/* 桥式手册 — 全站样式（Apple 风格 · 深色默认 + 浅色主题）
   主题机制：所有颜色走 :root 语义变量；:root[data-theme="light"] 覆盖为浅色。
   切换由 site.js 修改 <html data-theme> 并广播 themechange 事件（魔方/展开图会重绘）。 */
:root {
  color-scheme: dark;
  --bg: #0a0a0b;
  --card: #1a1a1d;
  --ink: #f5f5f7;
  --muted: #a1a1a6;
  --line: rgba(255, 255, 255, 0.10);
  --line-strong: rgba(255, 255, 255, 0.18);
  --hairline: 1px solid rgba(255, 255, 255, 0.07);
  --accent: #0a84ff;
  --accent-hover: #409cff;
  --accent-soft: rgba(10, 132, 255, 0.15);
  --ok: #4cd964;
  --warn: #ff9f0a;
  --radius: 18px;
  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.5), 0 12px 32px rgba(0, 0, 0, 0.4);
  /* 结构性颜色 */
  --header-bg: rgba(14, 14, 16, 0.78);
  --nav-link: #b8b8bd;
  --soft: rgba(255, 255, 255, 0.08);
  --soft-hover: rgba(255, 255, 255, 0.14);
  --soft-strong: rgba(255, 255, 255, 0.11);
  --pill-active-bg: #48484c;
  --pill-active-ink: #ffffff;
  --pill-active-shadow: none;
  --chip: rgba(255, 255, 255, 0.07);
  --th-bg: rgba(255, 255, 255, 0.045);
  --row-hover: rgba(255, 255, 255, 0.03);
  --scene-bg: rgba(255, 255, 255, 0.04);
  --slider-track: rgba(255, 255, 255, 0.18);
  --select-bg: #2a2a2e;
  --mask-bg: rgba(0, 0, 0, 0.55);
  --ob-mask-bg: rgba(8, 8, 10, 0.78);
  --opt-hover-bg: rgba(255, 255, 255, 0.09);
  --dot-border: rgba(255, 255, 255, 0.25);
  --footer-underline: rgba(255, 255, 255, 0.3);
  --alg-primary-bg: rgba(255, 214, 10, 0.13);
  --alg-primary-ring: rgba(255, 214, 10, 0.28);
  --btn-shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
  --selection: rgba(10, 132, 255, 0.35);
  --tag-ink: #7cb8ff;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "SF Pro SC", "Segoe UI", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Code", Consolas, "Courier New", monospace;
}
:root[data-theme="light"] {
  color-scheme: light;
  --bg: #f5f5f7;
  --card: #ffffff;
  --ink: #1d1d1f;
  --muted: #6e6e73;
  --line: rgba(0, 0, 0, 0.08);
  --line-strong: rgba(0, 0, 0, 0.14);
  --hairline: 1px solid rgba(0, 0, 0, 0.05);
  --accent: #0071e3;
  --accent-hover: #0077ed;
  --accent-soft: rgba(0, 113, 227, 0.09);
  --ok: #1d8a41;
  --warn: #b25000;
  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.04), 0 10px 30px rgba(0, 0, 0, 0.05);
  --header-bg: rgba(251, 251, 253, 0.78);
  --nav-link: #424245;
  --soft: rgba(0, 0, 0, 0.055);
  --soft-hover: rgba(0, 0, 0, 0.1);
  --soft-strong: rgba(0, 0, 0, 0.075);
  --pill-active-bg: #ffffff;
  --pill-active-ink: #1d1d1f;
  --pill-active-shadow: 0 1px 4px rgba(0, 0, 0, 0.14);
  --chip: #f5f5f7;
  --th-bg: #fafafa;
  --row-hover: rgba(0, 0, 0, 0.018);
  --scene-bg: rgba(0, 0, 0, 0.035);
  --slider-track: rgba(0, 0, 0, 0.15);
  --select-bg: #ffffff;
  --mask-bg: rgba(0, 0, 0, 0.35);
  --ob-mask-bg: rgba(245, 245, 247, 0.82);
  --opt-hover-bg: #ffffff;
  --dot-border: rgba(0, 0, 0, 0.15);
  --footer-underline: rgba(0, 0, 0, 0.25);
  --alg-primary-bg: #fff8e6;
  --alg-primary-ring: rgba(180, 130, 0, 0.16);
  --btn-shadow: 0 1px 2px rgba(0, 60, 130, 0.2);
  --selection: rgba(0, 113, 227, 0.18);
  --tag-ink: #0062cc;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: var(--font);
  line-height: 1.75; font-size: 15.5px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background 0.3s ease, color 0.3s ease;
}
a { color: var(--accent); text-decoration: none; transition: color 0.18s; }
a:hover { color: var(--accent-hover); text-decoration: none; }
::selection { background: var(--selection); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 6px; }

