/* ===========================================================
   777老虎游 · /assets/site.css
   共享层：reset / tokens / 排版 / 头部 / 页脚 / 通用组件
   =========================================================== */

/* ---------- 1. tokens ---------- */
:root{
  --ink:#07070B;
  --panel:#111118;
  --panel-2:#0C0C12;
  --line:#1E1E2A;
  --gold:#F5C542;
  --gold-hi:#FFE49A;
  --gold-deep:#8C6A12;
  --violet:#7A4BFF;
  --ruby:#E23A63;
  --cyan:#4FD8E8;
  --paper:#E9E7E0;
  --muted:#9C99AC;

  --bw:3px;
  --shadow-hard:8px 8px 0 var(--line);
  --shadow-gold:8px 8px 0 var(--gold-deep);

  --shell:1240px;
  --gutter:clamp(16px,4vw,40px);
  --sec:clamp(40px,6vw,88px);

  --font-display:'DIN Alternate','Bahnschrift','HarmonyOS Sans',system-ui,sans-serif;
  --font-title:'Archivo Black','Noto Sans SC','PingFang SC',system-ui,sans-serif;
  --font-body:'Inter','PingFang SC','Microsoft YaHei',system-ui,sans-serif;
  --font-mono:'IBM Plex Mono','SFMono-Regular',ui-monospace,monospace;

  --t-press:180ms;
  --t-expand:240ms;
  --t-collapse:200ms;
}

/* ---------- 2. reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  text-size-adjust:100%;
  scroll-behavior:smooth;
}
body{
  margin:0;
  background:var(--ink);
  color:var(--paper);
  font-family:var(--font-body);
  font-size:16px;
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
img,svg,video,picture{max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
h1,h2,h3,h4{font-family:var(--font-title);font-weight:800;line-height:1.1;color:var(--paper);margin:0}
p{margin:0 0 1em}
a{color:inherit}
ul,ol{margin:0;padding:0}
::selection{background:var(--gold);color:var(--ink)}
:focus-visible{outline:3px solid var(--cyan);outline-offset:3px}

/* ---------- 3. 布局基础 ---------- */
.shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.section{padding-block:var(--sec)}
.section__kicker{margin:0 0 10px}
.section__title{
  font-size:clamp(26px,4.4vw,52px);
  letter-spacing:.01em;
  margin:0;
  text-wrap:balance;
}
.section__lead{
  max-width:62ch;
  margin-top:16px;
  color:var(--muted);
  font-size:16.5px;
}
.grid{display:grid;gap:clamp(16px,2.4vw,32px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--12{grid-template-columns:repeat(12,minmax(0,1fr))}
.band{
  background:var(--panel);
  border-block:var(--bw) solid var(--line);
  padding-block:clamp(28px,4vw,48px);
}
.band--gold{
  background:var(--gold);
  color:var(--ink);
  border-block-color:var(--gold-deep);
}
.band--gold .section__lead,.band--gold .eyebrow{color:#3B2C05}

/* ---------- 4. 字体寄存器 ---------- */
.display-num{
  font-family:var(--font-display);
  font-weight:200;
  font-size:clamp(72px,18vw,200px);
  line-height:.86;
  letter-spacing:-.04em;
  color:var(--gold);
  margin:0;
  font-variant-numeric:tabular-nums;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.18em;
  color:var(--gold);
  margin:0;
}
.eyebrow::before{
  content:"";
  width:18px;
  height:3px;
  background:var(--gold);
  flex:0 0 auto;
}
.data-mono{
  font-family:var(--font-mono);
  font-size:13.5px;
  letter-spacing:.02em;
  font-variant-numeric:tabular-nums;
  white-space:nowrap;
}

