/* ============================================================
   React 学习站 · 设计系统
   视觉隐喻：原子轨道 / 组件粒子 —— React 青 × 深空蓝 × 电光紫
   ============================================================ */

:root {
  --bg: #0b1220;
  --bg-soft: #0e1830;
  --card: #101c34;
  --card-2: #0d1730;
  --text: #e7eefb;
  --muted: #93a6c8;
  --faint: #64748b;
  --border: rgba(148, 180, 233, 0.14);
  --border-strong: rgba(148, 180, 233, 0.26);
  --primary: #61dafb;
  --primary-soft: rgba(97, 218, 251, 0.12);
  --accent: #a78bfa;
  --amber: #fbbf24;
  --green: #34d399;
  --red: #f87171;
  --code-bg: #0a1224;
  --shadow: 0 14px 40px rgba(2, 8, 20, 0.5);
  --radius: 14px;
  --radius-sm: 9px;
  --mod: var(--primary);
  --mod-soft: rgba(97, 218, 251, 0.12);
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

[data-theme="light"] {
  --bg: #f3f7fc;
  --bg-soft: #eaf1f9;
  --card: #ffffff;
  --card-2: #f7fafd;
  --text: #122a47;
  --muted: #52678a;
  --faint: #8595ad;
  --border: rgba(18, 42, 71, 0.12);
  --border-strong: rgba(18, 42, 71, 0.22);
  --primary: #0891b2;
  --primary-soft: rgba(8, 145, 178, 0.1);
  --accent: #7c5cff;
  --amber: #b45309;
  --green: #059669;
  --red: #dc2626;
  --code-bg: #0b1220;
  --shadow: 0 12px 32px rgba(18, 42, 71, 0.1);
}

/* 模块色 */
[data-mod="basics"]   { --mod: #61dafb; --mod-soft: rgba(97, 218, 251, 0.12); }
[data-mod="core"]     { --mod: #a78bfa; --mod-soft: rgba(167, 139, 250, 0.13); }
[data-mod="adv"]      { --mod: #fbbf24; --mod-soft: rgba(251, 191, 36, 0.12); }
[data-mod="frontier"] { --mod: #34d399; --mod-soft: rgba(52, 211, 153, 0.12); }
[data-mod="overview"] { --mod: #61dafb; --mod-soft: rgba(97, 218, 251, 0.12); }
[data-mod="appendix"] { --mod: #94a3b8; --mod-soft: rgba(148, 163, 184, 0.13); }
[data-theme="light"][data-mod="basics"]   { --mod: #0e7490; }
[data-theme="light"][data-mod="core"]     { --mod: #6d28d9; }
[data-theme="light"][data-mod="adv"]      { --mod: #b45309; }
[data-theme="light"][data-mod="frontier"] { --mod: #047857; }

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
body::before {
  /* 原子轨道氛围底纹 */
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(1200px 700px at 85% -10%, rgba(97, 218, 251, 0.07), transparent 60%),
    radial-gradient(900px 600px at -10% 110%, rgba(167, 139, 250, 0.06), transparent 55%);
}
[data-theme="light"] body::before {
  background:
    radial-gradient(1200px 700px at 85% -10%, rgba(8, 145, 178, 0.06), transparent 60%),
    radial-gradient(900px 600px at -10% 110%, rgba(124, 92, 255, 0.05), transparent 55%);
}

a { color: var(--mod, var(--primary)); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
a.ext::after { content: "↗"; font-size: 0.72em; margin-left: 2px; opacity: 0.7; }

/* ---------------- 布局骨架 ---------------- */
.layout { display: flex; min-height: 100vh; position: relative; z-index: 1; }

.sidebar {
  width: 288px;
  flex: none;
  background: color-mix(in srgb, var(--bg-soft) 88%, transparent);
  border-right: 1px solid var(--border);
  padding: 20px 14px 28px;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  scrollbar-width: thin;
}
.sidebar::-webkit-scrollbar { width: 8px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 8px; }

.brand {
  display: flex; align-items: center; gap: 10px;
  padding: 6px 10px 14px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 14px;
}
.brand-orb {
  width: 34px; height: 34px; flex: none;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #bff3ff, var(--primary) 55%, #0e7490);
  box-shadow: 0 0 18px rgba(97, 218, 251, 0.5);
  animation: pulse 4s ease-in-out infinite;
}
@keyframes pulse { 50% { box-shadow: 0 0 30px rgba(97, 218, 251, 0.8); } }
.brand b { font-size: 16px; letter-spacing: 0.02em; display: block; line-height: 1.3; }
.brand span { font-size: 11px; color: var(--muted); }