/* ---------- 模式过滤 ---------- */
body[data-mode="basic"] [data-track="advance"] { display: none !important; }
body[data-mode="advance"] [data-track="basic"] { display: none !important; }
body[data-mode="advance"] .site-header nav a[data-nav="basics"] { display: none; }

/* ---------- 头部：磨砂玻璃 ---------- */
.site-header {
  background: var(--header-bg);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
  color: var(--ink);
  padding: 9px 22px;
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  position: sticky; top: 0; z-index: 50;
  transition: background 0.3s ease;
}
.site-header .logo { font-weight: 700; font-size: 17px; letter-spacing: -0.01em; color: var(--ink); }
.site-header .logo em { color: var(--accent); font-style: normal; }
.site-header nav { display: flex; gap: 2px; flex-wrap: wrap; }
.site-header nav a {
  color: var(--nav-link); padding: 6px 13px; border-radius: 980px; font-size: 14px; font-weight: 500;
  transition: background 0.18s, color 0.18s;
}
.site-header nav a:hover { background: var(--soft); color: var(--ink); }
.site-header nav a.active { background: var(--soft-strong); color: var(--ink); }
.site-header .spacer { flex: 1; }
.mode-seg {
  display: flex; gap: 2px; background: var(--soft);
  border-radius: 980px; padding: 2px;
}
.mode-seg button {
  border: 0; background: transparent; padding: 4px 13px; border-radius: 980px;
  font-size: 13px; font-family: inherit; color: var(--nav-link); cursor: pointer;
  transition: background 0.18s, color 0.18s, box-shadow 0.18s;
}
.mode-seg button:hover { color: var(--ink); }
.mode-seg button.active { background: var(--pill-active-bg); color: var(--pill-active-ink); font-weight: 600; box-shadow: var(--pill-active-shadow); }
.scheme-btn {
  background: var(--soft); color: var(--ink); border: 0;
  padding: 6px 14px; border-radius: 980px; cursor: pointer; font-size: 13.5px; font-family: inherit;
  transition: background 0.18s;
}
.scheme-btn:hover { background: var(--soft-hover); }

/* ---------- 隐藏章节提示条 ---------- */
.track-notice {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  background: var(--accent-soft); color: var(--ink);
  border-radius: 14px; padding: 10px 16px; margin: 0 0 18px; font-size: 14px;
}
.track-notice button {
  border: 0; background: var(--accent); color: #fff; font-family: inherit;
  border-radius: 980px; padding: 4px 14px; font-size: 13px; cursor: pointer;
  transition: background 0.18s;
}
.track-notice button:hover { background: var(--accent-hover); }

/* ---------- 排版 ---------- */
main { max-width: 1080px; margin: 0 auto; padding: 34px 22px 80px; }
h1 { font-size: 30px; letter-spacing: -0.02em; margin: 8px 0 8px; line-height: 1.25; text-wrap: balance; }
h2 { font-size: 22px; letter-spacing: -0.015em; margin: 40px 0 14px; line-height: 1.3; }
h3 { font-size: 17px; letter-spacing: -0.01em; margin: 22px 0 8px; }
.lead { color: var(--muted); font-size: 16.5px; margin: 6px 0 10px; max-width: 68ch; text-wrap: pretty; }

