theme="dark"] .btn-primary { color: #10230a; }
.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow); text-decoration: none; }
.stats-band { display: flex; gap: 26px; flex-wrap: wrap; align-items: center; margin-top: 26px; }
.ring-wrap { display: flex; align-items: center; gap: 14px; }
.ring circle { fill: none; stroke-width: 10; }
.ring-bg { stroke: var(--bg-soft); }
.ring-fg { stroke: var(--c-primary); stroke-linecap: round; transform: rotate(-90deg); transform-origin: 60px 60px; transition: stroke-dashoffset 400ms ease; }
.ring text { fill: var(--fg); font-size: 20px; font-weight: 700; }
.stat { min-width: 96px; }
.stat b { display: block; font-size: 22px; }
.stat span { color: var(--fg-muted); font-size: 13px; }

/* sections / cards */
.section { padding: 30px 0; }
.section > h2 { font-size: 22px; margin: 0 0 14px; }
.grid-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }
.module-card { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px 18px; box-shadow: var(--shadow); }
.module-card header { display: flex; justify-content: space-between; align-items: baseline; gap: 8px; margin-bottom: 8px; }
.module-card h2 { font-size: 16.5px; margin: 0; }
.mod-count { color: var(--fg-muted); font-size: 13px; white-space: nowrap; }
.kp-list { list-style: none; margin: 0; padding: 0; }
.kp-list li { display: flex; align-items: center; gap: 8px; padding: 3px 0; border-top: 1px dashed var(--border); }
.kp-list li:first-child { border-top: 0; }
.kp-list a { flex: 1; color: var(--fg); font-size: 14.5px; }
.dot { width: 9px; height: 9px; border-radius: 50%; border: 1.5px solid var(--fg-muted); flex: none; }
.dot.learning { background: var(--lv-adv); border-color: var(--lv-adv); }
.dot.mastered { background: var(--lv-ru); border-color: var(--lv-ru); }

/* badges & chips */
.badge { display: inline-block; padding: 2px 10px; border-radius: 999px; font-size: 12.5px; font-weight: 600; }
.badge.lv-入门 { color: var(--lv-ru); background: var(--lv-ru-bg); }
.badge.lv-核心 { color: var(--lv-core); background: var(--lv-core-bg); }
.badge.lv-进阶 { color: var(--lv-adv); background: var(--lv-adv-bg); }
.badge.lv-前沿 { color: var(--lv-fr); background: var(--lv-fr-bg); }
.tag-chip { display: inline-block; background: var(--bg-soft); color: var(--fg-muted); font-size: 12.5px; padding: 2px 10px; border-radius: 999px; margin: 2px 4px 2px 0; }

/* kp page */
.kp-layout { display: grid; grid-template-columns: minmax(0, 1fr) 264px; gap: 26px; padding-top: 26px; padding-bottom: 60px; }
.breadcrumb { font-size: 13.5px; color: var(--fg-muted); margin-bottom: 14px; }
.breadcrumb a { color: var(--fg-muted); }
.kp-article { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); padding: 30px 34px; box-shadow: var(--shadow); }
.kp-article h1 { font-size: 27px; line-height: 1.35; margin: 4px 0 10px; }
.kp-meta { display: flex; flex-wrap: wrap; gap: 8px 14px; align-items: center; color: var(--fg-muted); font-size: 13.5px; margin-bottom: 8px; }
.kp-article h2 { font-size: 19.5px; margin: 30px 0 8px; padding-top: 14px; border-top: 1px solid var(--border); }
.kp-article h2:first-of-type { border-top: 0; padding-top: 0; }
.kp-article h3 { font-size: 16.5px; margin: 20px 0 6px; }
.kp-article p { margin: 10px 0; }
.kp-article ul, .kp-article ol { padding-left: 1.4em; margin: 10px 0; }
.kp-article li { margin: 4px 0; }
.kp-article blockquote { margin: 12px 0; padding: 8px 16px; border-left: 3px solid var(--c-primary); background: var(--bg-soft); border-radius: 0 8px 8px 0; color: var(--fg-muted); }
.kp-ref { font-family: var(--font-mono); font-size: 0.92em; }
.table-wrap { overflow-x: auto; margin: 14px 0; }
table { border-collapse: collapse; width: 100%; font-size: 14px; }
th, td { border: 1px solid var(--border); padding: 7px 10px; text-align: left; vertical-align: top; }
th { background: var(--bg-soft); }
code { font-family: var(--font-mono); font-size: 0.9em; background: var(--bg-soft); padding: 1px 6px; border-radius: 5px; }
pre.diagram, pre.code, .formula { margin: 14px 0; border-radius: var(--radius-sm); overflow-x: auto; }
pre.diagram, pre.code { background: var(--code-bg); color: var(--code-fg); padding: 14px 16px; font-size: 13.2px; line-height: 1.6; }
pre.diagram, pre.code, .formula code, .formula { font-family: var(--font-mono); }
pre.code code, pre.diagram code { background: none; padding: 0; font-size: inherit; }
.formula { background: var(--bg-soft); border-left: 3px solid var(--c-accent); padding: 12px 16px; font-size: 14.5px; line-height: 1.9; }
.tok-c { color: #7d8f6d; font-style: italic; }
.tok-s { color: #e0b56a; }
.tok-p { color: #c98fd6; }
.tok-n { color: #8fd0e8; }
.tok-k { color: #9ad35f; font-weight: 600; }
.tok-t { color: #6fc7c2; }

