/* 多智能体系统 · 学习站样式（零依赖，配合 tokens.css 使用） */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 20px; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; border-radius: 4px; }

/* 跳过导航 */
.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--primary); color: var(--on-primary);
  padding: 8px 16px; border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus { left: 0; }

/* 头部 */
.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 { display: flex; align-items: center; gap: 18px; min-height: 58px; flex-wrap: wrap; padding-top: 6px; padding-bottom: 6px; }
.brand { display: inline-flex; align-items: baseline; gap: 8px; font-weight: 700; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand-mark {
  width: 12px; height: 12px; align-self: center; border-radius: 3px;
  background: linear-gradient(135deg, var(--primary) 0 50%, var(--accent) 50% 100%);
  transform: rotate(45deg);
}
.brand-sub { font-weight: 500; color: var(--muted); font-size: 13px; }
.site-nav { display: flex; gap: 4px; }
.site-nav a {
  padding: 6px 10px; border-radius: var(--radius-sm);
  color: var(--muted); font-size: 14px;
}
.site-nav a:hover { color: var(--text); background: var(--surface-2); text-decoration: none; }
.header-tools { margin-left: auto; display: flex; align-items: center; gap: 10px; }

/* 搜索 */
.search-box { position: relative; }
.search-box input {
  width: 230px; max-width: 56vw;
  padding: 7px 12px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); background: var(--surface);
  color: var(--text); font-size: 14px; font-family: inherit;
}
.search-box input:focus { border-color: var(--focus); box-shadow: var(--shadow-focus); outline: none; }
.search-results {
  position: absolute; right: 0; top: calc(100% + 6px); width: 360px; max-width: 80vw;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden; z-index: 60;
}
.search-results a {
  display: block; padding: 9px 14px; color: var(--text); border-bottom: 1px solid var(--border);
}
.search-results a:last-child { border-bottom: 0; }
.search-results a:hover, .search-results a.active { background: var(--surface-2); text-decoration: none; }
.search-results .sr-title { font-weight: 600; font-size: 14px; }
.search-results .sr-meta { color: var(--muted); font-size: 12px; margin-left: 6px; }
.search-empty { padding: 12px 14px; color: var(--muted); font-size: 14px; }
.icon-btn {
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  border-radius: var(--radius-sm); padding: 7px 12px; font-size: 13px; cursor: pointer;
  font-family: inherit;
}
.icon-btn:hover { border-color: var(--focus); }

/* 通用组件 */
.card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px 22px; box-shadow: var(--shadow);
}
.btn {
  display: inline-block; border: 1px solid var(--border); cursor: pointer;
  background: var(--surface); color: var(--text);
  padding: 8px 16px; border-radius: var(--radius-sm);
  font-size: 14px; font-family: inherit; font-weight: 500;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.btn:hover { border-color: var(--focus); text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--primary); border-color: var(--primary); color: var(--on-primary); }
.btn-primary:hover { background: var(--primary-strong); border-color: var(--primary-strong); }
.btn-ghost { background: transparent; }

.chip {
  display: inline-flex; align-items: center; gap: 6px;
  border: 1px solid var(--border); background: var(--surface-2);
  border-radius: 999px; padding: 3px 12px; font-size: 13px; color: var(--text);
}
.chip:hover { text-decoration: none; border-color: var(--focus); }
.chip-id { font-family: var(--font-mono); font-size: 12px; color: var(--muted); }
.chip-row { display: flex; flex-wrap: wrap; gap: 8px; }
.module-chip { color: var(--muted); }
.tag { color: var(--accent); font-size: 13px; margin-right: 8px; }

.kp-level {
  display: inline-block; font-size: 12px; font-weight: 600;
  padding: 2px 10px; border-radius: 999px; border: 1px solid currentColor;
  background: color-mix(in srgb, currentColor 10%, transparent);
}
.lv-intro { color: var(--lv-intro); }
.lv-core { color: var(--lv-core); }
.lv-adv { color: var(--lv-adv); }
.lv-frontier { color: var(--lv-frontier); }
.kp-min { color: var(--muted); font-size: 12px; white-space: nowrap; }

/* 首页 */
.hero { padding: 52px 0 8px; }
.hero-eyebrow { color: var(--accent); font-weight: 600; letter-spacing: 0.08em; font-size: 13px; margin: 0 0 6px; }
.hero h1 { font-size: 40px; line-height: 1.2; margin: 0 0 10px; letter-spacing: 0.01em; }
.tagline { color: var(--muted); font-size: 17px; margin: 0 0 14px; font-weight: 500; }
.hero-intro { max-width: 62ch; color: var(--muted); font-size: 15px; margin: 0 0 22px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 30px; }

.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin: 10px 0 22px; }
.stat {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 14px 10px; text-align: center; box-shadow: var(--shadow);
}
.stat strong { display: block; font-size: 26px; color: var(--primary); }
.stat span { color: var(--muted); font-size: 13px; }