.side-search { position: relative; margin: 0 4px 14px; }
.side-search input {
  width: 100%;
  background: var(--card);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 10px;
  padding: 9px 34px 9px 34px;
  font-size: 13.5px;
  outline: none;
  transition: border 0.2s, box-shadow 0.2s;
}
.side-search input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }
.side-search .icon { position: absolute; left: 11px; top: 50%; transform: translateY(-50%); opacity: 0.55; font-size: 13px; }
.side-search kbd {
  position: absolute; right: 8px; top: 50%; transform: translateY(-50%);
  font-family: var(--mono); font-size: 10.5px; color: var(--faint);
  border: 1px solid var(--border); border-radius: 5px; padding: 1px 5px;
}

.side-group { margin: 16px 4px 4px; }
.side-group > .label {
  font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--faint); padding: 0 10px 6px; font-weight: 600;
}
.side-link {
  display: flex; align-items: center; gap: 8px;
  padding: 7px 10px;
  border-radius: 9px;
  color: var(--muted);
  font-size: 13.5px;
  line-height: 1.45;
  transition: background 0.15s, color 0.15s;
}
.side-link:hover { background: var(--card); color: var(--text); text-decoration: none; }
.side-link.active { background: var(--primary-soft); color: var(--mod, var(--primary)); font-weight: 600; }
.side-link .tick { width: 15px; flex: none; text-align: center; font-size: 11px; color: var(--green); opacity: 0; }
.side-link.visited .tick { opacity: 1; }
.side-link .num { font-family: var(--mono); font-size: 10.5px; color: var(--faint); flex: none; }

.side-progress { margin: 18px 8px 0; padding-top: 14px; border-top: 1px solid var(--border); }
.side-progress .row { display: flex; justify-content: space-between; font-size: 12px; color: var(--muted); margin-bottom: 6px; }
.bar { height: 6px; border-radius: 99px; background: var(--card); overflow: hidden; border: 1px solid var(--border); }
.bar > i { display: block; height: 100%; width: 0; border-radius: 99px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transition: width 0.6s cubic-bezier(0.2, 0.8, 0.2, 1); }

/* ---------------- 主区 ---------------- */
.main { flex: 1; min-width: 0; padding: 34px clamp(20px, 5vw, 64px) 90px; }
.content { max-width: 830px; margin: 0 auto; }

.topbar {
  display: none;
  position: sticky; top: 0; z-index: 40;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 10px 16px;
  align-items: center; gap: 12px;
}
.topbar .burger {
  background: var(--card); border: 1px solid var(--border); color: var(--text);
  border-radius: 9px; width: 36px; height: 36px; font-size: 16px; cursor: pointer;
}
.topbar b { font-size: 14.5px; }
.topbar .spacer { flex: 1; }
.icon-btn {
  background: var(--card); border: 1px solid var(--border); color: var(--text);
  border-radius: 9px; width: 36px; height: 36px; font-size: 15px; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  transition: border 0.2s, transform 0.15s;
}
.icon-btn:hover { border-color: var(--primary); transform: translateY(-1px); }

/* 面包屑 + 标题 */
.crumb { font-size: 12.5px; color: var(--faint); margin-bottom: 10px; display: flex; gap: 8px; align-items: center; }
.crumb .dot { opacity: 0.5; }
h1.page-title {
  font-size: clamp(26px, 4vw, 36px);
  line-height: 1.25;
  margin: 0 0 14px;
  letter-spacing: -0.01em;
  background: linear-gradient(100deg, var(--text) 55%, var(--mod, var(--primary)));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.meta-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 26px; }
.chip {
  font-size: 12px; padding: 3px 10px; border-radius: 99px;
  border: 1px solid var(--border-strong); color: var(--muted);
  background: var(--card);
}
.chip.level { color: var(--mod, var(--primary)); border-color: color-mix(in srgb, var(--mod) 45%, transparent); background: var(--mod-soft); }

/* ---------------- 正文排版 ---------------- */
.doc { animation: fadeUp 0.5s cubic-bezier(0.2, 0.8, 0.2, 1); }
@keyframes fadeUp { from { opacity: 0; transform: translateY(10px); } }

.doc h2 {
  font-size: 20.5px;
  margin: 40px 0 12px;
  padding-left: 12px;
  border-left: 3px solid var(--mod, var(--primary));
  line-height: 1.4;
}
.doc h3 { font-size: 16.5px; margin: 26px 0 10px; color: var(--text); }
.doc p { margin: 10px 0; color: color-mix(in srgb, var(--text) 92%, var(--muted)); }
.doc strong { color: var(--text); }
.doc ul, .doc ol { padding-left: 22px; margin: 10px 0; }
.doc li { margin: 5px 0; }
.doc li::marker { color: var(--mod, var(--primary)); }
.doc hr { border: none; border-top: 1px dashed var(--border-strong); margin: 30px 0; }

