/* ══════════════════════════════════════════════════════════════
   华体汇网页 · 共享样式表 /assets/site.css
   夜空蓝底 · 草原青结构线 · 琥珀橙状态 · 1px 精密网格 · 编辑部节奏
   ══════════════════════════════════════════════════════════════ */

/* ── 1. 重置 ─────────────────────────────────────────────── */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;-webkit-tap-highlight-color:transparent;scroll-behavior:smooth}
body,figure,blockquote,dl,dd,h1,h2,h3,h4,h5,h6,p,pre,ul,ol{margin:0;padding:0}
ul,ol{list-style:none}
img,picture,svg,video{display:block;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;cursor:pointer}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}
hr{border:0;border-top:1px solid var(--rule-soft)}
::selection{background:var(--spark);color:#062018}

/* ── 2. 设计变量 ─────────────────────────────────────────── */
:root{
  /* 品牌色板 */
  --night:#0B1B33;
  --indigo:#142A4A;
  --grass:#2E7D6B;
  --spark:#35C6A8;
  --amber:#E8A33D;
  --saddle:#8A5A3B;
  --cream:#F5F1E8;
  --mist:#9AA7B4;
  --line:#3C4A5A;
  --ink:#0F3B33;

  /* 语义别名 */
  --bg:var(--night);
  --bg-raised:var(--indigo);
  --fg:var(--cream);
  --fg-soft:#C3CDD7;
  --fg-dim:var(--mist);
  --rule:rgba(60,74,90,.85);
  --rule-soft:rgba(60,74,90,.45);
  --accent:var(--spark);
  --state:var(--amber);

  /* 字体 */
  --font-display:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --font-body:"PingFang SC","Hiragino Sans GB","Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono","Courier New",monospace;

  /* 栅格与节奏 */
  --step:8px;
  --gutter:24px;
  --safe:5vw;
  --maxw:1280px;

  /* 动效 */
  --t-fast:160ms;
  --t-base:320ms;
  --ease-out:cubic-bezier(.22,.61,.36,1);
}

/* ── 3. 基础与中文排版 ───────────────────────────────────── */
body{
  min-height:100vh;
  display:flex;
  flex-direction:column;
  background-color:var(--night);
  background-image:
    radial-gradient(1200px 620px at 82% -12%,rgba(46,125,107,.24),rgba(11,27,51,0) 62%),
    radial-gradient(900px 480px at -10% 8%,rgba(138,90,59,.16),rgba(11,27,51,0) 60%),
    linear-gradient(180deg,#0B1B33 0%,#091729 100%);
  background-repeat:no-repeat;
  color:var(--fg);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.8;
  letter-spacing:.01em;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
#main-content{flex:1 0 auto;display:block}

h1,h2,h3,h4,h5{font-family:var(--font-display);font-weight:800;letter-spacing:-.01em;line-height:1.15;color:var(--fg)}
h1{font-size:clamp(30px,4.6vw,40px)}
h2{font-size:clamp(24px,3.2vw,32px)}
h3{font-size:24px}
h4{font-size:19px}
h5{font-size:16px}
p{max-width:48em}
strong{font-weight:700;color:#FFFFFF}
small{font-size:14px;color:var(--fg-dim)}
code,kbd,samp{font-family:var(--font-mono);font-size:14px;letter-spacing:.02em;color:var(--amber)}

:focus-visible{outline:2px solid var(--amber);outline-offset:3px}
a:focus-visible{outline:2px solid var(--amber);outline-offset:3px}

/* ── 4. 布局工具 ─────────────────────────────────────────── */
.container{width:min(100% - (var(--safe) * 2),var(--maxw));margin-inline:auto}

.grid{
  display:grid;
  gap:var(--gutter);
  grid-template-columns:repeat(12,minmax(0,1fr));
  align-items:start;
}
.span-3{grid-column:span 3}
.span-4{grid-column:span 4}
.span-5{grid-column:span 5}
.span-6{grid-column:span 6}
.span-7{grid-column:span 7}
.span-8{grid-column:span 8}
.span-9{grid-column:span 9}
.span-12{grid-column:span 12}