/* ---------- 5. 按钮 / 胶囊 / 复制 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.55em;
  padding:.72em 1.25em;
  background:transparent;
  border:var(--bw) solid var(--gold);
  color:var(--gold);
  font-family:var(--font-title);
  font-size:14px;
  letter-spacing:.04em;
  text-decoration:none;
  box-shadow:6px 6px 0 var(--line);
  cursor:pointer;
  transition:background var(--t-press) linear,color var(--t-press) linear,box-shadow var(--t-press) linear,border-color var(--t-press) linear;
}
.btn:hover{
  background:var(--gold);
  color:var(--ink);
  box-shadow:6px 6px 0 var(--gold-deep);
}
.btn--primary{
  background:var(--violet);
  border-color:var(--violet);
  color:#F6F3EC;
  box-shadow:6px 6px 0 var(--line);
}
.btn--primary:hover{
  background:#9066FF;
  border-color:#9066FF;
  color:#F6F3EC;
  box-shadow:6px 6px 0 var(--gold-deep);
}
.btn--ghost{
  border-color:var(--gold-deep);
  color:var(--muted);
}
.btn--ghost:hover{
  background:transparent;
  border-color:var(--gold);
  color:var(--gold-hi);
  box-shadow:6px 6px 0 var(--line);
}
.pill-field{display:flex;flex-wrap:wrap;gap:8px}
.pill{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:6px 12px;
  background:transparent;
  border:1px solid var(--gold-deep);
  color:var(--muted);
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.04em;
  text-decoration:none;
  cursor:pointer;
  transition:color var(--t-press) linear,border-color var(--t-press) linear,background var(--t-press) linear;
}
.pill:hover{color:var(--gold-hi);border-color:var(--gold)}
.pill[aria-pressed="true"],
.pill[data-checked="true"]{
  background:var(--gold);
  border-color:var(--gold);
  color:var(--ink);
  box-shadow:4px 4px 0 var(--gold-deep);
}
.copy-btn{
  display:inline-flex;
  align-items:center;
  padding:3px 10px;
  background:transparent;
  border:1px solid var(--gold-deep);
  color:var(--gold);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  cursor:pointer;
  transition:border-color var(--t-press) linear,background var(--t-press) linear,color var(--t-press) linear;
}
.copy-btn:hover{border-color:var(--gold);color:var(--gold-hi);box-shadow:3px 3px 0 var(--gold-deep)}
.copy-btn[data-state="done"]{background:var(--cyan);border-color:var(--cyan);color:var(--ink)}

/* ---------- 6. 状态 / 数据面板 ---------- */
.dot{
  display:inline-block;
  width:9px;
  height:9px;
  border-radius:50%;
  background:var(--gold-deep);
  flex:0 0 auto;
}
.dot--gold{background:var(--gold)}
.dot--cyan{background:var(--cyan)}
.dot--ruby{background:var(--ruby)}
.dot--dim{background:var(--line);border:1px solid var(--gold-deep)}
.dot--pulse{animation:dot-pulse 2.4s ease-in-out infinite}
@keyframes dot-pulse{0%,100%{opacity:1}50%{opacity:.34}}

.status-panel{
  background:var(--panel);
  border:var(--bw) solid var(--line);
  box-shadow:var(--shadow-gold);
}
.status-panel__head{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding:12px 16px;
  border-bottom:1px solid var(--line);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--muted);
}
.status-panel__body{padding:4px 16px 12px}
.status-panel__row{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding:11px 0;
  border-bottom:1px dashed var(--line);
}
.status-panel__row:last-child{border-bottom:0}
.status-panel__label{display:flex;align-items:center;gap:8px;font-size:14.5px;color:var(--paper)}
.status-panel__value{
  font-family:var(--font-mono);
  font-size:14px;
  color:var(--gold);
  white-space:nowrap;
}
.status-panel__value[data-state="ok"]{color:var(--cyan)}
.status-panel__value[data-state="error"]{color:var(--ruby)}
.status-panel__value[data-state="idle"]{color:var(--gold-deep)}

/* ---------- 7. 卡片 / 滚轮 / 步骤 / 索引 / 关系图 ---------- */
.card{
  background:var(--panel);
  border:var(--bw) solid var(--line);
  padding:clamp(18px,2.4vw,28px);
  box-shadow:var(--shadow-hard);
}
.card--gold{border-color:var(--gold-deep)}
.card__meta{
  display:flex;
  flex-wrap:wrap;
  gap:6px 14px;
  margin-top:14px;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.04em;
  color:var(--muted);
}