.doc code {
  font-family: var(--mono);
  font-size: 0.855em;
  background: var(--card);
  border: 1px solid var(--border);
  padding: 1.5px 6px;
  border-radius: 6px;
  color: #8be9fd;
}
[data-theme="light"] .doc code { color: #0369a1; background: #eef5fb; }

.doc blockquote {
  margin: 14px 0;
  padding: 10px 16px;
  border-left: 3px solid var(--amber);
  background: color-mix(in srgb, var(--amber) 7%, transparent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--muted);
}
.doc blockquote p { margin: 4px 0; }

/* todo 清单 */
.doc ul.todo { list-style: none; padding-left: 4px; }
.doc ul.todo li { display: flex; gap: 9px; align-items: flex-start; padding: 4px 0; }
.doc ul.todo li::before {
  content: "";
  width: 15px; height: 15px; flex: none; margin-top: 5px;
  border: 1.5px solid var(--mod, var(--primary));
  border-radius: 4px; opacity: 0.75;
}

/* 表格 */
.table-wrap { overflow-x: auto; margin: 16px 0; border: 1px solid var(--border); border-radius: var(--radius-sm); }
.doc table { border-collapse: collapse; width: 100%; font-size: 14px; }
.doc th, .doc td { padding: 9px 14px; text-align: left; border-bottom: 1px solid var(--border); }
.doc th { background: var(--card); font-weight: 600; color: var(--mod, var(--primary)); white-space: nowrap; }
.doc tr:last-child td { border-bottom: none; }
.doc td code { white-space: nowrap; }

/* 代码块 */
pre.code {
  position: relative;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin: 16px 0;
  padding: 14px 16px;
  overflow-x: auto;
  box-shadow: var(--shadow);
}
pre.code code {
  background: none; border: none; padding: 0;
  font-family: var(--mono);
  font-size: 13px; line-height: 1.65;
  color: #dbe7f5;
  white-space: pre;
}
pre.code .lang-tag {
  position: absolute; top: 8px; right: 44px;
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em;
  color: #5b7295; text-transform: uppercase; pointer-events: none;
}
.copy-btn {
  position: absolute; top: 6px; right: 6px;
  background: rgba(255, 255, 255, 0.06);
  color: #9fb4d4;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 7px;
  font-size: 11px;
  padding: 3px 8px;
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.2s;
  font-family: var(--sans);
}
pre.code:hover .copy-btn { opacity: 1; }
.copy-btn:hover { color: #fff; border-color: rgba(255, 255, 255, 0.3); }

/* 语法高亮（构建期注入） */
.tok-kw { color: #c792ea; }
.tok-str { color: #a5e075; }
.tok-num { color: #f78c6c; }
.tok-com { color: #5c7099; font-style: italic; }

/* ---------------- 页脚导航 ---------------- */
.pn-nav { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 48px; }
.pn-card {
  display: block; padding: 14px 18px;
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: transform 0.18s, border-color 0.18s;
  color: var(--text);
}
.pn-card:hover { transform: translateY(-2px); border-color: var(--mod, var(--primary)); text-decoration: none; }
.pn-card.next { text-align: right; }
.pn-card .dir { font-size: 11.5px; color: var(--faint); display: block; margin-bottom: 3px; letter-spacing: 0.06em; }
.pn-card b { font-size: 14px; line-height: 1.45; display: block; }
.pn-card:only-child { grid-column: 1 / -1; }

.related { margin-top: 34px; padding: 16px 18px; background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); }
.related .label { font-size: 12px; color: var(--faint); margin-bottom: 10px; letter-spacing: 0.1em; }
.related .chips { display: flex; flex-wrap: wrap; gap: 8px; }
.rel-chip {
  font-size: 12.5px; padding: 4px 12px; border-radius: 99px;
  background: var(--mod-soft); color: var(--mod, var(--primary));
  border: 1px solid color-mix(in srgb, var(--mod) 35%, transparent);
}
.rel-chip:hover { text-decoration: none; filter: brightness(1.12); }

/* on-page 目录 */
.toc {
  margin-top: 34px;
  padding: 14px 18px;
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  font-size: 13px;
}
.toc .label { font-size: 12px; color: var(--faint); letter-spacing: 0.1em; margin-bottom: 8px; }
.toc a { color: var(--muted); display: block; padding: 2.5px 0; }
.toc a:hover { color: var(--mod, var(--primary)); text-decoration: none; }