.section{position:relative;padding:clamp(48px,7vw,96px) 0}
.section--tight{padding:clamp(32px,5vw,56px) 0}
.section--raised{background:var(--indigo);border-top:1px solid var(--rule-soft);border-bottom:1px solid var(--rule-soft)}
.section--light{background:var(--cream);color:#22303D;border-top:1px solid rgba(15,59,51,.18);border-bottom:1px solid rgba(15,59,51,.18)}
.section--light h1,.section--light h2,.section--light h3,.section--light h4,.section--light h5{color:var(--ink)}
.section--light p{color:#2A3A48}
.section--light .eyebrow{color:var(--saddle)}
.section--light .note{color:#4A5A67}
.section--light .note__label{color:var(--grass)}

.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:10px 24px;
  padding-bottom:14px;
  margin-bottom:clamp(24px,3.6vw,40px);
  border-bottom:1px solid var(--rule-soft);
}
.section-head > *{margin:0}
.section--light .section-head{border-bottom-color:rgba(15,59,51,.22)}

.eyebrow{
  display:inline-block;
  font-family:var(--font-mono);
  font-size:12px;
  line-height:1.4;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--amber);
}

/* ── 5. 按钮 ─────────────────────────────────────────────── */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:13px 22px;
  border:1px solid transparent;
  border-radius:0;
  font-family:var(--font-display);
  font-weight:700;
  font-size:15px;
  line-height:1.2;
  letter-spacing:.01em;
  white-space:nowrap;
  transition:background-color var(--t-fast) linear,color var(--t-fast) linear,border-color var(--t-fast) linear,transform var(--t-fast) var(--ease-out);
}
.btn:hover{transform:translateY(-1px)}
.btn:active{transform:translateY(0)}
.btn--primary{background:var(--spark);border-color:var(--spark);color:#062018}
.btn--primary:hover{background:#5BD8BE;border-color:#5BD8BE}
.btn--ghost{background:rgba(20,42,74,.5);border-color:var(--line);color:var(--cream)}
.btn--ghost:hover{border-color:var(--spark);color:var(--spark);background:rgba(53,198,168,.08)}
.btn--sm{padding:9px 15px;font-size:13.5px}

/* ── 6. 基础组件 ─────────────────────────────────────────── */
.panel{
  background:var(--indigo);
  border:1px solid var(--rule-soft);
  padding:clamp(20px,3vw,32px);
}
.section--light .panel{background:#FFFDF7;border-color:rgba(15,59,51,.18)}

.card{
  position:relative;
  display:block;
  background:rgba(20,42,74,.55);
  border:1px solid var(--rule-soft);
  padding:clamp(18px,2.4vw,26px);
  transition:border-color var(--t-fast) linear,background-color var(--t-fast) linear,transform var(--t-base) var(--ease-out);
}
.card:hover,.card:focus-within{border-color:var(--spark);background:rgba(20,42,74,.78)}
.section--light .card{background:#FFFDF7;border-color:rgba(15,59,51,.2)}
.section--light .card:hover{border-color:var(--grass)}

.media-frame{
  position:relative;
  display:block;
  width:100%;
  overflow:hidden;
  aspect-ratio:16 / 9;
  background:linear-gradient(140deg,rgba(20,42,74,.95),rgba(11,27,51,.95));
  border:1px solid var(--rule-soft);
}
.media-frame > img,
.media-frame > svg{width:100%;height:100%;object-fit:cover}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--tall{aspect-ratio:3 / 5}
.media-frame--square{aspect-ratio:1 / 1}
.media-frame__label{
  position:absolute;
  left:0;
  bottom:0;
  max-width:100%;
  padding:7px 12px;
  background:rgba(11,27,51,.86);
  border-top:1px solid var(--rule-soft);
  border-right:1px solid var(--rule-soft);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--spark);
}
.section--light .media-frame{border-color:rgba(15,59,51,.24);background:linear-gradient(140deg,#EDE7DA,#DCE6E1)}
.section--light .media-frame__label{background:rgba(15,59,51,.88);border-color:transparent;color:var(--cream)}

