/* ============================================================
   K1体育APP · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 页头 / 页脚 / 通用组件
   夜间战术数据屏 + 复古出版排版
   ============================================================ */

/* ---------- 1. 变量 ---------- */
:root{
  --ink-deep:#0B1B2B;
  --ink-panel:#12293F;
  --paper-cream:#F2EDE4;
  --paper-dim:#E3DACB;
  --signal-green:#00E676;
  --green-deep:#00A152;
  --amber-node:#FFC107;
  --rust-orange:#D0552B;
  --black-brown:#241E1A;
  --mist-gray:#93A4B4;
  --line-hair:#2A4159;

  --wrap:1320px;
  --gutter:clamp(1rem,3vw,2.5rem);
  --header-h:68px;
  --radius:2px;

  --font-display:'Archivo Narrow','HarmonyOS Sans SC','Noto Sans SC',sans-serif;
  --font-mono:'JetBrains Mono','IBM Plex Mono',ui-monospace,SFMono-Regular,Menlo,monospace;
  --font-body:system-ui,'Noto Sans SC','Source Han Sans SC',sans-serif;

  --step-cover:clamp(2.6rem,6vw,5.2rem);
  --step-section:clamp(1.5rem,2.6vw,2.2rem);
  --step-body:1rem;
  --step-note:.8125rem;
  --step-index:.75rem;

  --ease:ease-out;
  --dur:220ms;
}

/* ---------- 2. Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--header-h) + 14px);
}
body{
  margin:0;
  min-height:100vh;
  overflow-x:hidden;
  background:var(--ink-deep);
  color:var(--paper-cream);
  font-family:var(--font-body);
  font-size:var(--step-body);
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4,h5,h6,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0}
img,svg,video{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit}
table{border-collapse:collapse}
hr{border:0;border-top:1px solid var(--line-hair);margin:0}
:focus-visible{outline:2px solid var(--signal-green);outline-offset:2px}

#main-content{display:block;padding-top:var(--header-h)}

/* ---------- 3. 中文排版与字级 ---------- */
h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:700;
  letter-spacing:-.02em;
  line-height:1.15;
  text-transform:uppercase;
}
p{max-width:62ch}
.mono{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-feature-settings:"tnum" 1;
}
.index-label{
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-gray);
}
.note{font-size:var(--step-note);color:var(--mist-gray);max-width:58ch}
.lede{font-size:1.0625rem;line-height:1.8;color:#CBD6E1;max-width:56ch}
.display-xl{font-size:var(--step-cover);font-weight:200;letter-spacing:-.03em;line-height:1.02}
.display-xl strong{font-weight:800}

/* ---------- 4. 布局骨架 ---------- */
.wrap{
  width:100%;
  max-width:var(--wrap);
  margin:0 auto;
  padding-left:var(--gutter);
  padding-right:var(--gutter);
}
.section{padding:clamp(2.5rem,6vw,5rem) 0}
.section--tight{padding:clamp(1.5rem,3.5vw,2.75rem) 0}
.stack{display:grid;gap:clamp(.75rem,2vw,1.5rem)}
.cover{margin-top:calc(-1 * var(--header-h));position:relative}

.grid-12{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(.75rem,1.6vw,1.25rem)}
.col-3{grid-column:span 3}
.col-4{grid-column:span 4}
.col-5{grid-column:span 5}
.col-6{grid-column:span 6}
.col-7{grid-column:span 7}
.col-8{grid-column:span 8}
.col-9{grid-column:span 9}
.col-12{grid-column:span 12}

.bento{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(.75rem,1.5vw,1.15rem)}

.layout-axis{
  display:grid;
  grid-template-columns:minmax(0,3fr) minmax(0,9fr);
  gap:clamp(1rem,2.5vw,2.25rem);
  align-items:start;
}
.axis-rail{
  position:sticky;
  top:calc(var(--header-h) + 1.25rem);
  align-self:start;
}
.axis-rail.is-axis-hidden{display:none}