.reel{
  position:relative;
  background:var(--panel-2);
  border:var(--bw) solid var(--gold-deep);
  box-shadow:var(--shadow-hard);
  overflow:hidden;
}
.reel__cell{
  padding:clamp(14px,2vw,22px);
  border-bottom:1px dashed var(--line);
}
.reel__cell:last-child{border-bottom:0}
.reel__line{
  position:absolute;
  left:0;right:0;
  top:50%;
  height:3px;
  background:var(--gold);
  opacity:.32;
  pointer-events:none;
}

.step-chain{list-style:none;margin:0;padding:0}
.step-chain__item{
  position:relative;
  padding:18px 0 18px 58px;
  border-bottom:1px dashed var(--gold-deep);
}
.step-chain__item:last-child{border-bottom:0}
.step-chain__num{
  position:absolute;
  left:0;top:18px;
  width:38px;height:38px;
  display:flex;align-items:center;justify-content:center;
  background:var(--panel);
  border:var(--bw) solid var(--gold-deep);
  font-family:var(--font-mono);
  font-size:14px;
  color:var(--gold);
}
.step-chain__item[data-done="true"] .step-chain__num{
  background:var(--cyan);
  border-color:var(--cyan);
  color:var(--ink);
}
.step-chain__title{font-size:17px;margin:0 0 4px}
.step-chain__text{margin:0;color:var(--muted);font-size:15px}

.index-list{list-style:none;margin:0;padding:0;counter-reset:idx}
.index-list__item{
  display:grid;
  grid-template-columns:52px minmax(0,1fr) auto;
  gap:12px;
  align-items:baseline;
  padding:14px 0;
  border-bottom:1px solid var(--line);
}
.index-list__item::before{
  counter-increment:idx;
  content:counter(idx,decimal-leading-zero);
  font-family:var(--font-mono);
  font-size:13px;
  color:var(--gold-deep);
}
.index-list__link{
  color:var(--paper);
  text-decoration:none;
  border-bottom:1px solid transparent;
}
.index-list__link:hover{color:var(--gold-hi);border-bottom-color:var(--cyan)}

.node-map{
  background:var(--panel);
  border:var(--bw) solid var(--line);
  padding:16px;
}
.node-map svg{display:block;width:100%;height:auto}
.node-map__line{stroke:var(--gold-deep);stroke-width:1;fill:none}
.node-map__line--cyan{stroke:var(--cyan)}
.node-map__node{fill:var(--panel-2);stroke:var(--gold);stroke-width:1.5}

/* ---------- 8. 折叠组 ---------- */
.accordion{
  background:var(--panel);
  border:var(--bw) solid var(--line);
  box-shadow:var(--shadow-hard);
  margin-bottom:12px;
}
.accordion__summary{
  display:flex;
  align-items:center;
  gap:12px;
  padding:16px 18px;
  cursor:pointer;
  list-style:none;
  font-family:var(--font-title);
  font-size:16px;
  color:var(--paper);
}
.accordion__summary::-webkit-details-marker{display:none}
.accordion__summary::before{
  content:"+";
  width:18px;
  text-align:center;
  font-family:var(--font-mono);
  font-size:18px;
  color:var(--gold);
}
.accordion[open] > .accordion__summary{background:var(--panel-2);color:var(--gold)}
.accordion[open] > .accordion__summary::before{content:"–"}
.accordion__body{
  padding:0 18px 18px;
  border-top:1px dashed var(--line);
  color:var(--muted);
  font-size:15.5px;
}
.accordion__body > :first-child{margin-top:14px}
.accordion[open] > .accordion__body{animation:acc-in var(--t-expand) ease-out}
@keyframes acc-in{from{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:none}}

/* ---------- 9. 锚点目录 / 面包屑 / 正文 ---------- */
.anchor-nav{
  position:sticky;
  top:112px;
  border-left:var(--bw) solid var(--line);
  padding-left:14px;
}
.anchor-nav__title{
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.18em;
  color:var(--gold-deep);
  margin:0;
}
.anchor-nav__list{list-style:none;margin:12px 0 0;padding:0}
.anchor-nav__link{
  display:block;
  padding:7px 0;
  color:var(--muted);
  text-decoration:none;
  font-size:14px;
  transition:color var(--t-press) linear,box-shadow var(--t-press) linear;
}
.anchor-nav__link:hover{color:var(--gold-hi)}
.anchor-nav__link[aria-current="true"]{
  color:var(--gold);
  box-shadow:inset 3px 0 0 var(--violet);
  padding-left:10px;
}