/* ---------------- 首页 ---------------- */
.hero { text-align: center; padding: clamp(30px, 7vh, 70px) 0 40px; position: relative; }
.orbit-wrap { width: 120px; height: 120px; margin: 0 auto 26px; position: relative; }
.orbit { position: absolute; inset: 0; border: 1px dashed var(--border-strong); border-radius: 50%; }
.orbit.o2 { inset: -22px; animation: spin 14s linear infinite; }
.orbit.o3 { inset: 20px; animation: spin 9s linear infinite reverse; }
.orbit i {
  position: absolute; top: -4.5px; left: calc(50% - 4.5px);
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--primary); box-shadow: 0 0 10px var(--primary);
}
.orbit.o2 i { background: var(--accent); box-shadow: 0 0 10px var(--accent); }
.orbit.o3 i { background: var(--green); box-shadow: 0 0 10px var(--green); }
.orbit-wrap .core {
  position: absolute; inset: 42px; border-radius: 50%;
  background: radial-gradient(circle at 34% 32%, #d8f9ff, var(--primary) 52%, #0b7285);
  box-shadow: 0 0 34px rgba(97, 218, 251, 0.55);
  animation: pulse 4.5s ease-in-out infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.hero h1 {
  font-size: clamp(34px, 6vw, 56px);
  margin: 0 0 8px;
  letter-spacing: -0.02em;
  background: linear-gradient(105deg, #e7eefb 30%, var(--primary) 62%, var(--accent));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
[data-theme="light"] .hero h1 {
  background: linear-gradient(105deg, #122a47 30%, #0891b2 62%, #7c5cff);
  -webkit-background-clip: text; background-clip: text;
}
.hero .sub { color: var(--muted); max-width: 620px; margin: 0 auto 26px; font-size: 16.5px; }
.hero-cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 11px 24px; border-radius: 12px;
  font-size: 15px; font-weight: 600; cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.18s, box-shadow 0.18s;
}
.btn:hover { text-decoration: none; transform: translateY(-2px); }
.btn.primary {
  background: linear-gradient(120deg, var(--primary), #38bdf8);
  color: #04222e;
  box-shadow: 0 8px 24px rgba(97, 218, 251, 0.3);
}
.btn.ghost { background: var(--card); border-color: var(--border-strong); color: var(--text); }
.btn.ghost:hover { border-color: var(--primary); }

.stats { display: flex; gap: clamp(16px, 4vw, 42px); justify-content: center; margin: 40px 0 12px; flex-wrap: wrap; }
.stat b { font-size: 26px; font-family: var(--mono); color: var(--primary); display: block; text-align: center; }
.stat span { font-size: 12.5px; color: var(--faint); }

.mod-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; margin: 34px 0; }
.mod-card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
  position: relative; overflow: hidden;
  color: var(--text); display: block;
}
.mod-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); text-decoration: none; }
.mod-card::before {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 3px;
  background: linear-gradient(90deg, var(--mc), transparent);
}
.mod-card .k { font-family: var(--mono); font-size: 11px; color: var(--mc); letter-spacing: 0.12em; }
.mod-card h3 { margin: 6px 0 8px; font-size: 17px; }
.mod-card p { margin: 0; font-size: 13px; color: var(--muted); line-height: 1.6; }
.mod-card .n { position: absolute; right: 14px; top: 16px; font-family: var(--mono); font-size: 22px; opacity: 0.14; color: var(--mc); }
.mc-basics { --mc: #61dafb; } .mc-core { --mc: #a78bfa; }
.mc-adv { --mc: #fbbf24; } .mc-frontier { --mc: #34d399; }
.mc-overview { --mc: #61dafb; } .mc-appendix { --mc: #94a3b8; }

.feature-strip { display: flex; gap: 10px; flex-wrap: wrap; justify-content: center; margin-top: 22px; }
.feat {
  font-size: 12.5px; color: var(--muted);
  border: 1px solid var(--border); background: var(--card);
  padding: 5px 13px; border-radius: 99px;
}