/* ---------- 5. 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.5rem;
  padding:.55rem 1rem;
  border:1px solid var(--line-hair);
  border-radius:var(--radius);
  background:transparent;
  color:var(--paper-cream);
  font-family:var(--font-display);
  font-size:var(--step-note);
  font-weight:700;
  letter-spacing:.1em;
  text-transform:uppercase;
  cursor:pointer;
  transition:background-color 160ms var(--ease),color 160ms var(--ease),border-color 160ms var(--ease);
}
.btn:hover{border-color:var(--mist-gray)}
.btn-signal{
  background:var(--signal-green);
  border-color:var(--signal-green);
  color:#06251A;
}
.btn-signal:hover{background:#4DFFA0;border-color:#4DFFA0;color:#06251A}
.btn-ghost{color:var(--mist-gray)}
.btn-ghost:hover{color:var(--paper-cream)}
.btn-block{width:100%}

/* ---------- 6. 页头 ---------- */
.skip-link{
  position:absolute;
  top:0;
  left:0;
  z-index:140;
  transform:translateY(-150%);
  padding:.6rem 1rem;
  background:var(--signal-green);
  color:#06251A;
  font-family:var(--font-mono);
  font-size:var(--step-note);
  text-decoration:none;
  transition:transform 160ms var(--ease);
}
.skip-link:focus{transform:translateY(0)}

.site-header{
  position:fixed;
  top:0;left:0;right:0;
  z-index:90;
  background:transparent;
  border-bottom:1px solid transparent;
  transition:background-color 120ms var(--ease),border-color 120ms var(--ease);
}
.site-header::before{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background:linear-gradient(180deg,rgba(11,27,43,.86),rgba(11,27,43,0));
  transition:opacity 120ms var(--ease);
}
.site-header.is-solid{background:var(--ink-deep);border-bottom-color:var(--line-hair)}
.site-header.is-solid::before{opacity:0}

.header-inner{
  position:relative;
  z-index:1;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:clamp(.75rem,2vw,2rem);
  width:100%;
  max-width:var(--wrap);
  margin:0 auto;
  padding:0 var(--gutter);
  height:var(--header-h);
}

.brand{display:inline-flex;align-items:center;gap:.6rem;flex:0 0 auto}
.brand-mark{
  display:grid;
  place-items:center;
  width:34px;height:34px;
  border:1px solid var(--signal-green);
  color:var(--signal-green);
  font-family:var(--font-mono);
  font-size:.8125rem;
  letter-spacing:.04em;
}
.brand-text{display:flex;flex-direction:column;line-height:1.15}
.brand-name{
  font-family:var(--font-display);
  font-weight:800;
  font-size:1.0625rem;
  letter-spacing:-.01em;
  text-transform:uppercase;
}
.brand-line{font-size:var(--step-index);letter-spacing:.06em;color:var(--mist-gray)}

.site-nav{
  display:flex;
  justify-content:center;
  flex:1 1 auto;
  min-width:0;
}
.nav-list{display:flex;align-items:center;gap:clamp(.5rem,1.4vw,1.3rem)}
.nav-link{
  position:relative;
  display:inline-block;
  padding:.35rem 0;
  font-size:var(--step-index);
  letter-spacing:.12em;
  color:var(--mist-gray);
  transition:color 160ms var(--ease);
}
.nav-link::after{
  content:"";
  position:absolute;
  left:0;right:0;bottom:-2px;
  height:1px;
  background:var(--signal-green);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform 180ms var(--ease);
}
.nav-link:hover,.nav-link:focus-visible{color:var(--paper-cream)}
.nav-link:hover::after,.nav-link:focus-visible::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--signal-green)}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}
.nav-cta-item{display:none}
.nav-cta{width:100%}

.header-tools{display:flex;align-items:center;gap:.55rem;flex:0 0 auto}
.round-readout{display:inline-flex;align-items:baseline;gap:.4rem;white-space:nowrap}
.round-readout-key{font-size:var(--step-index);letter-spacing:.12em;color:var(--mist-gray)}
.round-readout-val{font-size:var(--step-note);color:var(--signal-green)}