.prose{max-width:42em;font-size:17px;line-height:1.8;color:var(--fg-soft)}
.prose p + p{margin-top:1.2em}
.prose h2{margin:2em 0 .6em;font-size:clamp(22px,2.6vw,28px)}
.prose h3{margin:1.6em 0 .5em}
.prose ul,.prose ol{margin:1em 0 0;padding-left:1.3em;list-style:disc}
.prose ol{list-style:decimal}
.prose li{margin-top:.5em}
.prose a{border-bottom:1px solid var(--grass);color:var(--cream)}
.prose a:hover{color:var(--spark);border-bottom-color:var(--spark)}
.section--light .prose{color:#2A3A48}
.section--light .prose a{color:var(--ink);border-bottom-color:var(--grass)}
.section--light .prose a:hover{color:var(--grass)}

.note{
  max-width:34ch;
  padding-left:16px;
  border-left:1px solid var(--grass);
  font-size:14px;
  line-height:1.7;
  color:var(--fg-dim);
}
.note__label{
  display:block;
  margin-bottom:6px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--spark);
}

.breadcrumb{
  padding-top:20px;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.02em;
  color:var(--fg-dim);
}
.breadcrumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:6px 10px}
.breadcrumb__item{display:inline-flex;align-items:center;gap:10px}
.breadcrumb__item + .breadcrumb__item::before{content:"/";color:var(--line)}
.breadcrumb__link{border-bottom:1px solid transparent;transition:color var(--t-fast) linear,border-color var(--t-fast) linear}
.breadcrumb__link:hover{color:var(--spark);border-bottom-color:var(--spark)}
.breadcrumb__item[aria-current="page"]{color:var(--cream)}

.chip{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border:1px solid var(--line);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--fg-dim);
}
.chip--accent{border-color:rgba(53,198,168,.55);color:var(--spark)}
.chip--state{border-color:rgba(232,163,61,.55);color:var(--amber)}

.timeline{display:grid;gap:28px;padding-left:26px;border-left:1px solid var(--rule-soft)}
.timeline__item{position:relative}
.timeline__item::before{
  content:"";
  position:absolute;
  left:-30px;
  top:9px;
  width:9px;
  height:9px;
  background:var(--night);
  border:1px solid var(--spark);
}
.timeline__meta{font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:var(--amber)}
.timeline__title{margin-top:6px;font-family:var(--font-display);font-weight:700;font-size:19px;line-height:1.3}
.timeline__text{margin-top:8px;font-size:16px;color:var(--fg-soft)}
.section--light .timeline{border-left-color:rgba(15,59,51,.24)}
.section--light .timeline__item::before{background:var(--cream)}
.section--light .timeline__meta{color:var(--saddle)}

.qa{border:1px solid var(--rule-soft);background:rgba(20,42,74,.38)}
.qa + .qa{margin-top:-1px}
.qa__summary{
  display:flex;
  align-items:center;
  gap:14px;
  padding:17px 20px;
  font-family:var(--font-display);
  font-weight:700;
  font-size:17px;
  line-height:1.4;
  cursor:pointer;
  list-style:none;
  transition:color var(--t-fast) linear,background-color var(--t-fast) linear;
}
.qa__summary::-webkit-details-marker{display:none}
.qa__summary:hover{color:var(--spark);background:rgba(53,198,168,.06)}
.qa__mark{
  position:relative;
  flex:0 0 auto;
  width:18px;
  height:18px;
  border:1px solid var(--line);
}
.qa__mark::before,.qa__mark::after{content:"";position:absolute;background:currentColor;color:var(--spark)}
.qa__mark::before{left:3px;right:3px;top:8px;height:1px}
.qa__mark::after{top:3px;bottom:3px;left:8px;width:1px;transition:transform var(--t-fast) linear,opacity var(--t-fast) linear}
.qa[open] .qa__summary{color:var(--spark)}
.qa[open] .qa__mark{border-color:var(--amber)}
.qa[open] .qa__mark::after{transform:scaleY(0);opacity:0}
.qa__body{padding:0 20px 20px 52px;font-size:16px;color:var(--fg-soft)}
.section--light .qa{background:#FFFDF7;border-color:rgba(15,59,51,.2)}
.section--light .qa__body{color:#3A4A57}