.card {
  background: var(--card); border-radius: var(--radius);
  border: var(--hairline);
  padding: 20px 24px; margin: 16px 0;
  box-shadow: var(--shadow-card);
  transition: background 0.3s ease, border-color 0.3s ease;
}
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.grid3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.grid4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
@media (max-width: 860px) { .grid2, .grid3, .grid4 { grid-template-columns: 1fr; } }

/* ---------- 表格：发丝线 + 圆角容器 ---------- */
table {
  border-collapse: separate; border-spacing: 0; width: 100%; margin: 12px 0;
  background: var(--card); border-radius: 14px; overflow: hidden;
  border: var(--hairline);
  box-shadow: var(--shadow-card);
  font-variant-numeric: tabular-nums;
  transition: background 0.3s ease;
}
th, td { border-bottom: 1px solid var(--line); padding: 10px 16px; text-align: left; font-size: 14.5px; }
th { background: var(--th-bg); color: var(--muted); font-weight: 600; font-size: 13px; letter-spacing: 0.02em; }
tr:last-child td { border-bottom: 0; }
tbody tr, tr { transition: background 0.15s; }
tr:hover td { background: var(--row-hover); }
td b { font-weight: 600; }

/* ---------- 徽标 / 公式 ---------- */
.badge {
  display: inline-block; padding: 1px 10px; border-radius: 980px; font-size: 12px;
  margin-left: 6px; vertical-align: 2px; font-weight: 500;
}
.badge.high { background: rgba(255, 69, 58, 0.16); color: #ff7a72; }
.badge.mid { background: rgba(10, 132, 255, 0.18); color: #7cb8ff; }
.badge.low { background: var(--soft); color: var(--muted); }
.badge.ok { background: rgba(48, 209, 88, 0.16); color: var(--ok); }

.alg {
  font-family: var(--mono); background: var(--chip); border-radius: 9px;
  padding: 6px 13px; display: inline-block; letter-spacing: 0.4px; font-size: 13.5px;
  color: var(--ink); font-variant-numeric: tabular-nums;
}
.alg.primary { background: var(--alg-primary-bg); box-shadow: inset 0 0 0 1px var(--alg-primary-ring); }
.step-tag {
  display: inline-block; background: var(--accent); color: #fff; border-radius: 6px;
  font-size: 11.5px; padding: 2px 8px; margin-right: 8px; font-weight: 600; letter-spacing: 0.03em;
}

/* ---------- 魔方部件 ---------- */
.cv-root { text-align: center; }
.cv-scene {
  margin: 0 auto 10px; touch-action: none; cursor: grab;
  background: var(--scene-bg); border-radius: 16px;
  transition: background 0.3s ease;
}
.cv-scene:active { cursor: grabbing; }
.cv-canvas { display: block; border-radius: 14px; }
.cv-bar { margin-top: 6px; display: flex; gap: 8px; justify-content: center; align-items: center; }
.cv-btn {
  width: 34px; height: 32px; border: 0; background: var(--soft);
  border-radius: 10px; cursor: pointer; font-size: 14px; color: var(--ink);
  transition: background 0.18s, transform 0.12s;
}
.cv-btn:hover { background: var(--soft-hover); }
.cv-btn:active { transform: scale(0.94); }
.cv-speed { width: 90px; accent-color: var(--accent); background: transparent; }
.cv-speed::-webkit-slider-runnable-track { height: 4px; border-radius: 980px; background: var(--slider-track); }
.cv-speed::-webkit-slider-thumb { margin-top: -5px; }
.cv-speed::-moz-range-track { height: 4px; border-radius: 980px; background: var(--slider-track); }
.net-root { display: flex; justify-content: center; }
.net-root svg { display: block; }

