/* ===== OB体育官网 / 共享样式表 site.css ===== */

/* 1. Reset */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body, h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }
ul[class], ol[class] { list-style: none; padding: 0; }
img, svg, video, canvas { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
a { color: inherit; }

/* 2. 变量 */
:root {
  --ob-ink: #0D1210;
  --ob-panel: #12352C;
  --ob-panel-2: #1D5648;
  --ob-yellow: #FFC73A;
  --ob-red: #E0473B;
  --ob-cream: #F3EDE0;
  --ob-bone: #E9E6DE;
  --ob-slate: #8A98A6;
  --ob-brown: #2B211A;
  --ob-highlight: #FFF0C2;

  --ob-rail: 220px;
  --ob-maxw: 1480px;
  --ob-gutter: clamp(16px, 3vw, 40px);
  --ob-radius-lg: 28px;
  --ob-radius-md: 18px;
  --ob-radius-sm: 12px;
  --ob-line: rgba(138, 152, 166, .22);
  --ob-line-soft: rgba(138, 152, 166, .14);

  --ob-font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --ob-font-mono: "IBM Plex Mono", "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  --ob-ease: cubic-bezier(.2, .7, .3, 1);
  --ob-dur: 200ms;
}

/* 3. 基础排版 */
body {
  background: var(--ob-ink);
  color: var(--ob-bone);
  font-family: var(--ob-font-sans);
  font-size: 16px;
  line-height: 1.8;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -.02em; }
p { line-height: 1.85; }
:focus-visible { outline: 2px solid var(--ob-yellow); outline-offset: 3px; border-radius: 6px; }
#main-content { scroll-margin-top: 24px; }
.ob-mono { font-family: var(--ob-font-mono); font-variant-numeric: tabular-nums; }

/* 4. Skip link */
.ob-skip {
  position: absolute;
  left: 12px;
  top: -60px;
  z-index: 120;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--ob-yellow);
  color: var(--ob-ink);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transition: top var(--ob-dur) var(--ob-ease);
}
.ob-skip:focus { top: 12px; }

/* 5. 头部 */
.ob-header {
  display: grid;
  grid-template-columns: var(--ob-rail) minmax(0, 1fr);
  width: 100%;
  background: var(--ob-ink);
  border-bottom: 1px solid var(--ob-line);
}
.ob-header__rail {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 18px;
  padding: 22px 20px;
  background: linear-gradient(180deg, var(--ob-panel) 0%, rgba(13, 18, 16, .9) 88%);
  border-right: 1px solid var(--ob-line-soft);
}
.ob-header__main {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

/* 品牌 */
.ob-brand {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  text-decoration: none;
  color: inherit;
}
.ob-brand--footer { gap: 10px 12px; }
.ob-brand__mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: var(--ob-radius-sm);
  background: var(--ob-yellow);
  color: var(--ob-ink);
  font-family: var(--ob-font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -.02em;
}
.ob-brand__name {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -.01em;
  line-height: 1.2;
}
.ob-brand__sub {
  flex-basis: 100%;
  font-family: var(--ob-font-mono);
  font-size: 10px;
  letter-spacing: .32em;
  text-transform: uppercase;
  color: var(--ob-slate);
}

/* 纵向旋转小注 */
.ob-rail-note {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .34em;
  color: var(--ob-slate);
  border-left: 1px solid rgba(138, 152, 166, .35);
  padding-left: 9px;
  margin-top: auto;
}

/* 双层导航：上层 */
.ob-utility {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 18px;
  padding: 12px var(--ob-gutter);
  background: rgba(18, 53, 44, .42);
  border-bottom: 1px solid var(--ob-line-soft);
  font-size: 12px;
}
.ob-utility__line {
  margin: 0;
  font-family: var(--ob-font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--ob-yellow);
}
.ob-utility__meta {
  margin-left: auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  color: var(--ob-slate);
}
.ob-utility__link {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  border-radius: 999px;
  border: 1px solid rgba(255, 199, 58, .45);
  color: var(--ob-bone);
  font-family: var(--ob-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  text-decoration: none;
  transition: background var(--ob-dur) var(--ob-ease), color var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease);
}
.ob-utility__link:hover { background: var(--ob-yellow); color: var(--ob-ink); border-color: var(--ob-yellow); }