.axis-toggle,.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:.45rem;
  padding:.45rem .6rem;
  border:1px solid var(--line-hair);
  border-radius:var(--radius);
  background:transparent;
  color:var(--mist-gray);
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.1em;
  cursor:pointer;
  transition:color 160ms var(--ease),border-color 160ms var(--ease);
}
.axis-toggle:hover,.nav-toggle:hover{color:var(--paper-cream);border-color:var(--mist-gray)}
.axis-toggle[aria-expanded="true"],
.nav-toggle[aria-expanded="true"]{color:var(--signal-green);border-color:var(--signal-green)}

.nav-toggle{display:none}
.nav-toggle-bars{position:relative;display:block;width:16px;height:2px;background:currentColor}
.nav-toggle-bars::before,.nav-toggle-bars::after{
  content:"";
  position:absolute;left:0;
  width:16px;height:2px;
  background:currentColor;
  transition:transform 180ms var(--ease);
}
.nav-toggle-bars::before{top:-5px}
.nav-toggle-bars::after{top:5px}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars{background:transparent}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::before{transform:translateY(5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::after{transform:translateY(-5px) rotate(-45deg)}
.nav-toggle-label{font-size:var(--step-index);letter-spacing:.1em}

.read-progress{
  position:absolute;
  left:0;bottom:0;
  z-index:2;
  width:100%;height:2px;
  background:var(--signal-green);
  transform:scaleX(0);
  transform-origin:left center;
  will-change:transform;
}

/* ---------- 7. 页脚 ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(3rem,8vw,6rem);
  background:var(--ink-deep);
  border-top:1px solid var(--line-hair);
}
.footer-rule{
  height:2px;
  background:linear-gradient(90deg,
    var(--signal-green) 0 96px,
    var(--amber-node) 96px 150px,
    var(--line-hair) 150px 100%);
}
.footer-inner{
  width:100%;
  max-width:var(--wrap);
  margin:0 auto;
  padding:clamp(2rem,5vw,3.5rem) var(--gutter) clamp(1.25rem,3vw,2rem);
}
.footer-top{
  display:grid;
  grid-template-columns:minmax(260px,1.15fr) minmax(0,2.4fr);
  gap:clamp(1.5rem,4vw,3rem);
  padding-bottom:clamp(1.5rem,3vw,2.25rem);
  border-bottom:1px solid var(--line-hair);
}
.footer-brand{display:grid;gap:.85rem;align-content:start}
.brand-footer .brand-text{line-height:1.2}
.footer-tagline{font-size:.9375rem;color:#CBD6E1;max-width:34ch}
.footer-note{font-size:var(--step-note);color:var(--mist-gray);max-width:38ch}

.footer-cols{
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:1.25rem;
}
.footer-col-title{
  padding-top:.7rem;
  border-top:1px solid var(--line-hair);
  font-family:var(--font-mono);
  font-size:var(--step-index);
  font-weight:400;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-gray);
}
.footer-links{display:grid;gap:.5rem;margin-top:.85rem}
.footer-links a{
  display:inline-block;
  font-size:.9375rem;
  color:var(--paper-cream);
  transition:color 160ms var(--ease),transform 160ms var(--ease);
}
.footer-links a:hover{color:var(--signal-green)}

.footer-contact{
  display:grid;
  gap:.5rem;
  padding:clamp(1.25rem,2.5vw,1.75rem) 0;
  border-bottom:1px solid var(--line-hair);
}
.footer-contact-line{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.6rem;
  font-size:.9375rem;
  max-width:none;
}
.contact-key{
  min-width:5.5rem;
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.12em;
  color:var(--mist-gray);
  text-transform:uppercase;
}
.contact-val{color:var(--paper-cream)}
.copy-btn{
  padding:.2rem .5rem;
  border:1px solid var(--line-hair);
  border-radius:var(--radius);
  background:transparent;
  color:var(--mist-gray);
  font-family:var(--font-mono);
  font-size:.6875rem;
  letter-spacing:.1em;
  cursor:pointer;
  transition:color 160ms var(--ease),border-color 160ms var(--ease);
}
.copy-btn:hover{color:var(--signal-green);border-color:var(--signal-green)}
.copy-btn.is-done{color:var(--signal-green);border-color:var(--signal-green)}
.footer-contact-note{font-size:var(--step-note);color:var(--mist-gray);max-width:none}

