/* =========================================================
   皇冠中文站 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 页头 / 页脚 / 基础组件
   ========================================================= */

/* ---------- 01 重置 ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;background:#0B0B0B}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd,fieldset{margin:0;padding:0}
ul,ol{list-style:none}
img,svg,video{display:block;max-width:100%}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
a{color:inherit;text-decoration:none}
[hidden]{display:none !important}

/* ---------- 02 设计令牌 ---------- */
:root{
  --ink:#0B0B0B;
  --graphite:#2E2E2E;
  --gold:#C9A227;
  --gold-lift:#E6C86A;
  --gold-deep:#7A611A;
  --red:#6B1F2A;
  --paper:#F5F1E6;
  --white:#FFFFFF;
  --ash:#8A8A8A;
  --halo:#F0E2B6;
  --rule:#3A3A3A;

  --font-head:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","Source Han Mono","SFMono-Regular",Consolas,monospace;

  --fs-12:12px;--fs-14:14px;--fs-17:17px;--fs-20:20px;
  --fs-28:28px;--fs-40:40px;--fs-56:56px;--fs-84:84px;

  --sp-1:8px;--sp-2:16px;--sp-3:24px;--sp-4:32px;--sp-6:48px;--sp-8:64px;--sp-12:96px;

  --rail-w:0px;
  --header-h:68px;
  --maxw:1440px;
}
@media (min-width:1024px){
  :root{--rail-w:88px;--header-h:76px}
}

/* ---------- 03 基底与中文排版 ---------- */
body{
  min-height:100vh;
  background-color:var(--ink);
  background-image:
    radial-gradient(58% 42% at 80% 2%, rgba(201,162,39,.10), transparent 70%),
    radial-gradient(46% 38% at 0% 96%, rgba(107,31,42,.13), transparent 72%);
  background-attachment:fixed;
  background-repeat:no-repeat;
  color:var(--paper);
  font-family:var(--font-body);
  font-size:var(--fs-17);
  font-weight:400;
  line-height:1.9;
  padding-inline-start:var(--rail-w);
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4{font-family:var(--font-head);font-weight:900;line-height:1.15;letter-spacing:-.01em;color:var(--white);text-align:left}
h1{font-size:clamp(40px,6vw,84px)}
h2{font-size:clamp(24px,3vw,40px)}
h3{font-size:var(--fs-20);font-weight:700;line-height:1.4;color:var(--paper)}
h4{font-size:var(--fs-17);font-weight:700;line-height:1.5;color:var(--paper)}
p{text-wrap:pretty}
strong,b{font-weight:500;color:var(--white)}
::selection{background:var(--gold);color:var(--ink)}

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

.mono{font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;text-transform:uppercase}

/* ---------- 04 版心与栅格 ---------- */
.shell{width:100%;max-width:var(--maxw);margin-inline:auto;padding-inline:24px}
@media (min-width:1024px){.shell{padding-inline:40px}}

.grid{display:grid;gap:var(--sp-3);grid-template-columns:repeat(4,minmax(0,1fr))}
@media (min-width:768px){.grid{grid-template-columns:repeat(8,minmax(0,1fr))}}
@media (min-width:1024px){.grid{grid-template-columns:repeat(12,minmax(0,1fr));gap:var(--sp-3)}}
.span-3,.span-4,.span-6,.span-8,.span-9,.span-12{grid-column:1/-1}
@media (min-width:768px){
  .span-3,.span-4{grid-column:span 4}
  .span-6,.span-8,.span-9,.span-12{grid-column:span 8}
}
@media (min-width:1024px){
  .span-3{grid-column:span 3}
  .span-4{grid-column:span 4}
  .span-6{grid-column:span 6}
  .span-8{grid-column:span 8}
  .span-9{grid-column:span 9}
  .span-12{grid-column:span 12}
}

#main-content{display:block;padding-block-start:var(--header-h)}
.section{padding-block:var(--sp-8)}
@media (min-width:1024px){.section{padding-block:var(--sp-12)}}
.section + .section{border-top:1px solid rgba(58,58,58,.55)}