.ob-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border-radius: 999px;
  border: 1px solid rgba(138, 152, 166, .4);
  color: var(--ob-slate);
  font-family: var(--ob-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
}
.ob-pill--ghost { background: rgba(138, 152, 166, .1); }

/* 双层导航：下层栏目胶囊 */
.ob-navbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  padding: 14px var(--ob-gutter) 16px;
}
.ob-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.ob-nav__link {
  display: inline-flex;
  align-items: center;
  padding: 9px 17px;
  border-radius: 999px;
  border: 1px solid rgba(138, 152, 166, .28);
  background: rgba(29, 86, 72, .18);
  color: var(--ob-bone);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: background var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease), color var(--ob-dur) var(--ob-ease), transform var(--ob-dur) var(--ob-ease);
}
.ob-nav__link:hover {
  background: var(--ob-panel-2);
  border-color: var(--ob-panel-2);
  transform: translateY(-2px);
}
.ob-nav__link[aria-current="page"] {
  background: var(--ob-yellow);
  border-color: var(--ob-yellow);
  color: var(--ob-ink);
}

/* 移动导航按钮 */
.ob-nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  margin-left: auto;
  padding: 9px 16px;
  border-radius: 999px;
  border: 1px solid rgba(255, 199, 58, .5);
  background: rgba(255, 199, 58, .1);
  color: var(--ob-yellow);
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: background var(--ob-dur) var(--ob-ease), color var(--ob-dur) var(--ob-ease);
}
.ob-nav-toggle__bars,
.ob-nav-toggle__bars::before,
.ob-nav-toggle__bars::after {
  display: block;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
}
.ob-nav-toggle__bars { position: relative; }
.ob-nav-toggle__bars::before,
.ob-nav-toggle__bars::after { content: ""; position: absolute; left: 0; }
.ob-nav-toggle__bars::before { top: -5px; }
.ob-nav-toggle__bars::after { top: 5px; }
.ob-nav-toggle[aria-expanded="true"] { background: var(--ob-yellow); color: var(--ob-ink); }

/* 6. 通用布局 */
.ob-main { display: block; width: 100%; }
.ob-container {
  width: 100%;
  max-width: var(--ob-maxw);
  margin-inline: auto;
  padding-inline: var(--ob-gutter);
}
.ob-section { margin-block: clamp(28px, 4.5vw, 64px); }
.ob-section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: 10px 18px;
  padding-bottom: 14px;
  margin-bottom: clamp(16px, 2.4vw, 26px);
  border-bottom: 1px solid var(--ob-line);
}
.ob-section__title {
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 800;
  letter-spacing: -.02em;
}
.ob-section__note {
  margin-left: auto;
  font-family: var(--ob-font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--ob-slate);
}
.ob-rule { height: 1px; border: 0; background: var(--ob-line); margin: clamp(18px, 2.6vw, 30px) 0; }

.ob-grid { display: grid; gap: clamp(14px, 2vw, 24px); }
.ob-grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.ob-grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.ob-grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* 7. 资料卡 / 数据面板 */
.ob-card {
  background: var(--ob-panel);
  border: 1px solid var(--ob-line);
  border-radius: var(--ob-radius-md);
  padding: clamp(16px, 2.2vw, 24px);
  transition: transform var(--ob-dur) var(--ob-ease), background var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease);
}
.ob-card:hover {
  transform: translateY(-2px);
  background: #164034;
  border-color: rgba(255, 199, 58, .35);
}
.ob-card--paper {
  background: var(--ob-cream);
  color: var(--ob-brown);
  border-color: rgba(43, 33, 26, .16);
}
.ob-card--paper:hover { background: var(--ob-cream); border-color: rgba(224, 71, 59, .45); }
.ob-card__head { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-bottom: 12px; }
.ob-card__title { font-size: 18px; font-weight: 700; letter-spacing: -.01em; }
.ob-card__meta { font-family: var(--ob-font-mono); font-size: 12px; color: var(--ob-slate); }
.ob-card__body { font-size: 15px; line-height: 1.8; }