.progress-panel { margin: 0 0 26px; }
.progress-head { display: flex; align-items: baseline; gap: 10px; margin-bottom: 10px; }
.progress-head strong { font-size: 22px; color: var(--primary); }
.progress-detail { color: var(--muted); font-size: 13px; }
.bar { height: 10px; border-radius: 999px; background: var(--surface-2); overflow: hidden; }
.bar span {
  display: block; height: 100%; width: 0;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 999px; transition: width var(--dur) var(--ease);
}
.progress-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 12px; align-items: center; }

.module-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 40px; }
.module-card { border-top: 3px solid var(--m-accent, var(--primary)); }
.module-card-head { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; flex-wrap: wrap; }
.module-card h3 { margin: 0; font-size: 17px; }
.module-meta { color: var(--muted); font-size: 13px; }
.module-kp-list { list-style: none; margin: 12px 0 0; padding: 0; }
.module-kp-list li + li { border-top: 1px dashed var(--border); }
.module-kp-list a {
  display: flex; align-items: center; gap: 10px; padding: 8px 2px; color: var(--text);
}
.module-kp-list a:hover { text-decoration: none; }
.module-kp-list a:hover .kp-title { color: var(--primary); }
.module-kp-list .kp-title { flex: 1; font-size: 14px; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* 页头 */
.page-head { padding: 34px 0 8px; }
.page-head h1 { margin: 0 0 6px; font-size: 30px; }
.page-sub { color: var(--muted); margin: 0 0 18px; }

/* 学习路径 */
.minimal-path { margin-bottom: 26px; }
.stage-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; flex-wrap: wrap; margin-bottom: 6px; }
.stage-head h2, .stage-head h3 { margin: 0; font-size: 18px; display: flex; align-items: center; gap: 10px; }
.stage-desc { color: var(--muted); font-size: 14px; margin: 0 0 14px; }
.min-list { list-style: none; margin: 0; padding: 0; counter-reset: minpath; }
.min-item {
  display: flex; align-items: center; gap: 12px; padding: 9px 2px;
  border-top: 1px dashed var(--border); counter-increment: minpath;
}
.min-item::before {
  content: counter(minpath); font-family: var(--font-mono); font-size: 12px;
  color: var(--muted); width: 20px; text-align: right;
}
.min-item a { flex: 1; color: var(--text); font-size: 14.5px; min-width: 0; }
.min-item a:hover { color: var(--primary); text-decoration: none; }
.min-dot {
  width: 12px; height: 12px; border-radius: 50%;
  border: 2px solid var(--border); background: transparent; flex: none;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.min-item[data-state="learning"] .min-dot { border-color: var(--lv-adv); background: color-mix(in srgb, var(--lv-adv) 45%, transparent); }
.min-item[data-state="done"] .min-dot { border-color: var(--lv-intro); background: var(--lv-intro); }
.stage-card { margin-bottom: 16px; }
.stage-list { list-style: none; margin: 10px 0 0; padding: 0; }
.stage-list li { border-top: 1px dashed var(--border); }
.stage-list a { display: flex; gap: 10px; align-items: center; padding: 8px 2px; color: var(--text); font-size: 14.5px; }
.stage-list a:hover { color: var(--primary); text-decoration: none; }
.stage-list .kp-title { flex: 1; min-width: 0; }
.reading-card { margin: 22px 0 44px; }

/* 知识地图 */
.map-card { margin-bottom: 20px; }
.map-legend { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-bottom: 12px; }
.legend-note { color: var(--muted); font-size: 13px; }
.map-scroll { overflow-x: auto; padding-bottom: 8px; }
.map-svg { max-width: none; display: block; }
.map-col-head text { fill: var(--text); font-size: 15px; font-weight: 700; }
.map-col-head .map-col-sub { fill: var(--muted); font-size: 12px; font-weight: 400; }
.edge { fill: none; stroke: var(--border); stroke-width: 1.6; marker-end: url(#arrow); }
.edge-back { stroke-dasharray: 5 4; }
.edge-arrow { fill: var(--muted); }
.map-node rect {
  fill: var(--surface); stroke: var(--border); stroke-width: 1.4;
  transition: stroke var(--dur) var(--ease);
}
.map-node:hover rect { stroke: var(--focus); }
.map-node text { pointer-events: none; }
.map-node-id { font-family: var(--font-mono); font-size: 11px; fill: var(--muted); }
.map-node-title { font-size: 12.5px; fill: var(--text); font-weight: 600; }
.map-node.lv-intro rect { stroke: color-mix(in srgb, var(--lv-intro) 55%, var(--border)); }
.map-node.lv-core rect { stroke: color-mix(in srgb, var(--lv-core) 55%, var(--border)); }
.map-node.lv-adv rect { stroke: color-mix(in srgb, var(--lv-adv) 55%, var(--border)); }
.map-node.lv-frontier rect { stroke: color-mix(in srgb, var(--lv-frontier) 55%, var(--border)); }