.section-head{max-width:52em;margin-block-end:var(--sp-6)}
.section-num{display:block;font-family:var(--font-mono);font-size:clamp(28px,4vw,40px);line-height:1;letter-spacing:.06em;color:var(--gold);margin-block-end:12px}
.section-title{font-family:var(--font-head);font-weight:900;font-size:clamp(24px,3vw,40px);line-height:1.2;color:var(--white)}
.section-title::after{content:"";display:block;width:56px;height:2px;background:var(--gold);margin-block-start:20px}
.section-lead{margin-block-start:var(--sp-2);color:var(--ash);max-width:36em;font-size:var(--fs-17)}

.page-head{padding-block:var(--sp-8) var(--sp-6);border-bottom:1px solid rgba(58,58,58,.55)}

.eyebrow{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.16em;text-transform:uppercase;color:var(--gold)}
.eyebrow::before{content:"";width:28px;height:1px;background:var(--gold-deep)}

/* ---------- 05 正文容器 ---------- */
.prose{max-width:36em;font-size:var(--fs-17);line-height:1.9;color:var(--paper)}
.prose > * + *{margin-block-start:1.4em}
.prose h2,.prose h3{margin-block-start:2em}
.prose ul,.prose ol{max-width:36em}
.prose li{position:relative;padding-inline-start:1.5em;margin-block-start:.5em}
.prose li::before{content:"";position:absolute;inset-inline-start:0;top:.95em;width:10px;height:1px;background:var(--gold)}
.prose a{border-bottom:1px solid var(--gold-deep);color:var(--gold-lift)}

/* ---------- 06 通用按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.1em;text-transform:uppercase;
  padding:14px 22px;border:1px solid var(--gold);color:var(--gold);background:transparent;
  transition:background .2s ease-out,color .2s ease-out,border-color .2s ease-out,transform .12s ease-out;
}
.btn:hover{background:var(--gold);color:var(--ink)}
.btn:active{transform:translateY(1px)}
.btn--solid{background:var(--gold);color:var(--ink)}
.btn--solid:hover{background:var(--gold-lift);border-color:var(--gold-lift);color:var(--ink)}
.btn--ghost{border-color:var(--rule);color:var(--ash)}
.btn--ghost:hover{border-color:var(--gold);color:var(--gold);background:transparent}
.btn[disabled],.btn[aria-disabled="true"]{opacity:.45;pointer-events:none}

/* ---------- 07 卡片 / 研究板 / 标签 ---------- */
.card{
  position:relative;background:var(--graphite);border:1px solid var(--rule);
  padding:var(--sp-4) var(--sp-3);
  transition:border-color .22s ease-out,transform .22s ease-out;
}
.card::before{content:"";position:absolute;top:-1px;left:0;width:44px;height:1px;background:var(--gold);transition:width .28s ease-out}
.card:hover{border-color:var(--gold-deep);transform:translateY(-2px)}
.card:hover::before{width:100%}
.card__kicker{display:block;font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.12em;color:var(--ash);text-transform:uppercase}
.card__title{font-family:var(--font-head);font-weight:900;font-size:var(--fs-20);line-height:1.35;color:var(--white);margin-block-start:12px}
.card__text{margin-block-start:12px;color:var(--ash);font-size:var(--fs-17);max-width:32em}
.card__link{display:inline-flex;align-items:center;gap:8px;margin-block-start:20px;font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.1em;color:var(--gold);border-bottom:1px solid transparent;transition:border-color .2s ease-out,color .2s ease-out}
.card__link::after{content:"→"}
.card__link:hover{color:var(--gold-lift);border-bottom-color:var(--gold-lift)}

.board{border:1px solid var(--rule);background:linear-gradient(180deg,rgba(46,46,46,.92),rgba(11,11,11,.92))}
.board__label{display:block;font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.16em;text-transform:uppercase;color:var(--gold);padding:14px 20px;border-bottom:1px solid var(--rule)}
.board__row{display:grid;grid-template-columns:88px 1fr;gap:16px;padding:16px 20px;border-bottom:1px solid rgba(58,58,58,.7)}
.board__row:last-child{border-bottom:0}
.board__key{font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;color:var(--ash)}
.board__val{color:var(--paper);font-size:15px;line-height:1.8}
@media (min-width:768px){.board__row{grid-template-columns:120px 1fr}}

