/* ==========================================================================
   米乐娱乐 · 共享外壳样式  /assets/site.css
   高原观赛台：暗夜蓝底 + 雪山白字 + 经幡五色克制点缀
   ========================================================================== */

/* 1. Reset ---------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 96px; }
body, h1, h2, h3, h4, h5, p, ul, ol, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; }
img, picture, svg, video { max-width: 100%; display: block; }
input, button, textarea, select { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
:focus-visible { outline: 2px solid var(--yellow); outline-offset: 3px; }
::selection { background: var(--yellow); color: var(--ink); }

/* 2. Tokens --------------------------------------------------------------- */
:root {
  --night: #0B1B33;
  --night-2: #12294A;
  --ink: #050B16;
  --snow: #F5F7FA;
  --dust: #9AA7BC;
  --blue: #2E7DD1;
  --red: #D93A3A;
  --green: #2FA36B;
  --yellow: #F2C14E;
  --line: #1E3A63;

  --shell: 1240px;
  --gutter: clamp(16px, 4vw, 40px);
  --stack: clamp(20px, 3vw, 36px);
  --block: clamp(44px, 7vw, 96px);

  --font-head: "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-num: "JetBrains Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --ease: cubic-bezier(.22, .61, .36, 1);
  --dur: .2s;
  --edge: 2px solid var(--line);
  --hard: 4px 4px 0 0 #050B16;
  --hard-lg: 7px 7px 0 0 #050B16;
}

/* 3. 基底与中文排版 --------------------------------------------------------- */
body {
  min-height: 100vh;
  background-color: var(--night);
  background-image:
    radial-gradient(1100px 620px at 84% -8%, rgba(46, 125, 209, .20), transparent 62%),
    radial-gradient(820px 520px at 6% 10%, rgba(217, 58, 58, .10), transparent 60%),
    radial-gradient(900px 700px at 50% 108%, rgba(47, 163, 107, .08), transparent 65%),
    linear-gradient(180deg, #0B1B33 0%, #0B1B33 58%, #071427 100%);
  background-attachment: fixed;
  color: var(--snow);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.8;
  letter-spacing: .005em;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* 颗粒噪点肌理：避免大面积纯色平板 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background-image: radial-gradient(rgba(245, 247, 250, .055) 1px, transparent 1.2px);
  background-size: 4px 4px;
  opacity: .7;
}

#main-content { display: block; }

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -.02em;
  color: var(--snow);
}
h1 { font-size: clamp(40px, 6vw, 72px); line-height: 1.02; }
h2 { font-size: clamp(22px, 3vw, 28px); font-weight: 700; }
h3 { font-size: 19px; font-weight: 700; line-height: 1.4; }
p { overflow-wrap: break-word; }

.mono, code, kbd, samp { font-family: var(--font-num); }
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.eyebrow {
  display: inline-block;
  font-family: var(--font-num);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--dust);
}
.divider { height: 2px; border: 0; background: var(--line); margin-block: var(--stack); }
.rule {
  height: 2px; border: 0; margin: clamp(18px, 3vw, 32px) 0;
  background: linear-gradient(90deg, var(--line) 0%, rgba(30, 58, 99, .1) 70%, transparent 100%);
}
.vertical-note {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--dust);
  writing-mode: vertical-rl;
}

/* 4. 布局 ----------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.container--narrow { max-width: 820px; }

.grid-12 { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: clamp(14px, 2vw, 28px); }
.grid-12 > * { grid-column: 1 / -1; }
@media (min-width: 900px) {
  .grid-12 > .span-2 { grid-column: span 2; }
  .grid-12 > .span-3 { grid-column: span 3; }
  .grid-12 > .span-4 { grid-column: span 4; }
  .grid-12 > .span-5 { grid-column: span 5; }
  .grid-12 > .span-6 { grid-column: span 6; }
  .grid-12 > .span-7 { grid-column: span 7; }
  .grid-12 > .span-8 { grid-column: span 8; }
  .grid-12 > .span-9 { grid-column: span 9; }
  .grid-12 > .span-10 { grid-column: span 10; }
  .grid-12 > .span-12 { grid-column: span 12; }
}

.auto-grid { display: grid; gap: clamp(14px, 2vw, 24px); grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }

/* 非对称编辑部版式：窄注释栏 + 宽内容区 */
.rail-layout { display: grid; gap: var(--stack); grid-template-columns: 1fr; }
.rail-layout__rail { align-self: start; }
.rail-layout__body { min-width: 0; }
@media (min-width: 900px) {
  .rail-layout { grid-template-columns: minmax(0, 22%) minmax(0, 1fr); }
  .rail-layout--right { grid-template-columns: minmax(0, 1fr) minmax(0, 22%); }
  .rail-layout__rail { position: sticky; top: 112px; }
}