/* 知识点页 */
.breadcrumb { padding: 26px 0 0; color: var(--muted); font-size: 13.5px; display: flex; gap: 8px; flex-wrap: wrap; }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--primary); }
.kp-article { padding-bottom: 30px; }
.kp-header { padding: 14px 0 4px; }
.kp-header-top { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.kp-header h1 { font-size: 28px; line-height: 1.3; margin: 12px 0 6px; }
.kp-tags { margin: 0; }
.kp-relations { margin: 18px 0; }
.rel-title { font-size: 13px; color: var(--muted); margin: 0 0 8px; font-weight: 600; letter-spacing: 0.05em; }

/* 正文排版：直觉→定义→原理→例子→练习→延伸 */
.kp-body { font-size: 15.5px; }
.kp-body h2 {
  font-size: 19px; margin: 30px 0 10px; padding-top: 14px;
  border-top: 1px solid var(--border);
}
.kp-body h2:first-child { border-top: 0; margin-top: 8px; padding-top: 0; }
.kp-body h3 { font-size: 16px; margin: 20px 0 8px; }
.kp-body p { margin: 10px 0; }
.kp-body ul, .kp-body ol { margin: 10px 0; padding-left: 22px; }
.kp-body li { margin: 5px 0; }
.kp-body blockquote {
  margin: 14px 0; padding: 10px 16px; border-left: 3px solid var(--accent);
  background: color-mix(in srgb, var(--accent) 7%, transparent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0; color: var(--muted);
}
.kp-body code {
  font-family: var(--font-mono); font-size: 0.86em;
  background: var(--surface-2); border: 1px solid var(--border);
  padding: 1px 5px; border-radius: 5px;
}
.code-block { margin: 14px 0; }
.code-block pre {
  margin: 0; padding: 14px 16px; overflow-x: auto;
  background: var(--code-bg); border: 1px solid var(--code-border);
  border-radius: var(--radius-sm); font-size: 13px; line-height: 1.6;
}
.code-block code { font-family: var(--font-mono); background: none; border: 0; padding: 0; color: var(--text); }
.tok-k { color: var(--tok-k); font-weight: 600; }
.tok-s { color: var(--tok-s); }
.tok-c { color: var(--tok-c); font-style: italic; }
.tok-n { color: var(--tok-n); }
.table-wrap { overflow-x: auto; margin: 14px 0; border: 1px solid var(--border); border-radius: var(--radius-sm); }
.kp-body table, .glossary-table { border-collapse: collapse; width: 100%; font-size: 14px; }
.kp-body th, .kp-body td, .glossary-table th, .glossary-table td {
  border-bottom: 1px solid var(--border); padding: 8px 12px; text-align: left; vertical-align: top;
}
.kp-body thead th, .glossary-table thead th {
  background: var(--surface-2); font-size: 13px; color: var(--muted); white-space: nowrap;
}
.kp-body tbody tr:last-child th, .kp-body tbody tr:last-child td { border-bottom: 0; }
.kp-body tbody tr:nth-child(even) { background: color-mix(in srgb, var(--surface-2) 45%, transparent); }

/* 知识点进度与翻页 */
.kp-progress { margin-top: 26px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.kp-pager { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 22px 0 10px; }
.pager {
  border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 16px;
  background: var(--surface); color: var(--text); display: block;
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.pager:hover { border-color: var(--focus); text-decoration: none; transform: translateY(-1px); }
.pager.placeholder { visibility: hidden; }
.pager.next { text-align: right; }
.pager-label { display: block; color: var(--muted); font-size: 12px; margin-bottom: 4px; }
.pager-title { font-size: 14px; font-weight: 600; }

/* 术语表 */
.search-box.standalone { margin: 0 0 18px; }
.search-box.standalone input { width: 100%; max-width: 420px; }
.glossary-group { margin-bottom: 18px; }
.glossary-group h2 { margin: 0 0 12px; font-size: 18px; }
.glossary-table tbody th { font-weight: 600; white-space: nowrap; }
.gl-en { color: var(--muted); font-family: var(--font-mono); font-size: 12.5px; white-space: nowrap; }

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

/* 响应式 */
@media (max-width: 860px) {
  .module-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .kp-pager { grid-template-columns: 1fr; }
  .pager.next { text-align: left; }
  .hero h1 { font-size: 32px; }
}
@media (max-width: 640px) {
  .header-inner { gap: 10px; }
  .search-box input { width: 150px; }
  .site-nav a { padding: 6px 7px; font-size: 13px; }
  .brand-sub { display: none; }
}

/* 动效降级 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
    scroll-behavior: auto !important;
  }
}