.tag{display:inline-block;font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;color:var(--gold-lift);border:1px solid var(--gold-deep);padding:3px 8px}
.stamp{display:inline-block;background:var(--red);color:var(--paper);font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;padding:4px 10px}

.note{border-left:2px solid var(--gold);background:rgba(46,46,46,.6);padding:16px 20px;font-size:15px;line-height:1.8;color:var(--paper)}
.note--alert{border-left-color:var(--red)}

/* ---------- 08 面包屑 ---------- */
.crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:10px;font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;color:var(--ash)}
.crumbs a{color:var(--ash);transition:color .2s ease-out}
.crumbs a:hover{color:var(--gold-lift)}
.crumbs__sep{color:var(--gold-deep)}

/* ---------- 09 图形容器（响应式占位） ---------- */
.figure{margin:0}
.figure__frame{
  position:relative;display:block;overflow:hidden;
  border:1px solid var(--rule);
  aspect-ratio:16/9;
  background:
    radial-gradient(120% 90% at 22% 8%, rgba(240,226,182,.16), transparent 62%),
    linear-gradient(180deg,var(--graphite),var(--ink));
}
.figure__frame > img,.figure__frame > svg{width:100%;height:100%;object-fit:cover;display:block}
.figure__frame--wide{aspect-ratio:21/9}
.figure__frame--tall{aspect-ratio:4/5}
.figure__cap{margin-block-start:10px;font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;color:var(--ash)}
.gridlines{
  position:absolute;inset:0;pointer-events:none;
  background-image:
    linear-gradient(to right, rgba(58,58,58,.55) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(58,58,58,.55) 1px, transparent 1px);
  background-size:64px 64px;
  -webkit-mask-image:linear-gradient(180deg,rgba(0,0,0,.9),transparent 88%);
  mask-image:linear-gradient(180deg,rgba(0,0,0,.9),transparent 88%);
}

/* ---------- 10 跳转链接 ---------- */
.skip-link{
  position:fixed;top:8px;left:8px;z-index:200;
  transform:translateY(-180%);
  background:var(--gold);color:var(--ink);
  font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;
  padding:10px 16px;
  transition:transform .2s ease-out;
}
.skip-link:focus{transform:none}

/* ---------- 11 页头 ---------- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:60;
  background:rgba(11,11,11,.86);
  border-bottom:1px solid transparent;
  transition:background .3s ease-out,border-color .3s ease-out;
}
.site-header[data-condensed="true"]{background:rgba(11,11,11,.96);border-bottom-color:var(--rule)}

.progress-rail{position:absolute;top:0;left:0;right:0;height:2px;background:rgba(58,58,58,.5)}
.progress-bar{display:block;height:100%;width:100%;background:linear-gradient(90deg,var(--gold-deep),var(--gold),var(--gold-lift));transform:scaleX(0);transform-origin:0 50%}

.header-inner{
  display:flex;align-items:center;justify-content:space-between;gap:var(--sp-3);
  min-height:var(--header-h);
  padding:10px 20px;
}
@media (min-width:1024px){
  .header-inner{padding-inline-start:calc(var(--rail-w) + 24px);padding-inline-end:40px}
}

.brand{display:inline-flex;align-items:center;gap:12px;min-width:0}
.brand-mark{display:block;width:26px;height:23px;flex:none;color:var(--gold)}
.brand-mark svg{width:100%;height:100%;display:block}
.brand-text{display:flex;flex-direction:column;line-height:1.2;min-width:0}
.brand-name{font-family:var(--font-head);font-weight:700;font-size:var(--fs-17);color:var(--white);letter-spacing:.02em;white-space:nowrap}
.brand-sub{font-family:var(--font-mono);font-size:10px;letter-spacing:.16em;color:var(--ash);text-transform:uppercase;white-space:nowrap}
.brand:hover .brand-name{color:var(--gold-lift)}

.nav-toggle{
  position:relative;z-index:80;
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.16em;text-transform:uppercase;
  color:var(--paper);border:1px solid var(--rule);padding:9px 12px;
  transition:border-color .2s ease-out,color .2s ease-out;
}
.nav-toggle:hover{border-color:var(--gold);color:var(--gold)}
.nav-toggle-bar{display:block;width:16px;height:1px;background:currentColor;box-shadow:0 5px 0 currentColor,0 -5px 0 currentColor}
.nav-toggle[aria-expanded="true"]{border-color:var(--gold);color:var(--gold)}
@media (min-width:1024px){.nav-toggle{display:none}}