.footer-base{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:.75rem;
  padding-top:clamp(1rem,2vw,1.5rem);
}
.footer-legal,.footer-copy{
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.1em;
  color:var(--mist-gray);
  max-width:none;
}

/* ---------- 8. 面包屑与章节题头 ---------- */
.breadcrumbs{padding:clamp(1rem,2vw,1.5rem) 0 0}
.breadcrumb-list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.5rem;
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-gray);
}
.breadcrumb-list li{display:inline-flex;align-items:center;gap:.5rem}
.breadcrumb-list li:not(:first-child)::before{content:"/";color:var(--rust-orange)}
.breadcrumb-list a:hover{color:var(--paper-cream)}

.section-head{
  display:flex;
  align-items:baseline;
  gap:1rem;
  padding-bottom:.75rem;
  margin-bottom:clamp(1rem,2.5vw,2rem);
  border-bottom:1px solid var(--line-hair);
}
.section-index{
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.14em;
  color:var(--rust-orange);
  transition:color 200ms var(--ease);
}
.section-title{
  font-family:var(--font-display);
  font-size:var(--step-section);
  font-weight:700;
  letter-spacing:-.02em;
  text-transform:uppercase;
}
[data-section].is-active .section-index{color:var(--signal-green)}

/* ---------- 9. 面板 / 卡片 / 玻璃层 ---------- */
.panel{
  background:var(--ink-panel);
  border:1px solid var(--line-hair);
  padding:clamp(1rem,2vw,1.5rem);
}
.panel--glass{
  background:rgba(18,41,63,.55);
  -webkit-backdrop-filter:blur(10px) saturate(120%);
  backdrop-filter:blur(10px) saturate(120%);
  border-color:rgba(147,164,180,.22);
}
.panel--paper{
  background:var(--paper-cream);
  border-color:var(--paper-dim);
  color:var(--black-brown);
}
.card{
  display:flex;
  flex-direction:column;
  background:var(--ink-panel);
  border:1px solid var(--line-hair);
  transition:border-color 200ms var(--ease),transform 200ms var(--ease);
}
.card:hover{border-color:#3B5A78}
.card:focus-within{border-color:var(--signal-green)}
.card-head{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:.75rem;
  padding:.9rem 1rem;
  border-bottom:1px solid var(--line-hair);
}
.card-title{
  font-family:var(--font-display);
  font-size:1.0625rem;
  font-weight:700;
  letter-spacing:-.01em;
  text-transform:uppercase;
}
.card-body{padding:1rem;display:grid;gap:.6rem;align-content:start}

.badge{
  display:inline-flex;
  align-items:center;
  gap:.35rem;
  padding:.15rem .45rem;
  border:1px solid var(--line-hair);
  border-radius:var(--radius);
  font-family:var(--font-mono);
  font-size:.6875rem;
  letter-spacing:.08em;
  text-transform:uppercase;
  color:var(--mist-gray);
}
.badge--green{color:var(--signal-green);border-color:rgba(0,230,118,.45)}
.badge--amber{color:var(--amber-node);border-color:rgba(255,193,7,.45)}
.badge--rust{color:var(--rust-orange);border-color:rgba(208,85,43,.5)}

/* ---------- 10. 数据块与表格 ---------- */
.stat-row{display:flex;flex-wrap:wrap;gap:clamp(1rem,3vw,2.5rem)}
.stat{display:grid;gap:.25rem;align-content:start}
.stat-value{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-size:clamp(1.75rem,3.4vw,2.75rem);
  font-weight:500;
  line-height:1;
  color:var(--paper-cream);
}
.stat-value--signal{color:var(--signal-green)}
.stat-value--amber{color:var(--amber-node)}
.stat-label{font-size:var(--step-index);letter-spacing:.12em;text-transform:uppercase;color:var(--mist-gray)}