.ob-panel {
  background: var(--ob-panel);
  border: 1px solid var(--ob-line);
  border-radius: var(--ob-radius-md);
  padding: clamp(16px, 2.2vw, 24px);
}
.ob-panel__head { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-bottom: 14px; }
.ob-stat { display: grid; gap: 4px; }
.ob-stat__num {
  font-family: var(--ob-font-mono);
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--ob-yellow);
}
.ob-stat__label { font-size: 12px; letter-spacing: .04em; color: var(--ob-slate); }

/* 8. 标签 */
.ob-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border-radius: 999px;
  border: 1px solid currentColor;
  font-family: var(--ob-font-mono);
  font-size: 12px;
  font-weight: 600;
  line-height: 1.5;
  letter-spacing: .04em;
}
.ob-tag--yellow { color: var(--ob-yellow); background: rgba(255, 199, 58, .12); }
.ob-tag--red { color: var(--ob-red); background: rgba(224, 71, 59, .14); }
.ob-tag--slate { color: var(--ob-slate); background: rgba(138, 152, 166, .12); }
.ob-tag--solid-yellow { background: var(--ob-yellow); border-color: var(--ob-yellow); color: var(--ob-ink); }

/* 9. 按钮 */
.ob-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 20px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition: background var(--ob-dur) var(--ob-ease), color var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease), transform var(--ob-dur) var(--ob-ease);
}
.ob-btn--primary { background: var(--ob-yellow); color: var(--ob-ink); }
.ob-btn--primary:hover { background: #FFD666; transform: translateY(-2px); }
.ob-btn--ghost { background: transparent; color: var(--ob-bone); border-color: rgba(233, 230, 222, .35); }
.ob-btn--ghost:hover { border-color: var(--ob-yellow); color: var(--ob-yellow); transform: translateY(-2px); }
.ob-btn--dark { background: var(--ob-ink); color: var(--ob-bone); border-color: rgba(13, 18, 16, .6); }
.ob-btn--dark:hover { background: var(--ob-brown); transform: translateY(-2px); }

/* 10. 标题与正文 */
.ob-eyebrow {
  display: inline-block;
  font-family: var(--ob-font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .28em;
  text-transform: uppercase;
  color: var(--ob-yellow);
}
.ob-h1 { font-size: clamp(32px, 4.4vw, 48px); font-weight: 900; letter-spacing: -.03em; line-height: 1.08; }
.ob-h2 { font-size: clamp(24px, 2.8vw, 32px); font-weight: 800; }
.ob-h3 { font-size: 20px; font-weight: 700; }
.ob-lead { font-size: clamp(16px, 1.6vw, 18px); line-height: 1.85; color: var(--ob-slate); }
.ob-prose { font-size: 17px; line-height: 1.85; max-width: 68ch; }
.ob-prose p { margin-bottom: 1.1em; }
.ob-prose h2 { margin: 1.6em 0 .6em; font-size: 24px; }
.ob-prose h3 { margin: 1.4em 0 .5em; font-size: 19px; }
.ob-prose ul, .ob-prose ol { padding-left: 1.3em; margin-bottom: 1.1em; }
.ob-prose li { margin-bottom: .4em; }
.ob-prose--paper {
  background: var(--ob-cream);
  color: var(--ob-brown);
  border-radius: var(--ob-radius-lg);
  padding: clamp(20px, 3vw, 40px);
}
.ob-prose--paper .ob-eyebrow { color: #8C5A12; }
.ob-sidenote {
  font-size: 12px;
  line-height: 1.75;
  color: var(--ob-slate);
  border-left: 2px solid var(--ob-panel-2);
  padding-left: 12px;
}
.ob-vlabel {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .36em;
  color: var(--ob-slate);
}