.site-nav{position:relative}
.nav-list{display:flex;align-items:center;gap:0}
.nav-link{
  position:relative;display:inline-flex;align-items:baseline;gap:8px;
  padding:10px 14px;
  font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;
  color:var(--ash);
  transition:color .2s ease-out;
}
.nav-num{font-size:11px;color:var(--gold-deep);letter-spacing:.06em}
.nav-label{white-space:nowrap}
.nav-link::after{
  content:"";position:absolute;left:14px;right:14px;bottom:4px;height:1px;background:var(--gold-lift);
  transform:scaleX(0);transform-origin:0 50%;
  transition:transform .22s ease-out;
}
.nav-link:hover{color:var(--paper)}
.nav-link:hover::after,.nav-link:focus-visible::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--gold)}
.nav-link[aria-current="page"] .nav-num{color:var(--gold-lift)}
.nav-link[aria-current="page"]::after{transform:scaleX(1);background:var(--gold)}

/* 桌面：滚动后索引滑入左侧轨道 */
@media (min-width:1024px){
  .site-header[data-condensed="true"] .site-nav{
    position:fixed;left:0;top:50%;transform:translateY(-50%);
    width:var(--rail-w);
    padding:var(--sp-2) 0;
    background:linear-gradient(90deg,rgba(11,11,11,.97),rgba(11,11,11,.74));
    border-right:1px solid var(--rule);
    animation:railDrop .34s ease-out both;
  }
  .site-header[data-condensed="true"] .nav-list{flex-direction:column;align-items:flex-start;gap:2px}
  .site-header[data-condensed="true"] .nav-link{width:100%;padding:9px 0 9px 18px;font-size:11px}
  .site-header[data-condensed="true"] .nav-link::after{left:18px;right:18px;bottom:2px}
  .site-header[data-condensed="true"] .nav-label{
    position:absolute;left:calc(100% + 8px);top:50%;
    transform:translateY(-50%) translateX(-6px);
    opacity:0;pointer-events:none;
    padding:4px 10px;background:var(--ink);border:1px solid var(--rule);
    color:var(--paper);font-size:11px;letter-spacing:.06em;
    transition:opacity .18s ease-out,transform .18s ease-out;
  }
  .site-header[data-condensed="true"] .nav-link:hover .nav-label,
  .site-header[data-condensed="true"] .nav-link:focus-visible .nav-label{opacity:1;transform:translateY(-50%)}
}
@keyframes railDrop{
  from{opacity:0;transform:translateY(-50%) translateX(-14px)}
  to{opacity:1;transform:translateY(-50%) translateX(0)}
}

/* 移动端：全屏索引面板 */
@media (max-width:1023px){
  .site-nav{
    position:fixed;inset:0;z-index:70;
    display:flex;align-items:center;justify-content:center;
    padding:calc(var(--header-h) + 24px) 24px 48px;
    background:radial-gradient(70% 45% at 72% 6%, rgba(201,162,39,.12), transparent 70%), var(--ink);
    opacity:0;visibility:hidden;transform:translateY(-10px);
    transition:opacity .24s ease-out,transform .24s ease-out,visibility 0s linear .24s;
  }
  .site-nav[data-open="true"]{opacity:1;visibility:visible;transform:none;transition-delay:0s,0s,0s}
  .nav-list{flex-direction:column;align-items:stretch;gap:0;width:100%;max-width:440px}
  .nav-item{border-bottom:1px solid rgba(58,58,58,.75)}
  .nav-item:first-child{border-top:1px solid rgba(58,58,58,.75)}
  .nav-link{width:100%;padding:18px 6px;font-size:var(--fs-14);letter-spacing:.1em;justify-content:flex-start}
  .nav-num{font-size:var(--fs-12);color:var(--gold-deep)}
  .nav-link::after{left:6px;right:6px;bottom:8px}
  .nav-link[aria-current="page"] .nav-num{color:var(--gold)}
}