/* 5. 章节节奏 -------------------------------------------------------------- */
.section { padding-block: var(--block); }
.section--tight { padding-block: clamp(28px, 4vw, 52px); }
.section--deep { background: var(--night-2); border-block: var(--edge); }
.section--ink { background: var(--ink); border-top: var(--edge); }
.section--edge { border-top: var(--edge); }
.section__title { margin-bottom: 12px; }
.section__lead { max-width: 62ch; color: var(--dust); font-size: 16.5px; }

/* 6. 正文 ----------------------------------------------------------------- */
.prose { max-width: 70ch; font-size: 17px; }
.prose > * + * { margin-top: 1.05em; }
.prose h2 { margin-top: 1.9em; }
.prose h3 { margin-top: 1.6em; }
.prose ul { list-style: square; padding-left: 1.15em; }
.prose ol { list-style: decimal; padding-left: 1.3em; }
.prose li + li { margin-top: .4em; }
.prose a { color: var(--blue); text-underline-offset: 3px; text-decoration: underline; }
.prose strong { color: var(--snow); font-weight: 700; }
.prose blockquote {
  border-left: 2px solid var(--yellow);
  padding-left: 16px;
  color: var(--dust);
}
.lede { font-size: clamp(18px, 2.1vw, 21px); line-height: 1.7; max-width: 60ch; }

/* 7. 按钮 ----------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 2px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--snow);
  font-family: var(--font-head);
  font-size: 14.5px;
  font-weight: 700;
  letter-spacing: .04em;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color .16s var(--ease), border-color .16s var(--ease), color .16s var(--ease), transform .16s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn--solid { background: var(--red); border-color: var(--red); color: var(--snow); }
.btn--solid:hover { background: #b92f2f; border-color: #b92f2f; }
.btn--ghost { background: rgba(18, 41, 74, .78); }
.btn--ghost:hover { border-color: var(--blue); background: rgba(46, 125, 209, .22); }
.btn--line { background: transparent; }
.btn--line:hover { border-color: var(--blue); color: var(--blue); }

/* 8. 卡片与数据组件 -------------------------------------------------------- */
.card {
  position: relative;
  display: block;
  padding: clamp(18px, 2.4vw, 26px);
  background: var(--night-2);
  border: var(--edge);
  box-shadow: var(--hard);
  color: inherit;
  text-decoration: none;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.card:hover { transform: translateY(-2px); border-color: var(--blue); }
.card--flush { padding: 0; overflow: hidden; }
.card__kicker {
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--dust);
}
.card__title {
  margin-top: 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(20px, 2.4vw, 26px);
  line-height: 1.25;
  letter-spacing: -.01em;
}
.card__text { margin-top: 10px; color: var(--dust); font-size: 15.5px; }
.card__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--dust);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: 1px solid var(--line);
  background: rgba(5, 11, 22, .5);
  color: var(--dust);
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
}
.tag--blue { color: var(--blue); border-color: rgba(46, 125, 209, .55); }
.tag--green { color: var(--green); border-color: rgba(47, 163, 107, .55); }
.tag--yellow { color: var(--yellow); border-color: rgba(242, 193, 78, .55); }
.tag--red { color: var(--red); border-color: rgba(217, 58, 58, .55); }

.stat {
  padding: 16px 18px;
  background: var(--night-2);
  border: var(--edge);
  box-shadow: var(--hard);
}
.stat__value {
  font-family: var(--font-num);
  font-size: clamp(26px, 3.6vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--snow);
}
.stat__label {
  margin-top: 8px;
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .12em;
  color: var(--dust);
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--dust);
}
.legend__item { display: inline-flex; align-items: center; gap: 7px; }
.legend__dot {
  width: 10px; height: 10px;
  border: 1px solid var(--line);
  background: var(--dust);
}
.legend__dot--blue { background: var(--blue); }
.legend__dot--red { background: var(--red); }
.legend__dot--green { background: var(--green); }
.legend__dot--yellow { background: var(--yellow); }

/* 9. 图片容器基类（页面阶段放置图片占位）------------------------------------- */
.media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: var(--edge);
  box-shadow: var(--hard);
  background-color: var(--night-2);
  background-image:
    linear-gradient(180deg, rgba(11, 27, 51, .10) 0%, rgba(5, 11, 22, .82) 100%),
    linear-gradient(135deg, #16305A 0%, #0B1B33 55%, #050B16 100%);
}
.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .5;
  background-image:
    repeating-linear-gradient(0deg, rgba(154, 167, 188, .16) 0 1px, transparent 1px 44px),
    repeating-linear-gradient(90deg, rgba(154, 167, 188, .16) 0 1px, transparent 1px 44px);
}
.media > img,
.media > picture > img {
  position: absolute;
  inset: 0;
  z-index: 1;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 2;
  padding: 9px 14px;
  background: rgba(5, 11, 22, .86);
  border-top: 2px solid var(--line);
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--dust);
}
.media--wide { aspect-ratio: 21 / 9; }
.media--band { aspect-ratio: 5 / 2; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }

/* 10. 面包屑 --------------------------------------------------------------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--dust);
}
.breadcrumb__item { color: var(--dust); text-decoration: none; }
a.breadcrumb__item:hover { color: var(--snow); }
.breadcrumb__item[aria-current="page"] { color: var(--snow); }
.breadcrumb__sep { color: rgba(154, 167, 188, .45); }

/* 11. 跳转链接与阅读进度 ---------------------------------------------------- */
.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 200;
  transform: translateY(-180%);
  padding: 10px 16px;
  background: var(--yellow);
  border: 2px solid var(--ink);
  color: var(--ink);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 14px;
  text-decoration: none;
  transition: transform .18s var(--ease);
}
.skip-link:focus { transform: translateY(0); }

.scroll-progress {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 2px;
  z-index: 120;
  background: rgba(30, 58, 99, .55);
  pointer-events: none;
}
.scroll-progress > span {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--yellow);
  transform: scaleX(0);
  transform-origin: left center;
}

/* 12. 页头：悬浮胶囊浮岛 ---------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  padding: 10px var(--gutter) 14px;
  border-bottom: 1px solid transparent;
  background: linear-gradient(180deg, rgba(5, 11, 22, .90) 0%, rgba(5, 11, 22, .62) 62%, rgba(5, 11, 22, 0) 100%);
  transition: background-color .28s var(--ease), padding .28s var(--ease), border-color .28s var(--ease);
}
.site-header[data-stuck] {
  padding-block: 8px;
  border-bottom-color: var(--line);
  background: rgba(5, 11, 22, .95);
  box-shadow: 0 16px 34px -28px #000;
}
.site-header__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  max-width: var(--shell);
  margin-inline: auto;
}

.brand {
  flex: 0 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1px;
  padding: 8px 14px;
  background: rgba(18, 41, 74, .92);
  border: var(--edge);
  box-shadow: var(--hard);
  text-decoration: none;
  transition: border-color .16s var(--ease), background-color .16s var(--ease);
}
.brand:hover { border-color: var(--blue); }
.brand__mark {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 17px;
  line-height: 1.25;
  letter-spacing: .08em;
  color: var(--snow);
}
.brand__tagline {
  font-family: var(--font-num);
  font-size: 10.5px;
  line-height: 1.3;
  letter-spacing: .1em;
  color: var(--dust);
}

.nav {
  order: 3;
  flex: 1 1 100%;
  display: none;
  padding: 10px;
  background: rgba(18, 41, 74, .97);
  border: var(--edge);
  box-shadow: var(--hard);
}
.nav[data-open] { display: block; }
.nav__legend {
  margin: 0 0 8px 4px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--dust);
}
.nav__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
  list-style: none;
}
.nav__link {
  display: block;
  padding: 11px 14px;
  border-left: 2px solid transparent;
  color: var(--snow);
  font-size: 15.5px;
  text-decoration: none;
  transition: background-color .16s var(--ease), border-color .16s var(--ease);
}
.nav__link:hover { background: rgba(46, 125, 209, .18); border-left-color: var(--blue); }
.nav__link[aria-current="page"] {
  background: var(--blue);
  border-left-color: var(--snow);
  color: #fff;
}

.header-actions {
  order: 4;
  flex: 1 1 100%;
  display: none;
  flex-wrap: wrap;
  gap: 8px;
}
.nav[data-open] ~ .header-actions { display: flex; }
.header-actions .btn { flex: 1 1 150px; }

.nav-toggle {
  order: 2;
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 10px 14px;
  background: rgba(18, 41, 74, .92);
  border: var(--edge);
  box-shadow: var(--hard);
  color: var(--snow);
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .16em;
  transition: border-color .16s var(--ease);
}
.nav-toggle:hover { border-color: var(--blue); }
.nav-toggle__bars { display: flex; flex-direction: column; gap: 4px; width: 18px; }
.nav-toggle__bars i {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--yellow);
  transition: transform .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:first-child { transform: translateY(3px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:last-child { transform: translateY(-3px) rotate(-45deg); }

@media (min-width: 1024px) {
  .site-header { padding-block: 16px; }
  .site-header[data-stuck] { padding-block: 8px; }
  .site-header[data-stuck] .brand__tagline { display: none; }
  .site-header__inner { flex-wrap: nowrap; gap: 16px; }
  .site-header[data-stuck] .nav__link { padding-block: 7px; }