.breadcrumb{padding-block:16px;border-bottom:1px solid var(--line)}
.breadcrumb__list{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  list-style:none;
  font-family:var(--font-mono);
  font-size:12.5px;
  color:var(--muted);
}
.breadcrumb__item + .breadcrumb__item::before{content:"/";margin-right:8px;color:var(--gold-deep)}
.breadcrumb__link{color:var(--muted);text-decoration:none;border-bottom:1px solid var(--cyan)}
.breadcrumb__link:hover{color:var(--gold)}
.breadcrumb__current{color:var(--gold)}

.prose{max-width:68ch}
.prose p{margin:0 0 1.1em}
.prose h2{font-size:clamp(22px,3vw,32px);margin:1.8em 0 .6em}
.prose h3{font-size:clamp(18px,2.2vw,23px);margin:1.6em 0 .5em}
.prose ul,.prose ol{padding-left:1.3em;margin:0 0 1.1em}
.prose li{margin-bottom:.45em}
.prose a{color:var(--gold);text-decoration:none;border-bottom:1px solid var(--cyan)}
.prose a:hover{color:var(--gold-hi)}
.prose strong{color:var(--gold-hi)}
.prose code{
  font-family:var(--font-mono);
  font-size:.92em;
  color:var(--gold);
  border:1px solid var(--line);
  padding:1px 6px;
}

/* ---------- 10. 图片容器 ---------- */
.img-frame{
  position:relative;
  display:block;
  overflow:hidden;
  background:var(--panel);
  border:var(--bw) solid var(--line);
  box-shadow:var(--shadow-hard);
}
.img-frame > img,
.img-frame > picture > img,
.img-frame > svg{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
}
.img-frame--wide{aspect-ratio:16/9}
.img-frame--tall{aspect-ratio:3/4}
.img-frame--square{aspect-ratio:1/1}
.img-frame--hero{aspect-ratio:21/9}
.img-frame--slant{
  clip-path:polygon(0 0,100% 0,100% 84%,0 100%);
  border-bottom:0;
}
.img-frame__caption{
  margin-top:10px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--muted);
}

/* ---------- 11. 显现 ---------- */
[data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity 420ms ease-out,transform 420ms ease-out;
}
[data-reveal].is-visible{opacity:1;transform:none}

/* ---------- 12. skip link ---------- */
.skip-link{
  position:absolute;
  left:12px;
  top:-120px;
  z-index:120;
  background:var(--gold);
  color:var(--ink);
  border:var(--bw) solid var(--ink);
  padding:10px 16px;
  font-family:var(--font-title);
  font-size:14px;
  text-decoration:none;
  transition:top var(--t-press) ease-out;
}
.skip-link:focus{top:8px}

/* ---------- 13. 头部 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:60;
  background:rgba(7,7,11,.95);
  backdrop-filter:blur(6px);
  border-bottom:var(--bw) solid var(--line);
}
.tier-one{
  background:var(--panel-2);
  border-bottom:1px solid var(--line);
}
.tier-one__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  min-height:34px;
}
.tier-one__brand{
  margin:0;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.12em;
  color:var(--gold);
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}
.tier-one__meta{
  display:flex;
  align-items:center;
  gap:20px;
  list-style:none;
  flex:0 0 auto;
}
.tier-one__item{
  display:flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--muted);
  white-space:nowrap;
}
.tier-one__item--lang{color:var(--cyan)}
.tier-one__item--icp{color:var(--gold-deep)}

.tier-two{position:relative}
.tier-two__inner{
  display:flex;
  align-items:center;
  gap:clamp(12px,2vw,26px);
  padding-block:10px;
  min-height:66px;
}
.brand{
  display:flex;
  align-items:center;
  gap:12px;
  flex:0 0 auto;
  text-decoration:none;
}
.brand__mark{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-width:66px;
  padding:6px 10px;
  background:var(--gold);
  color:var(--ink);
  font-family:var(--font-display);
  font-weight:600;
  font-size:24px;
  line-height:1;
  letter-spacing:-.04em;
  box-shadow:5px 5px 0 var(--violet);
}
.brand__text{display:flex;flex-direction:column;line-height:1.2}
.brand__name{font-family:var(--font-title);font-size:18px;letter-spacing:.02em;color:var(--paper)}
.brand__line{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:var(--muted);
}