/* pager + aside */
.pager { display: flex; justify-content: space-between; gap: 12px; margin-top: 18px; }
.pager a { flex: 1; background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 16px; color: var(--fg); font-size: 14px; }
.pager a:hover { text-decoration: none; border-color: var(--c-primary); }
.pager .p-label { color: var(--fg-muted); font-size: 12px; display: block; }
.pager .next { text-align: right; }
.kp-aside { display: flex; flex-direction: column; gap: 14px; }
.aside-card { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 16px; }
.aside-card h2 { font-size: 13.5px; margin: 0 0 8px; color: var(--fg-muted); text-transform: none; letter-spacing: 1px; }
.aside-card ul { list-style: none; margin: 0; padding: 0; font-size: 14px; }
.aside-card li { margin: 5px 0; }
.meta-list { color: var(--fg-muted); }
.meta-list b, .meta-list a { color: var(--fg); }
.prog-btns { display: flex; gap: 6px; }
.prog-btns button {
  flex: 1; padding: 7px 0; font-size: 13px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); background: var(--bg); color: var(--fg-muted); cursor: pointer;
}
.prog-btns button.active[data-val="learning"] { background: var(--lv-adv-bg); color: var(--lv-adv); border-color: var(--lv-adv); }
.prog-btns button.active[data-val="mastered"] { background: var(--lv-ru-bg); color: var(--lv-ru); border-color: var(--lv-ru); }
.prog-btns button:hover { border-color: var(--c-accent); }
.aside-actions { display: flex; gap: 8px; margin-top: 8px; }
.aside-actions button { flex: 1; font-size: 12.5px; padding: 6px 0; border-radius: var(--radius-sm); border: 1px solid var(--border); background: var(--bg); color: var(--fg-muted); cursor: pointer; }
.aside-actions button:hover { color: var(--fg); border-color: var(--c-accent); }

/* path page */
.path-min { display: flex; flex-direction: column; gap: 0; margin: 10px 0 26px; }
.path-step { display: flex; align-items: center; gap: 14px; padding: 11px 4px; border-bottom: 1px dashed var(--border); }
.path-step .step-no { font-family: var(--font-mono); color: var(--c-primary-ink); font-weight: 700; width: 28px; text-align: right; }
[data-theme="dark"] .path-step .step-no { color: var(--c-primary); }
.path-step a { font-weight: 600; }
.path-step .step-meta { color: var(--fg-muted); font-size: 13px; }
.phase-block { margin: 22px 0; }
.phase-block h2 { display: flex; align-items: center; gap: 10px; font-size: 18px; }
.phase-list { list-style: none; padding: 0; margin: 8px 0 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 8px; }
.phase-list li { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 9px 12px; font-size: 14px; display: flex; gap: 10px; align-items: center; }
.phase-list a { color: var(--fg); }
.progress-bar { height: 10px; border-radius: 999px; background: var(--bg-soft); overflow: hidden; margin: 10px 0 4px; }
.progress-bar > div { height: 100%; background: var(--c-primary); border-radius: 999px; transition: width 400ms ease; }

/* map page */
.map-scroll { overflow-x: auto; padding-bottom: 8px; }
.map-svg { min-width: 1720px; width: 100%; height: auto; }
.map-svg .map-edges path { fill: none; stroke: var(--border); stroke-width: 1.6; }
[data-theme="dark"] .map-svg .map-edges path { stroke: #3a4630; }
.map-svg rect { fill: var(--bg-elev); stroke: var(--fg-muted); stroke-width: 1; }
.map-svg rect.lv-入门 { stroke: var(--lv-ru); }
.map-svg rect.lv-核心 { stroke: var(--lv-core); }
.map-svg rect.lv-进阶 { stroke: var(--lv-adv); }
.map-svg rect.lv-前沿 { stroke: var(--lv-fr); }
.map-svg a:hover rect { stroke-width: 2.4; }
.map-svg text { fill: var(--fg); font-family: var(--font-sans); }
.map-svg .map-mod { font-weight: 700; font-size: 14px; }
.map-svg .map-id { font-family: var(--font-mono); font-size: 11px; fill: var(--fg-muted); }
.map-svg .map-title { font-size: 13px; }

/* glossary */
.glossary-group { margin: 24px 0; }
.glossary-group h2 { font-size: 17px; margin-bottom: 8px; }
.glossary-table td:first-child { font-weight: 600; white-space: nowrap; }
.glossary-table td:nth-child(2) { color: var(--fg-muted); font-family: var(--font-mono); font-size: 13px; }

/* footer */
.site-footer { border-top: 1px solid var(--border); color: var(--fg-muted); font-size: 13px; padding: 22px 0 34px; margin-top: 30px; }

@media (max-width: 900px) {
  .kp-layout { grid-template-columns: 1fr; }
  .kp-aside { order: 2; }
  .kp-article { padding: 22px 20px; }
  .hero h1 { font-size: 27px; }
}
@media (max-width: 640px) {
  .header-inner { gap: 10px; }
  .main-nav { order: 3; width: 100%; }
  #search-input { width: 150px; }
}
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}