/* ---------- CMLL 图库 ---------- */
.alg-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 12px; margin: 10px 0; }
.alg-tile {
  background: var(--card); border: var(--hairline); border-radius: 14px;
  padding: 12px; text-align: center;
  display: flex; flex-direction: column; gap: 8px; align-items: center;
  box-shadow: var(--shadow-card);
}
.alg-tile b { font-size: 13.5px; letter-spacing: -0.01em; }
.alg-tile .alg { font-size: 11.5px; padding: 4px 8px; word-break: break-all; text-align: left; }
.alg-tile .src { color: var(--muted); font-size: 11.5px; }
.alg-tile .big-btn { padding: 4px 16px; font-size: 12.5px; margin: 0; }
.speed-ctl {
  display: flex; align-items: center; gap: 12px;
  background: var(--card); border: var(--hairline);
  border-radius: 12px; padding: 8px 16px; margin: 10px 0;
  font-size: 13.5px; color: var(--muted);
  box-shadow: var(--shadow-card);
  width: fit-content;
}
.speed-ctl input { width: 160px; accent-color: var(--accent); background: transparent; }
.speed-ctl input::-webkit-slider-runnable-track { height: 4px; border-radius: 980px; background: var(--slider-track); }
.speed-ctl input::-webkit-slider-thumb { margin-top: -5px; }
.speed-ctl input::-moz-range-track { height: 4px; border-radius: 980px; background: var(--slider-track); }
.speed-ctl b { color: var(--ink); font-variant-numeric: tabular-nums; min-width: 42px; }
.cmll-famnav { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0; }
.cmll-famnav button {
  border: 0; background: var(--soft); color: var(--ink);
  padding: 7px 17px; border-radius: 980px; cursor: pointer; font-size: 14px; font-family: inherit;
  transition: background 0.18s, color 0.18s;
}
.cmll-famnav button:hover { background: var(--soft-hover); }
.cmll-famnav button.active { background: var(--pill-active-bg); color: var(--pill-active-ink); box-shadow: var(--pill-active-shadow); }
.cmll-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(310px, 1fr)); gap: 16px; }
.cmll-card {
  background: var(--card); border-radius: 16px; padding: 16px 18px;
  border: var(--hairline);
  box-shadow: var(--shadow-card);
  transition: background 0.3s ease, border-color 0.3s ease;
}
.cmll-card h4 { margin: 0 0 4px; font-size: 15.5px; letter-spacing: -0.01em; }
.cmll-card .hints { color: var(--muted); font-size: 13px; margin: 4px 0 8px; line-height: 1.6; }
.cmll-card .algs { display: flex; flex-direction: column; gap: 6px; margin: 8px 0; align-items: stretch; }
.cmll-card .algs .alg { font-size: 13px; padding: 5px 11px; }
.alt-toggle {
  border: 0; background: transparent; color: var(--muted); font-family: inherit;
  font-size: 12.5px; text-align: left; padding: 2px 2px; cursor: pointer;
  transition: color 0.18s;
}
.alt-toggle:hover { color: var(--accent-hover); }
.alt-algs { display: none; flex-direction: column; gap: 6px; }
.alt-algs.open { display: flex; }
.mini-wrap { display: flex; gap: 12px; align-items: flex-start; justify-content: center; flex-wrap: wrap; }

/* ---------- 训练器 ---------- */
.trainer-box { text-align: center; }
.trainer-stats { display: flex; gap: 20px; justify-content: center; color: var(--muted); font-size: 14px; margin: 6px 0; }
.big-btn {
  background: var(--accent); color: #fff; border: 0; border-radius: 980px;
  padding: 10px 26px; font-size: 15px; font-family: inherit; font-weight: 500;
  cursor: pointer; margin: 6px 4px;
  transition: background 0.18s, transform 0.12s, box-shadow 0.18s;
  box-shadow: var(--btn-shadow);
}
.big-btn:hover { background: var(--accent-hover); }
.big-btn:active { transform: scale(0.97); }
.big-btn.ghost { background: var(--soft); color: var(--ink); box-shadow: none; }
.big-btn.ghost:hover { background: var(--soft-hover); }
.answer-panel { min-height: 30px; margin: 10px 0; }