.site-nav{
  display:flex;
  align-items:center;
  gap:clamp(10px,1.6vw,22px);
  margin-left:auto;
}
.site-nav__list{
  display:flex;
  align-items:center;
  gap:clamp(6px,1.2vw,18px);
  list-style:none;
  overflow-x:auto;
  scrollbar-width:none;
}
.site-nav__list::-webkit-scrollbar{display:none}
.site-nav__item{list-style:none;flex:0 0 auto}
.site-nav__link{
  position:relative;
  display:inline-block;
  padding:10px 2px;
  color:var(--paper);
  font-size:14.5px;
  letter-spacing:.02em;
  text-decoration:none;
  white-space:nowrap;
  border-bottom:3px solid transparent;
  transition:color var(--t-press) linear,border-color var(--t-press) linear;
}
.site-nav__link:hover{color:var(--gold-hi)}
.site-nav__link[aria-current="page"]{
  color:var(--gold);
  border-bottom-color:var(--gold);
}
.site-nav__link[aria-current="page"]::after{
  content:"";
  position:absolute;
  left:0;right:0;
  bottom:-7px;
  height:3px;
  background:var(--violet);
}
.site-nav__cta{flex:0 0 auto;font-size:13.5px;padding:.62em 1.1em}

.nav-toggle{
  display:none;
  align-items:center;
  gap:10px;
  margin-left:auto;
  padding:9px 12px;
  background:var(--panel);
  border:1px solid var(--gold-deep);
  color:var(--gold);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  cursor:pointer;
  transition:background var(--t-press) linear,color var(--t-press) linear,border-color var(--t-press) linear;
}
.nav-toggle__bars{
  position:relative;
  display:block;
  width:18px;
  height:2px;
  background:var(--gold);
}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;
  width:18px;
  height:2px;
  background:var(--gold);
}
.nav-toggle__bars::before{top:-6px}
.nav-toggle__bars::after{top:6px}
.nav-toggle[aria-expanded="true"]{background:var(--gold);border-color:var(--gold);color:var(--ink)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars,
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before,
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{background:var(--ink)}

.scroll-progress{
  position:absolute;
  left:0;bottom:0;
  width:100%;
  height:3px;
  background:var(--gold);
  transform:scaleX(0);
  transform-origin:0 50%;
  z-index:2;
}

/* ---------- 14. 页脚 ---------- */
.site-footer{
  margin-top:var(--sec);
  background:var(--panel-2);
  border-top:var(--bw) solid var(--line);
}
.footer__status{
  background:var(--ink);
  border-bottom:1px solid var(--line);
}
.footer__status-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  min-height:44px;
}
.footer__status-line{
  display:flex;
  align-items:center;
  gap:10px;
  margin:0;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.1em;
  color:var(--gold);
}
.footer__status-code{
  margin:0;
  color:var(--gold-deep);
  letter-spacing:.14em;
}
.footer__main{
  display:grid;
  grid-template-columns:minmax(260px,1fr) minmax(0,1.7fr);
  gap:clamp(24px,4vw,64px);
  padding-block:clamp(36px,5vw,64px);
}
.footer__mark{
  margin:0;
  font-family:var(--font-display);
  font-weight:200;
  font-size:clamp(48px,7vw,72px);
  line-height:.86;
  letter-spacing:-.04em;
  color:var(--gold-deep);
}
.footer__name{
  margin:6px 0 0;
  font-family:var(--font-title);
  font-size:19px;
  color:var(--paper);
}
.footer__line{
  margin:4px 0 0;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.12em;
  color:var(--muted);
}
.footer__contact{
  list-style:none;
  display:grid;
  gap:10px;
  margin:22px 0 0;
}
.footer__contact-item{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
  font-size:14px;
}
.footer__contact-label{
  min-width:36px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  color:var(--gold-deep);
}
.footer__contact-value{
  color:var(--paper);
  white-space:normal;
  word-break:break-all;
}
.footer__note{
  margin:16px 0 0;
  padding-left:14px;
  border-left:var(--bw) solid var(--line);
  color:var(--muted);
  font-size:13.5px;
  line-height:1.7;
  max-width:46ch;
}
.footer__cols{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:clamp(18px,3vw,40px);
}
.footer__col-title{
  font-size:13px;
  letter-spacing:.18em;
  color:var(--gold);
  margin:0 0 14px;
  padding-bottom:10px;
  border-bottom:1px solid var(--line);
}
.footer__list{list-style:none}
.footer__link{
  display:inline-block;
  padding:5px 0;
  color:var(--muted);
  font-size:14px;
  text-decoration:none;
  transition:color var(--t-press) linear,padding-left var(--t-press) linear;
}
.footer__link:hover{color:var(--gold);padding-left:6px}
.footer__legal{
  background:var(--ink);
  border-top:1px solid var(--line);
}
.footer__legal-inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px 28px;
  min-height:56px;
  padding-block:12px;
}
.footer__legal-item{margin:0;color:var(--muted);font-size:12.5px;letter-spacing:.06em}