.data-table{width:100%;font-size:.9375rem}
.data-table caption{
  caption-side:top;
  text-align:left;
  padding-bottom:.6rem;
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-gray);
}
.data-table th,.data-table td{
  padding:.7rem .75rem;
  text-align:left;
  vertical-align:top;
  border-bottom:1px solid var(--line-hair);
}
.data-table thead th{
  background:var(--ink-panel);
  font-family:var(--font-display);
  font-size:var(--step-index);
  font-weight:700;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-gray);
}
.data-table tbody tr:nth-child(odd){background:rgba(18,41,63,.5)}
.data-table--paper{
  background:var(--paper-cream);
  color:var(--black-brown);
}
.data-table--paper th,.data-table--paper td{border-bottom-color:var(--paper-dim)}
.data-table--paper thead th{background:var(--paper-dim);color:var(--black-brown)}
.data-table--paper tbody tr:nth-child(odd){background:rgba(227,218,203,.55)}

/* ---------- 11. 时间线 ---------- */
.timeline{
  position:relative;
  display:grid;
  margin-left:.35rem;
  border-left:1px solid var(--line-hair);
}
.timeline-item{position:relative;padding:0 0 1.6rem 1.25rem}
.timeline-item:last-child{padding-bottom:0}
.timeline-marker{
  position:absolute;
  left:-4.5px;top:.55rem;
  width:8px;height:8px;
  border-radius:50%;
  background:var(--rust-orange);
}
.timeline-item--signal .timeline-marker{
  background:var(--signal-green);
  box-shadow:0 0 0 4px rgba(0,230,118,.16);
}
.timeline-item--amber .timeline-marker{background:var(--amber-node)}
.timeline-time{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-size:var(--step-index);
  letter-spacing:.06em;
  color:var(--mist-gray);
}
.timeline-body{margin-top:.2rem}

/* ---------- 12. 全宽抢断计数条 ---------- */
.signal-bar{
  position:relative;
  display:flex;
  align-items:center;
  gap:clamp(1rem,3vw,2.5rem);
  width:100%;
  height:clamp(56px,7vw,96px);
  padding:0 var(--gutter);
  overflow:hidden;
  background:var(--ink-panel);
  border-top:1px solid var(--line-hair);
  border-bottom:1px solid var(--line-hair);
}
.signal-bar::after{
  content:"";
  position:absolute;
  top:0;bottom:0;
  left:-25%;
  width:22%;
  background:linear-gradient(90deg,rgba(0,230,118,0),rgba(0,230,118,.3),rgba(0,230,118,0));
  animation:signal-sweep 1.6s var(--ease) 1 both;
}
@keyframes signal-sweep{
  from{left:-25%}
  to{left:105%}
}
.signal-bar-figure{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-size:clamp(1.5rem,3vw,2.25rem);
  line-height:1;
  color:var(--signal-green);
}
.signal-bar-label{
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-gray);
}

/* ---------- 13. 图片容器 ---------- */
.media-frame{
  position:relative;
  display:block;
  overflow:hidden;
  border:1px solid var(--line-hair);
  background:var(--ink-panel);
  aspect-ratio:16/9;
}
.media-frame--wide{aspect-ratio:21/9}
.media-frame--square{aspect-ratio:1/1}
.media-frame--portrait{aspect-ratio:3/4}
.media-frame img{width:100%;height:100%;object-fit:cover}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background:linear-gradient(180deg,rgba(11,27,43,0) 42%,rgba(11,27,43,.74));
}
.media-caption{
  margin-top:.5rem;
  font-size:var(--step-note);
  color:var(--mist-gray);
}

/* ---------- 14. 长文层 ---------- */
.prose{
  max-width:74ch;
  padding:clamp(1.5rem,4vw,3rem);
  background:var(--paper-cream);
  color:var(--black-brown);
  line-height:1.8;
}
.prose h2{
  margin:1.75em 0 .5em;
  font-size:var(--step-section);
  color:var(--black-brown);
}
.prose h2:first-child{margin-top:0}
.prose h3{
  margin:1.4em 0 .4em;
  font-size:1.125rem;
  color:var(--black-brown);
}
.prose p{margin-bottom:1em;max-width:none}
.prose ul{list-style:disc;padding-left:1.25em;margin-bottom:1em}
.prose ol{list-style:decimal;padding-left:1.35em;margin-bottom:1em}
.prose li{margin-bottom:.35em}
.prose a{
  color:var(--green-deep);
  font-weight:600;
  text-decoration:underline;
  text-underline-offset:3px;
}
.prose strong{color:var(--black-brown);font-weight:700}
.prose code{
  font-family:var(--font-mono);
  font-size:.875em;
  background:var(--paper-dim);
  padding:.1em .35em;
}