.aurora{position:absolute;inset:0;z-index:0;overflow:hidden;pointer-events:none}
.aurora::before,
.aurora::after{content:"";position:absolute;filter:blur(44px)}
.aurora::before{
  top:-20%;left:-12%;width:58%;height:140%;
  background:linear-gradient(100deg,rgba(53,198,168,.18),rgba(53,198,168,0) 62%);
  animation:aurora-drift 24s linear infinite alternate;
}
.aurora::after{
  bottom:-30%;right:-10%;width:52%;height:120%;
  background:linear-gradient(260deg,rgba(232,163,61,.13),rgba(46,125,107,0) 66%);
  animation:aurora-drift 24s linear infinite alternate-reverse;
}
@keyframes aurora-drift{
  from{transform:translate3d(0,0,0)}
  to{transform:translate3d(9%,0,0)}
}

.scroll-progress{
  position:fixed;
  top:0;
  left:0;
  z-index:90;
  width:0;
  height:2px;
  background:linear-gradient(90deg,#2E7D6B 0%,#35C6A8 55%,#E8A33D 100%);
  transition:width 120ms linear;
  pointer-events:none;
}

.js [data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity var(--t-base) var(--ease-out),transform var(--t-base) var(--ease-out);
}
.js [data-reveal].is-visible{opacity:1;transform:none}

/* ── 7. 页头（双层刊头） ─────────────────────────────────── */
.masthead{
  position:sticky;
  top:0;
  z-index:60;
  flex:0 0 auto;
  background:rgba(11,27,51,.94);
  -webkit-backdrop-filter:blur(10px) saturate(130%);
  backdrop-filter:blur(10px) saturate(130%);
  border-bottom:1px solid var(--rule);
}
.skip-link{
  position:absolute;
  left:16px;
  top:-120px;
  z-index:100;
  padding:10px 16px;
  background:var(--amber);
  color:#1B1200;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.04em;
  transition:top var(--t-fast) var(--ease-out);
}
.skip-link:focus{top:12px}

.mast-upper{
  background:linear-gradient(90deg,rgba(46,125,107,.16),rgba(11,27,51,0) 58%);
  border-bottom:1px solid var(--rule-soft);
}
.mast-upper__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  min-height:54px;
  padding:8px 0;
}
.mast-brand{display:flex;align-items:baseline;gap:12px;flex-wrap:wrap;min-width:0}
.mast-brand__name{
  display:inline-flex;
  align-items:center;
  font-family:var(--font-display);
  font-weight:800;
  font-size:16.5px;
  letter-spacing:-.01em;
  color:var(--cream);
}
.mast-brand__name::before{
  content:"";
  display:inline-block;
  width:8px;
  height:8px;
  margin-right:9px;
  background:var(--spark);
  transform:translateY(-1px);
}
.mast-brand__line{
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.02em;
  color:var(--mid-mist,var(--mist));
  white-space:nowrap;
}
.mast-utility{display:flex;align-items:center;gap:16px;flex:0 0 auto}
.mast-utility__link{
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.02em;
  color:var(--mist);
  padding-bottom:2px;
  border-bottom:1px solid transparent;
  transition:color var(--t-fast) linear,border-color var(--t-fast) linear;
}
.mast-utility__link:hover{color:var(--spark);border-bottom-color:var(--spark)}

.mast-lower{position:relative;border-top:1px solid rgba(60,74,90,.2)}
.mast-lower__inner{display:flex;align-items:center;gap:20px;min-height:58px}
.mast-lower__meta{
  flex:0 0 auto;
  margin-left:auto;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.12em;
  color:var(--line);
  white-space:nowrap;
}