.to-top{
  position:fixed;
  right:clamp(12px,2vw,28px);
  bottom:clamp(12px,2vw,28px);
  z-index:70;
  padding:10px 14px;
  background:var(--panel);
  border:var(--bw) solid var(--gold-deep);
  color:var(--gold);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  cursor:pointer;
  opacity:0;
  visibility:hidden;
  transform:translateY(8px);
  transition:opacity var(--t-collapse) linear,transform var(--t-collapse) ease-out,visibility var(--t-collapse) linear;
}
.to-top[data-visible="true"]{opacity:1;visibility:visible;transform:none}
.to-top:hover{border-color:var(--gold);color:var(--gold-hi);box-shadow:5px 5px 0 var(--gold-deep)}

/* ---------- 15. 响应式 ---------- */
@media (max-width:1080px){
  .footer__main{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:900px){
  .tier-one__meta{display:none}
  .tier-one__inner{justify-content:flex-start}
  .brand__line{display:none}
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:absolute;
    top:100%;
    left:0;right:0;
    z-index:65;
    display:none;
    flex-direction:column;
    align-items:stretch;
    gap:0;
    margin-left:0;
    padding:6px 0 16px;
    background:var(--panel);
    border-top:var(--bw) solid var(--gold);
    border-bottom:var(--bw) solid var(--line);
    box-shadow:0 10px 0 rgba(0,0,0,.55);
  }
  .site-nav[data-open]{display:block}
  .site-nav__list{
    flex-direction:column;
    align-items:stretch;
    gap:0;
    overflow:visible;
    padding-inline:var(--gutter);
  }
  .site-nav__item{width:100%}
  .site-nav__link{
    display:block;
    width:100%;
    padding:13px 0;
    font-size:17px;
    border-bottom:1px solid var(--line);
  }
  .site-nav__link[aria-current="page"]{
    border-bottom-color:var(--gold);
    padding-left:12px;
  }
  .site-nav__link[aria-current="page"]::after{
    left:0;
    right:auto;
    width:4px;
    top:0;
    bottom:0;
    height:auto;
  }
  .site-nav__cta{
    margin:16px var(--gutter) 0;
    justify-content:center;
  }
  .grid--2,.grid--3{grid-template-columns:minmax(0,1fr)}
  .grid--12{grid-template-columns:repeat(6,minmax(0,1fr))}
  .anchor-nav{position:static;border-left:0;border-top:var(--bw) solid var(--line);padding:14px 0 0}
  .footer__cols{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:640px){
  body{font-size:15.5px}
  .btn{width:100%}
  .site-nav__cta{width:auto}
  .footer__cols{grid-template-columns:minmax(0,1fr)}
  .footer__legal-inner{gap:6px 18px}
  .index-list__item{grid-template-columns:44px minmax(0,1fr)}
  .grid--12{grid-template-columns:repeat(2,minmax(0,1fr))}
  .to-top{right:12px;bottom:12px}
}

/* ---------- 16. 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;
  }
  [data-reveal]{opacity:1;transform:none}
  .scroll-progress{transition:none}
}