/* ---------- 15. 筛选芯片 ---------- */
.chip-group{display:flex;flex-wrap:wrap;gap:.4rem}
.chip{
  appearance:none;
  padding:.4rem .7rem;
  border:1px solid var(--line-hair);
  border-radius:var(--radius);
  background:transparent;
  color:var(--mist-gray);
  font-family:var(--font-mono);
  font-size:var(--step-index);
  letter-spacing:.1em;
  cursor:pointer;
  transition:color 160ms var(--ease),border-color 160ms var(--ease),background-color 160ms var(--ease);
}
.chip:hover{color:var(--paper-cream);border-color:var(--mist-gray)}
.chip[aria-pressed="true"]{
  background:rgba(0,230,118,.14);
  border-color:var(--signal-green);
  color:var(--signal-green);
}

/* ---------- 16. 显现动效 ---------- */
.js [data-reveal]{
  opacity:0;
  transform:translateY(10px);
  transition:opacity 240ms var(--ease),transform 240ms var(--ease);
}
.js [data-reveal].is-visible{opacity:1;transform:none}

/* ---------- 17. 响应式 ---------- */
@media (max-width:1280px){
  .round-readout-key{display:none}
}
@media (max-width:1180px){
  .header-cta{display:none}
  .nav-list{gap:.7rem}
  .nav-link{letter-spacing:.08em}
}
@media (max-width:1080px){
  :root{--header-h:60px}

  .nav-toggle{display:inline-flex}

  .site-nav{
    position:fixed;
    left:0;right:0;
    top:var(--header-h);
    display:block;
    flex:none;
    max-height:calc(100vh - var(--header-h));
    overflow-y:auto;
    padding:1rem var(--gutter) 1.5rem;
    background:var(--ink-deep);
    border-bottom:1px solid var(--line-hair);
    opacity:0;
    visibility:hidden;
    transform:translateY(-8px);
    pointer-events:none;
    transition:opacity 200ms var(--ease),transform 200ms var(--ease),visibility 200ms var(--ease);
  }
  .site-nav[data-open]{
    opacity:1;
    visibility:visible;
    transform:none;
    pointer-events:auto;
  }
  .nav-list{flex-direction:column;align-items:stretch;gap:0}
  .nav-link{
    display:block;
    padding:.85rem 0;
    font-size:.9375rem;
    letter-spacing:.04em;
    border-bottom:1px solid var(--line-hair);
  }
  .nav-link::after{display:none}
  .nav-link[aria-current="page"]{color:var(--signal-green)}
  .nav-cta-item{display:block;padding-top:1.1rem}
  .nav-cta{padding:.75rem 1rem}

  .layout-axis{grid-template-columns:minmax(0,1fr)}
  .axis-rail{
    position:static;
    top:auto;
    display:none;
    width:100%;
  }
  .axis-rail.is-axis-open{display:block}

  .footer-top{grid-template-columns:minmax(0,1fr)}
  .footer-cols{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:900px){
  .col-3,.col-4,.col-5,.col-6,.col-7,.col-8,.col-9{grid-column:span 12}
}
@media (max-width:600px){
  .brand-line{display:none}
  .axis-toggle{display:none}
  .footer-cols{grid-template-columns:minmax(0,1fr);gap:1rem}
  .footer-base{flex-direction:column;align-items:flex-start}
  .contact-key{min-width:4.5rem}
  .stat-row{gap:1.25rem}
}

/* ---------- 18. 动效降级 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .signal-bar::after{display:none}
  .js [data-reveal]{opacity:1;transform:none}
}