/* 11. 面包屑 */
.ob-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--ob-font-mono);
  font-size: 12px;
  color: var(--ob-slate);
}
.ob-crumbs a { color: var(--ob-slate); text-decoration: none; border-bottom: 1px solid transparent; }
.ob-crumbs a:hover { color: var(--ob-yellow); border-bottom-color: currentColor; }
.ob-crumbs__sep { color: rgba(138, 152, 166, .5); }
.ob-crumbs [aria-current="page"] { color: var(--ob-bone); }

/* 12. 图片容器（页面阶段放图） */
.ob-figure {
  margin: 0;
  border-radius: var(--ob-radius-lg);
  overflow: hidden;
  background: linear-gradient(140deg, var(--ob-panel) 0%, var(--ob-ink) 78%);
  border: 1px solid var(--ob-line);
}
.ob-figure__media { position: relative; aspect-ratio: 16 / 9; background-color: var(--ob-panel); }
.ob-figure__media img { width: 100%; height: 100%; object-fit: cover; }
.ob-figure__media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(138, 152, 166, .16) 1px, transparent 1px),
    linear-gradient(90deg, rgba(138, 152, 166, .16) 1px, transparent 1px);
  background-size: 44px 44px;
  opacity: .45;
}
.ob-figure--wide .ob-figure__media { aspect-ratio: 21 / 9; }
.ob-figure--square .ob-figure__media { aspect-ratio: 1 / 1; }
.ob-figure--tall .ob-figure__media { aspect-ratio: 3 / 4; }
.ob-figure__cap {
  padding: 12px 16px;
  border-top: 1px solid var(--ob-line);
  font-family: var(--ob-font-mono);
  font-size: 12px;
  color: var(--ob-slate);
}

/* 13. 筛选条 */
.ob-filter { display: flex; flex-wrap: wrap; gap: 8px; }
.ob-filter__btn {
  padding: 7px 15px;
  border-radius: 999px;
  border: 1px solid rgba(138, 152, 166, .3);
  background: transparent;
  color: var(--ob-bone);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--ob-dur) var(--ob-ease), color var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease);
}
.ob-filter__btn:hover { border-color: var(--ob-yellow); color: var(--ob-yellow); }
.ob-filter__btn[aria-pressed="true"] { background: var(--ob-yellow); border-color: var(--ob-yellow); color: var(--ob-ink); }
[data-filter-item][hidden] { display: none; }

/* 14. 页脚 */
.ob-footer {
  margin-top: clamp(40px, 6vw, 80px);
  background:
    radial-gradient(120% 100% at 8% 0%, rgba(29, 86, 72, .55), transparent 62%),
    var(--ob-ink);
  border-top: 1px solid var(--ob-line);
  color: var(--ob-bone);
}
.ob-footer__inner {
  width: 100%;
  max-width: var(--ob-maxw);
  margin-inline: auto;
  padding: clamp(28px, 4vw, 52px) var(--ob-gutter) clamp(18px, 2.4vw, 26px);
}
.ob-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.9fr);
  gap: clamp(24px, 4vw, 56px);
  padding-bottom: clamp(22px, 3vw, 34px);
  border-bottom: 1px solid var(--ob-line);
}
.ob-footer__brand { min-width: 0; }
.ob-footer__claim {
  margin-top: 16px;
  max-width: 42ch;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ob-slate);
}
.ob-footer__contact {
  margin-top: 16px;
  display: grid;
  gap: 6px;
  font-size: 13px;
  color: var(--ob-slate);
}
.ob-footer__contact-item { font-family: var(--ob-font-mono); color: var(--ob-bone); }
.ob-footer__cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 2.4vw, 32px);
}
.ob-footer__col { min-width: 0; }
.ob-footer__title {
  margin-bottom: 12px;
  font-family: var(--ob-font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ob-yellow);
}
.ob-footer__list { display: grid; gap: 9px; }
.ob-footer__list a {
  display: inline-block;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ob-slate);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease);
}
.ob-footer__list a:hover { color: var(--ob-bone); border-bottom-color: var(--ob-yellow); }
.ob-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: clamp(16px, 2.4vw, 24px);
  font-size: 12px;
  color: var(--ob-slate);
}
.ob-footer__legal { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.ob-footer__sep { color: rgba(138, 152, 166, .5); }
.ob-footer__links { display: flex; flex-wrap: wrap; gap: 14px; }
.ob-footer__links a {
  color: var(--ob-slate);
  text-decoration: none;
  border-bottom: 1px solid rgba(138, 152, 166, .4);
  transition: color var(--ob-dur) var(--ob-ease), border-color var(--ob-dur) var(--ob-ease);
}
.ob-footer__links a:hover { color: var(--ob-yellow); border-bottom-color: var(--ob-yellow); }