.site-nav{flex:1 1 auto;min-width:0}
.site-nav__list{
  display:flex;
  align-items:center;
  gap:min(2.4vw,30px);
  overflow-x:auto;
  scrollbar-width:none;
  -ms-overflow-style:none;
}
.site-nav__list::-webkit-scrollbar{display:none}
.site-nav__item{flex:0 0 auto}
.site-nav__link{
  position:relative;
  display:inline-flex;
  align-items:center;
  gap:7px;
  padding:10px 2px 12px;
  font-family:var(--font-display);
  font-weight:700;
  font-size:15.5px;
  letter-spacing:-.01em;
  color:var(--cream);
  white-space:nowrap;
  transition:color var(--t-fast) linear;
}
.site-nav__num{
  font-family:var(--font-mono);
  font-size:10.5px;
  font-weight:400;
  letter-spacing:.04em;
  color:var(--line);
  transition:color var(--t-fast) linear;
}
.site-nav__link::after{
  content:"";
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  height:2px;
  background:var(--spark);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform var(--t-base) var(--ease-out),background-color var(--t-fast) linear;
}
.site-nav__link:hover{color:var(--spark)}
.site-nav__link:hover .site-nav__num{color:var(--grass)}
.site-nav__link:hover::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:var(--cream)}
.site-nav__link[aria-current="page"] .site-nav__num{color:var(--amber)}
.site-nav__link[aria-current="page"]::after{transform:scaleX(1);background:var(--amber)}

.nav-toggle{
  display:none;
  align-items:center;
  gap:10px;
  padding:9px 13px;
  border:1px solid var(--line);
  background:rgba(20,42,74,.6);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--cream);
  transition:border-color var(--t-fast) linear,color var(--t-fast) linear;
}
.nav-toggle:hover{border-color:var(--spark);color:var(--spark)}
.nav-toggle__bars{position:relative;display:inline-block;width:16px;height:10px}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;
  right:0;
  height:1px;
  background:currentColor;
  transition:transform var(--t-fast) var(--ease-out),top var(--t-fast) linear,bottom var(--t-fast) linear;
}
.nav-toggle__bars::before{top:0}
.nav-toggle__bars::after{bottom:0}
.nav-toggle[aria-expanded="true"]{border-color:var(--amber);color:var(--amber)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{top:50%;transform:rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{bottom:calc(50% - 1px);transform:rotate(-45deg)}
.nav-toggle__text{line-height:1}

/* ── 8. 页脚 ─────────────────────────────────────────────── */
.site-foot{
  position:relative;
  flex:0 0 auto;
  margin-top:clamp(40px,7vw,88px);
  background:linear-gradient(180deg,rgba(20,42,74,.35) 0%,#081426 100%);
  border-top:1px solid var(--rule);
}
.site-foot::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:1px;
  background:linear-gradient(90deg,rgba(53,198,168,0),var(--spark) 45%,rgba(232,163,61,.8) 100%);
  opacity:.55;
}
.foot-top{
  display:grid;
  grid-template-columns:minmax(240px,1.05fr) 2.2fr;
  gap:clamp(28px,5vw,72px);
  padding:clamp(40px,6vw,72px) 0 clamp(28px,4vw,48px);
}
.foot-brand__name{
  font-family:var(--font-display);
  font-weight:800;
  font-size:22px;
  letter-spacing:-.01em;
  color:var(--cream);
}
.foot-brand__line{
  margin-top:8px;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.02em;
  color:var(--spark);
}
.foot-brand__note{margin-top:16px;max-width:34ch;font-size:15px;line-height:1.7;color:var(--fg-soft)}
.foot-brand__addr{
  margin-top:12px;
  max-width:34ch;
  padding-left:12px;
  border-left:1px solid var(--saddle);
  font-size:14px;
  line-height:1.7;
  color:var(--mist);
}
.foot-brand__cta{margin-top:22px}