/* ---------- 弹窗 ---------- */
.modal-mask {
  position: fixed; inset: 0; background: var(--mask-bg);
  -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px);
  display: none; align-items: center; justify-content: center; z-index: 120;
}
.modal-mask.open { display: flex; }
.modal {
  background: var(--card); border-radius: 22px; padding: 26px 30px; width: min(440px, 92vw);
  border: var(--hairline);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.5);
}
.modal h3 { margin: 0 0 8px; font-size: 19px; }
.modal .row { display: flex; align-items: center; gap: 10px; margin: 12px 0; font-size: 14.5px; }
.modal select {
  padding: 7px 12px; border-radius: 10px; border: 1px solid var(--line-strong);
  font-size: 15px; font-family: inherit; background: var(--select-bg); color: var(--ink); flex: 1;
}
.modal .hint { color: var(--muted); font-size: 13.5px; line-height: 1.6; }
.scheme-dot { display: inline-block; width: 15px; height: 15px; border-radius: 4px; vertical-align: -3px; margin-right: 4px; border: 1px solid var(--dot-border); }

/* ---------- 首次引导 ---------- */
.ob-mask {
  position: fixed; inset: 0; z-index: 110;
  background: var(--ob-mask-bg);
  -webkit-backdrop-filter: saturate(160%) blur(24px); backdrop-filter: saturate(160%) blur(24px);
  display: flex; align-items: center; justify-content: center; padding: 20px;
  opacity: 0; transition: opacity 0.35s ease;
}
.ob-mask.show { opacity: 1; }
.ob-card {
  background: var(--card); border-radius: 26px; width: min(600px, 96vw);
  border: var(--hairline);
  padding: 38px 40px 30px; box-shadow: 0 30px 90px rgba(0, 0, 0, 0.45);
  transform: translateY(10px); transition: transform 0.35s ease;
}
.ob-mask.show .ob-card { transform: translateY(0); }
.ob-logo { display: flex; gap: 7px; margin-bottom: 16px; }
.ob-logo i { width: 20px; height: 20px; border-radius: 6px; display: block; }
.ob-card h2 { margin: 0 0 6px; font-size: 24px; }
.ob-sub { color: var(--muted); margin: 0 0 20px; font-size: 14.5px; line-height: 1.65; }
.ob-opts { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
@media (max-width: 700px) { .ob-opts { grid-template-columns: 1fr; } }
.ob-opt {
  text-align: left; border: 1.5px solid transparent; background: var(--chip);
  border-radius: 16px; padding: 16px 15px; cursor: pointer; font-family: inherit; color: var(--ink);
  display: flex; flex-direction: column; gap: 6px;
  transition: border-color 0.18s, background 0.18s, transform 0.18s, box-shadow 0.18s;
}
.ob-opt:hover { transform: translateY(-2px); background: var(--opt-hover-bg); border-color: var(--accent); box-shadow: 0 10px 28px rgba(10, 132, 255, 0.2); }
.ob-opt .ob-tag {
  align-self: flex-start; font-size: 11px; font-weight: 600; color: var(--tag-ink);
  background: var(--accent-soft); border-radius: 980px; padding: 1px 9px;
}
.ob-opt b { font-size: 15px; letter-spacing: -0.01em; }
.ob-opt span:last-child { font-size: 12.5px; color: var(--muted); line-height: 1.55; }
.ob-foot { color: var(--muted); font-size: 12.5px; margin: 18px 0 0; text-align: center; }

/* ---------- 提示框 / 其他 ---------- */
.note {
  background: var(--accent-soft); color: var(--ink);
  padding: 12px 18px; border-radius: 14px; margin: 14px 0; font-size: 14.5px; line-height: 1.7;
}
.note.warn { background: rgba(255, 159, 10, 0.14); }
.note.ok { background: rgba(48, 209, 88, 0.13); }
.footer { color: var(--muted); font-size: 13px; text-align: center; padding: 44px 20px 14px; }
.footer a { color: var(--muted); text-decoration: underline; text-underline-offset: 3px; text-decoration-color: var(--footer-underline); }
.footer a:hover { color: var(--accent-hover); }
.checklist { padding-left: 0; list-style: none; }
.checklist li { padding: 3px 0; }
.checklist li::before { content: "☐"; color: var(--accent); font-weight: 600; margin-right: 9px; }
.toc {
  background: var(--card); border-radius: 14px; padding: 10px 18px; font-size: 14px;
  border: var(--hairline);
  box-shadow: var(--shadow-card); display: inline-block;
}
.toc a { margin-right: 4px; }