/* ---------- 12 页脚 ---------- */
.site-footer{
  position:relative;
  margin-block-start:var(--sp-12);
  border-top:1px solid var(--rule);
  background:linear-gradient(180deg,rgba(46,46,46,.5),rgba(11,11,11,1) 42%);
  padding-block:var(--sp-12) var(--sp-3);
}
.footer-inner{width:100%;max-width:var(--maxw);margin-inline:auto;padding-inline:24px}
@media (min-width:1024px){.footer-inner{padding-inline:40px}}

.footer-grid{display:grid;gap:var(--sp-6);grid-template-columns:1fr}
@media (min-width:768px){.footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (min-width:1024px){.footer-grid{grid-template-columns:1.1fr .9fr 1.4fr;gap:var(--sp-8)}}

.footer-brand .brand-mark{width:34px;height:30px;margin-block-end:var(--sp-2)}
.footer-sign{font-family:var(--font-head);font-weight:700;font-size:var(--fs-20);color:var(--white);line-height:1.4}
.footer-greet{margin-block-start:6px;font-size:var(--fs-14);color:var(--ash);font-family:var(--font-mono);letter-spacing:.06em}

.footer-heading{
  font-family:var(--font-mono);font-size:var(--fs-12);font-weight:400;
  letter-spacing:.16em;text-transform:uppercase;color:var(--gold);
  line-height:1.5;margin-block-end:var(--sp-2);
}
.footer-list{display:flex;flex-direction:column;gap:2px}
.footer-list--sub{margin-block-start:var(--sp-2);padding-block-start:var(--sp-2);border-top:1px solid rgba(58,58,58,.65)}
.footer-item{line-height:1.6}
.footer-link{
  display:inline-block;padding-block:5px;
  font-size:var(--fs-14);color:var(--ash);
  border-bottom:1px solid transparent;
  transition:color .2s ease-out,border-color .2s ease-out;
}
.footer-link:hover{color:var(--gold-lift);border-bottom-color:var(--gold-deep)}

.contact-list{border-top:1px solid rgba(58,58,58,.65)}
.contact-item{display:flex;flex-wrap:wrap;align-items:center;gap:6px 12px;padding-block:12px;border-bottom:1px solid rgba(58,58,58,.65)}
.contact-key{font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;color:var(--ash);min-width:70px}
.contact-value{font-family:var(--font-mono);font-size:var(--fs-14);letter-spacing:.02em;color:var(--paper);word-break:break-all}
.contact-value--addr{font-family:var(--font-body);font-size:var(--fs-14);line-height:1.7}
.copy-btn{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  color:var(--gold);border:1px solid var(--gold-deep);padding:3px 8px;
  transition:background .2s ease-out,color .2s ease-out,border-color .2s ease-out;
}
.copy-btn:hover{background:var(--gold);color:var(--ink);border-color:var(--gold)}
.copy-btn[data-copied="true"]{background:var(--red);border-color:var(--red);color:var(--paper)}
.footer-note{margin-block-start:var(--sp-2);font-size:var(--fs-14);line-height:1.8;color:var(--ash);max-width:34em}

.footer-meta{
  display:flex;flex-wrap:wrap;align-items:center;gap:10px 24px;
  margin-block-start:var(--sp-8);
  padding-block-start:var(--sp-3);
  border-top:1px solid var(--rule);
  font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.06em;color:var(--ash);
}
.footer-legal{color:var(--gold-deep)}
.footer-copy{color:var(--ash)}
.to-top{
  margin-inline-start:auto;
  font-family:var(--font-mono);font-size:var(--fs-12);letter-spacing:.1em;text-transform:uppercase;
  color:var(--paper);border:1px solid var(--rule);padding:8px 14px;
  transition:border-color .2s ease-out,color .2s ease-out,background .2s ease-out;
}
.to-top:hover{border-color:var(--gold);color:var(--gold)}
.to-top:active{transform:translateY(1px)}

/* ---------- 13 显现动效 ---------- */
html.js [data-reveal]{
  opacity:0;transform:translateY(8px);
  transition:opacity .28s ease-out,transform .28s ease-out;
}
html.js [data-reveal].is-visible{opacity:1;transform:none}

/* ---------- 14 可访问性：减弱动效 ---------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  html.js [data-reveal]{opacity:1;transform:none}
  .site-header[data-condensed="true"] .site-nav{animation:none}
  .card:hover{transform:none}
}