.foot-cols{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(20px,3vw,36px)}
.foot-col__title{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--amber);
}
.foot-col__list{margin-top:16px;display:grid;gap:11px}
.foot-col__link{
  display:inline-block;
  font-size:15px;
  color:var(--fg-soft);
  border-bottom:1px solid transparent;
  transition:color var(--t-fast) linear,border-color var(--t-fast) linear;
}
.foot-col__link:hover{color:var(--spark);border-bottom-color:var(--spark)}

.foot-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:14px 28px;
  padding:22px 0;
  border-top:1px solid var(--rule-soft);
}
.foot-contact{
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.02em;
  color:var(--mist);
}
.foot-legal{display:flex;flex-wrap:wrap;gap:18px}
.foot-legal__link{
  font-size:14px;
  color:var(--mist);
  border-bottom:1px solid transparent;
  transition:color var(--t-fast) linear,border-color var(--t-fast) linear;
}
.foot-legal__link:hover{color:var(--spark);border-bottom-color:var(--spark)}

.foot-base{background:rgba(8,20,38,.92);border-top:1px solid var(--rule-soft)}
.foot-base__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:8px 20px;
  padding:15px 0;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.02em;
  color:#7C8B99;
}
.foot-icp{font-family:var(--font-mono)}
.foot-copy{font-family:var(--font-mono)}

/* ── 9. 响应式 ───────────────────────────────────────────── */
@media (max-width:1024px){
  .grid{grid-template-columns:repeat(8,minmax(0,1fr))}
  .span-3,.span-4{grid-column:span 4}
  .span-5,.span-6,.span-7,.span-8,.span-9,.span-12{grid-column:span 8}
  .foot-top{grid-template-columns:1fr;gap:40px}
  .site-nav__list{gap:22px}
}

@media (max-width:860px){
  .mast-upper__inner{flex-wrap:wrap;gap:10px;padding:10px 0}
  .mast-brand__line{white-space:normal}
  .mast-utility{width:100%;justify-content:space-between}
  .mast-lower__inner{gap:12px;min-height:56px}
  .mast-lower__meta{display:none}
  .nav-toggle{display:inline-flex;flex:0 0 auto}

  .site-nav{
    position:absolute;
    left:0;
    right:0;
    top:100%;
    display:none;
    background:rgba(20,42,74,.985);
    border-top:1px solid var(--rule-soft);
    border-bottom:1px solid var(--rule);
    box-shadow:0 28px 52px rgba(0,0,0,.5);
    max-height:72vh;
    overflow-y:auto;
    padding:0 var(--safe);
  }
  .site-nav[data-open]{display:block;animation:nav-drop var(--t-base) var(--ease-out) both}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0;overflow:visible;padding:4px 0 14px}
  .site-nav__item{width:100%;border-bottom:1px solid var(--rule-soft)}
  .site-nav__item:last-child{border-bottom:0}
  .site-nav__link{display:flex;width:100%;padding:15px 0;font-size:17px;gap:12px}
  .site-nav__num{font-size:11px;color:var(--grass)}
  .site-nav__link::after{display:none}
  .site-nav__link[aria-current="page"]{color:var(--spark);padding-left:12px;border-left:2px solid var(--amber)}
  @keyframes nav-drop{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:none}}
}

@media (max-width:640px){
  body{font-size:16px}
  .grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}
  .span-3,.span-4,.span-5,.span-6,.span-7,.span-8,.span-9,.span-12{grid-column:span 4}
  .foot-cols{grid-template-columns:1fr;gap:26px}
  .foot-bottom{flex-direction:column;align-items:flex-start;gap:14px}
  .foot-brand__cta{width:100%}
  .btn{padding:12px 18px}
  .btn--sm{padding:8px 13px;font-size:13px}
  .note{max-width:none}
  .qa__body{padding-left:20px}
}

/* ── 10. 动效可访问性 ────────────────────────────────────── */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important}
  .aurora::before,.aurora::after{animation:none;opacity:.1}
  .js [data-reveal]{opacity:1;transform:none;transition:none}
  .btn:hover{transform:none}
}