/* ---------------- 地图页 ---------------- */
.map-mod { margin-bottom: 34px; }
.map-mod > h2 { display: flex; align-items: center; gap: 10px; font-size: 19px; margin-bottom: 14px; }
.map-mod > h2::before { content: ""; width: 10px; height: 10px; border-radius: 50%; background: var(--mc); box-shadow: 0 0 10px var(--mc); }
.map-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 12px; }
.map-card {
  background: var(--card); border: 1px solid var(--border); border-left: 3px solid var(--mc);
  border-radius: var(--radius-sm); padding: 12px 14px; display: block; color: var(--text);
  transition: transform 0.16s, border-color 0.16s;
}
.map-card:hover { transform: translateY(-2px); border-color: var(--mc); text-decoration: none; }
.map-card .top { display: flex; justify-content: space-between; align-items: baseline; gap: 8px; }
.map-card .id { font-family: var(--mono); font-size: 11px; color: var(--faint); }
.map-card b { font-size: 13.8px; line-height: 1.45; display: block; margin-top: 2px; }
.map-card .deps { margin-top: 8px; display: flex; flex-wrap: wrap; gap: 5px; }
.map-card .dep {
  font-size: 10.5px; font-family: var(--mono);
  color: var(--muted); border: 1px solid var(--border);
  padding: 1px 7px; border-radius: 99px;
}
.lvl-badge { font-size: 10px; padding: 1px 7px; border-radius: 99px; white-space: nowrap; }
.lvl-入门 { background: rgba(97, 218, 251, 0.14); color: #61dafb; }
.lvl-核心 { background: rgba(167, 139, 250, 0.15); color: #a78bfa; }
.lvl-进阶 { background: rgba(251, 191, 36, 0.14); color: #fbbf24; }
.lvl-前沿 { background: rgba(52, 211, 153, 0.14); color: #34d399; }
[data-theme="light"] .lvl-入门 { color: #0e7490; }
[data-theme="light"] .lvl-核心 { color: #6d28d9; }
[data-theme="light"] .lvl-进阶 { color: #b45309; }
[data-theme="light"] .lvl-前沿 { color: #047857; }

/* 阶段进度（roadmap） */
.stage-progress { margin: 10px 0 4px; display: flex; align-items: center; gap: 12px; font-size: 12.5px; color: var(--muted); }
.stage-progress .bar { flex: 1; }

/* ---------------- 搜索浮层 ---------------- */
.search-mask {
  position: fixed; inset: 0; z-index: 90;
  background: rgba(4, 10, 22, 0.62);
  backdrop-filter: blur(3px);
  display: none; align-items: flex-start; justify-content: center;
  padding: 9vh 16px 0;
}
.search-mask.open { display: flex; }
.search-panel {
  width: min(620px, 100%);
  background: var(--card); border: 1px solid var(--border-strong);
  border-radius: 16px; box-shadow: var(--shadow);
  overflow: hidden;
  animation: fadeUp 0.22s ease;
}
.search-panel .head { display: flex; align-items: center; gap: 10px; padding: 13px 16px; border-bottom: 1px solid var(--border); }
.search-panel input {
  flex: 1; background: none; border: none; outline: none;
  color: var(--text); font-size: 16px; font-family: var(--sans);
}
.search-panel .esc { font-size: 11px; color: var(--faint); border: 1px solid var(--border); border-radius: 5px; padding: 2px 7px; font-family: var(--mono); }
.search-results { max-height: 56vh; overflow-y: auto; padding: 8px; }
.search-results .empty { text-align: center; color: var(--faint); font-size: 13.5px; padding: 34px 0; }
.sr-item { display: block; padding: 10px 12px; border-radius: 10px; color: var(--text); }
.sr-item:hover, .sr-item.sel { background: var(--primary-soft); text-decoration: none; }
.sr-item .t { font-size: 14.5px; font-weight: 600; }
.sr-item .t em { color: var(--primary); font-style: normal; }
.sr-item .m { font-size: 11.5px; color: var(--faint); }
.sr-item .s { font-size: 12.5px; color: var(--muted); margin-top: 3px; line-height: 1.55;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

/* 抽屉（移动端） */
@media (max-width: 1023px) {
  .topbar { display: flex; }
  .sidebar {
    position: fixed; z-index: 60; left: 0; top: 0;
    transform: translateX(-105%);
    transition: transform 0.28s cubic-bezier(0.2, 0.8, 0.2, 1);
    box-shadow: var(--shadow);
    background: var(--bg-soft);
  }
  .sidebar.open { transform: translateX(0); }
  .main { padding-top: 24px; }
  .pn-nav { grid-template-columns: 1fr; }
  .pn-card.next { text-align: left; }
}
.drawer-mask { position: fixed; inset: 0; z-index: 55; background: rgba(4, 10, 22, 0.5); display: none; }
.drawer-mask.open { display: block; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.001s !important; transition-duration: 0.001s !important; }
  html { scroll-behavior: auto; }
}