/* 15. 脚本注入：滚动进度与返回顶部 */
.ob-progress {
  position: fixed;
  inset: 0 0 auto 0;
  height: 3px;
  background: rgba(138, 152, 166, .18);
  pointer-events: none;
  z-index: 90;
}
.ob-progress__bar {
  display: block;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--ob-yellow), var(--ob-red));
}
.ob-totop {
  position: fixed;
  right: clamp(14px, 2.4vw, 32px);
  bottom: clamp(14px, 2.4vw, 32px);
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 1px solid rgba(255, 199, 58, .5);
  background: var(--ob-panel);
  color: var(--ob-yellow);
  font-size: 18px;
  line-height: 1;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--ob-dur) var(--ob-ease), transform var(--ob-dur) var(--ob-ease), visibility var(--ob-dur), background var(--ob-dur) var(--ob-ease);
  z-index: 80;
}
.ob-totop.is-visible { opacity: 1; visibility: visible; transform: none; }
.ob-totop:hover { background: var(--ob-yellow); color: var(--ob-ink); }

/* 16. 显现（需 JS，html.js 生效） */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 260ms var(--ob-ease), transform 260ms var(--ob-ease);
}
html.js [data-reveal].is-in { opacity: 1; transform: none; }

/* 17. 响应式：平板与移动 */
@media (max-width: 1080px) {
  .ob-grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .ob-grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .ob-footer__top { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 900px) {
  .ob-header { grid-template-columns: minmax(0, 1fr); }
  .ob-header__rail {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    padding: 14px var(--ob-gutter);
    border-right: 0;
    border-bottom: 1px solid var(--ob-line-soft);
    background: linear-gradient(90deg, var(--ob-panel) 0%, rgba(13, 18, 16, .9) 90%);
  }
  .ob-rail-note {
    writing-mode: horizontal-tb;
    border-left: 0;
    padding-left: 0;
    margin-top: 0;
    letter-spacing: .18em;
    max-width: 44vw;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
  .ob-brand__sub { display: none; }
  .ob-utility { padding: 10px var(--ob-gutter); }
  .ob-utility__meta { margin-left: 0; }
  .ob-navbar { padding: 12px var(--ob-gutter) 16px; }
  .ob-nav-toggle { display: inline-flex; }
  .ob-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    gap: 6px;
    padding-top: 10px;
  }
  .ob-nav[data-open] { display: flex; }
  .ob-nav__link { justify-content: flex-start; padding: 12px 16px; border-radius: 14px; }
}

@media (max-width: 640px) {
  .ob-grid--2, .ob-grid--3, .ob-grid--4 { grid-template-columns: minmax(0, 1fr); }
  .ob-footer__cols { grid-template-columns: minmax(0, 1fr); }
  .ob-section__note { margin-left: 0; width: 100%; }
  .ob-footer__bottom { flex-direction: column; align-items: flex-start; }
}

/* 18. 降低动效偏好 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
  html.js [data-reveal] { opacity: 1 !important; transform: none !important; }
  .ob-totop { transition: none; }
}