  .brand { padding: 9px 16px; }
  .nav {
    order: 0;
    flex: 1 1 auto;
    display: flex;
    justify-content: center;
    padding: 5px;
    border-radius: 999px;
    background: rgba(18, 41, 74, .72);
    box-shadow: none;
  }
  .nav__legend { display: none; }
  .nav__list { flex-direction: row; justify-content: center; gap: 2px; }
  .nav__link {
    padding: 9px 15px;
    border-left: 0;
    border-radius: 999px;
    font-size: 15px;
  }
  .nav__link:hover { border-left-color: transparent; }
  .nav__link[aria-current="page"] { border-left-color: transparent; }

  .header-actions { order: 0; display: flex; flex: 0 0 auto; flex-wrap: nowrap; }
  .header-actions .btn { flex: 0 0 auto; }
  .nav-toggle { display: none; }
}

/* 13. 页脚 ----------------------------------------------------------------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 96px);
  background: var(--ink);
  border-top: var(--edge);
  color: var(--snow);
}
/* 经幡五色细带：全站唯一的五色排列 */
.site-footer::before {
  content: "";
  position: absolute;
  top: -2px; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg,
    var(--blue) 0%, var(--blue) 20%,
    var(--snow) 20%, var(--snow) 40%,
    var(--red) 40%, var(--red) 60%,
    var(--green) 60%, var(--green) 80%,
    var(--yellow) 80%, var(--yellow) 100%);
}
.site-footer__inner {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  grid-template-columns: 1fr;
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(40px, 6vw, 72px) var(--gutter) clamp(28px, 4vw, 44px);
}

.footer-brand__mark {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(30px, 4.4vw, 46px);
  line-height: 1.05;
  letter-spacing: -.01em;
  color: var(--snow);
}
.footer-brand__tagline {
  max-width: 24ch;
  margin-top: 10px;
  color: var(--dust);
  font-size: 14.5px;
}
.footer-brand__coord {
  margin-top: 12px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--blue);
}
.footer-brand .legend { margin-top: 20px; }

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-top: 22px;
  padding: 9px 16px;
  background: transparent;
  border: 2px solid var(--line);
  border-radius: 999px;
  color: var(--snow);
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .12em;
  transition: border-color .16s var(--ease), color .16s var(--ease);
}
.copy-btn:hover { border-color: var(--blue); color: var(--blue); }
.copy-btn[data-copied] { border-color: var(--green); color: var(--green); }
.copy-btn__hint { color: var(--green); }
.copy-btn__hint:empty { display: none; }

.site-footer__columns {
  display: grid;
  gap: clamp(22px, 3vw, 36px);
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
}
.footer-col__title {
  margin-bottom: 14px;
  padding-left: 10px;
  border-left: 2px solid var(--yellow);
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--dust);
}
.footer-col__list { display: grid; gap: 10px; list-style: none; }
.footer-col__list a {
  display: inline-block;
  padding-bottom: 1px;
  border-bottom: 1px solid transparent;
  color: var(--snow);
  font-size: 16px;
  text-decoration: none;
  transition: border-color .16s var(--ease), color .16s var(--ease);
}
.footer-col__list a:hover { border-bottom-color: var(--blue); color: var(--blue); }

.site-footer__bottom {
  max-width: var(--shell);
  margin-inline: auto;
  padding: 22px var(--gutter) 32px;
  border-top: 2px solid var(--line);
  display: grid;
  gap: 8px;
}
.footer-contact,
.footer-legal,
.footer-year {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--dust);
  line-height: 1.75;
}
.footer-year { color: rgba(154, 167, 188, .7); }

@media (min-width: 900px) {
  .site-footer__inner { grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr); }
  .site-footer__bottom { grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr); align-items: end; }
  .footer-contact { grid-column: 1 / -1; }
}

/* 14. 渐显（配合 data-reveal）---------------------------------------------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .32s var(--ease), transform .32s var(--ease);
}
[data-reveal][data-visible] { opacity: 1; transform: none; }

/* 15. 章节高亮状态（配合 data-section / data-section-link）------------------ */
[data-section-link] { transition: color .16s var(--ease), border-color .16s var(--ease); }
[data-section-link][data-active] { color: var(--yellow); border-color: var(--yellow); }
[data-section] { scroll-margin-top: 110px; }

/* 16. 可访问性偏好 ---------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  html { scroll-behavior: auto; }
  [data-reveal] { opacity: 1; transform: none; }
  .btn:hover, .card:hover { transform: none; }
}
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

/* 17. 窄屏微调 -------------------------------------------------------------- */
@media (max-width: 639px) {
  .brand__tagline { display: none; }
  .footer-brand__tagline { max-width: none; }
}
@media (max-width: 400px) {
  .nav-toggle__label { display: none; }
}