/* 视频嵌入 */
.video-wrap { position: relative; padding-top: 56.25%; border-radius: 14px; overflow: hidden; background: #000; }
.video-wrap iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }

/* ---------- 浅色主题微调 ---------- */
:root[data-theme="light"] .badge.high { background: rgba(255, 59, 48, 0.10); color: #d70015; }
:root[data-theme="light"] .badge.mid { background: rgba(0, 113, 227, 0.10); color: #0062cc; }
:root[data-theme="light"] .badge.ok { background: rgba(52, 199, 89, 0.14); color: #1d8a41; }
:root[data-theme="light"] .note.warn { background: rgba(255, 159, 10, 0.13); }
:root[data-theme="light"] .note.ok { background: rgba(52, 199, 89, 0.12); }
:root[data-theme="light"] .ob-opt:hover { box-shadow: 0 10px 28px rgba(0, 113, 227, 0.14); }
:root[data-theme="light"] .ob-tag { color: var(--accent); }

/* ---------- 桌面微美化 ---------- */
body { -webkit-tap-highlight-color: transparent; }
@media (hover: hover) {
  .cmll-card { transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease; }
  .cmll-card:hover { transform: translateY(-2px); border-color: rgba(255, 255, 255, 0.14); }
  :root[data-theme="light"] .cmll-card:hover { border-color: rgba(0, 0, 0, 0.10); }
}

/* ---------- 移动端适配 (≤700px) ---------- */
@media (max-width: 700px) {
  /* 头部：第一行 logo + 模式 + 主题 + 配色；第二行页面导航横向滑动 */
  .site-header { padding: 8px 12px; gap: 6px; }
  .site-header .logo { font-size: 16px; }
  .site-header .spacer { order: 4; }
  .scheme-btn { padding: 6px 9px; font-size: 12.5px; }
  .mode-seg { order: 5; }
  .mode-seg button { padding: 4px 9px; font-size: 12.5px; }
  .site-header nav {
    order: 10; flex-basis: 100%;
    flex-wrap: nowrap; overflow-x: auto;
    scrollbar-width: none; -webkit-overflow-scrolling: touch;
    margin: 0 -4px; padding: 2px 4px;
  }
  .site-header nav::-webkit-scrollbar { display: none; }
  .site-header nav a { flex: 0 0 auto; padding: 9px 13px; }

  main { padding: 24px 16px 60px; }
  h1 { font-size: 25px; }
  h2 { font-size: 19px; margin: 30px 0 10px; }
  .lead { font-size: 15px; }

  .card { padding: 16px; border-radius: 16px; }
  .grid2, .grid3, .grid4 { gap: 10px; }

  /* 宽表格横向滑动 */
  table { display: block; overflow-x: auto; -webkit-overflow-scrolling: touch; }
  th, td { padding: 8px 12px; font-size: 13.5px; white-space: nowrap; }
  table th, table td:first-child { white-space: normal; min-width: 3.5em; }

  .cmll-grid { grid-template-columns: 1fr; gap: 10px; }
  .cmll-card { padding: 14px; }
  .mini-wrap { gap: 8px; }
  .toc { display: block; line-height: 2; }

  .big-btn { min-height: 44px; }
  .modal { padding: 22px 20px; }
  .modal select { font-size: 16px; } /* 防 iOS 聚焦缩放 */
  .ob-card { padding: 26px 20px 22px; border-radius: 20px; }
  .track-notice { font-size: 13px; padding: 9px 13px; }
  .footer { padding: 30px 16px 12px; }
}

/* 极窄屏 (≤360px) */
@media (max-width: 360px) {
  .mode-seg button { padding: 4px 8px; }
  .scheme-btn { padding: 6px 8px; }
  h1 { font-size: 23px; }
}