/* =========================================================
   乐思赛场 · 共享外壳样式 /assets/site.css
   观察窗框架 + 展览画册式画布
   ========================================================= */

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,figure,blockquote,dl,dd{margin:0;padding:0}
ul,ol{list-style:none}
img,svg,video{display:block;max-width:100%;height:auto}
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%}

:root{
  --ink:#0B1726;
  --ink-soft:#14283D;
  --rust:#A6432B;
  --mint:#5FF2C2;
  --gold:#F2B84B;
  --paper:#F6F3EC;
  --mist:#B8C2CC;
  --stone:#62707D;
  --pale:#D8E6E2;

  --bg:var(--ink);
  --fg:var(--paper);
  --fg-dim:var(--mist);
  --line:rgba(246,243,236,.14);
  --accent:var(--mint);
  --mark:var(--rust);

  --rail-w:96px;
  --bar-h:46px;
  --pad:clamp(1.25rem,5vw,5rem);
  --gap:clamp(1.1rem,2.4vw,2rem);

  --font-sans:"Source Han Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono","SFMono-Regular",ui-monospace,"Cascadia Mono",Consolas,monospace;
  --ease:cubic-bezier(.2,.7,.25,1);
}

body{
  min-height:100vh;
  background:var(--ink);
  color:var(--paper);
  font-family:var(--font-sans);
  font-size:17px;
  line-height:1.8;
  padding-left:var(--rail-w);
  padding-top:var(--bar-h);
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}

:focus-visible{outline:2px solid var(--mint);outline-offset:3px;border-radius:1px}
::selection{background:var(--rust);color:var(--paper)}

.sr-only{
  position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);clip-path:inset(50%);white-space:nowrap;border:0;
}

/* ---------------- 排版基准 ---------------- */
h1{font-size:clamp(2.3rem,5.2vw,4.2rem);line-height:1.06;font-weight:800;letter-spacing:-.015em}
h2{font-size:clamp(1.6rem,3vw,2.6rem);line-height:1.16;font-weight:700;letter-spacing:-.01em}
h3{font-size:clamp(1.12rem,1.6vw,1.4rem);line-height:1.4;font-weight:700}
h4{font-size:14px;line-height:1.5;font-weight:700;letter-spacing:.06em}

.display{font-size:clamp(3rem,8vw,7rem);line-height:.95;font-weight:800;letter-spacing:-.025em}
.lede{font-size:clamp(1.02rem,1.5vw,1.2rem);line-height:1.85;color:var(--fg-dim);max-width:60ch}

.eyebrow{
  display:inline-flex;align-items:center;gap:.6rem;
  font-family:var(--font-mono);font-size:12px;font-weight:500;
  letter-spacing:.18em;text-transform:uppercase;color:var(--fg-dim);
}
.eyebrow::before{content:"";width:22px;height:2px;background:var(--rust);flex:none}

.rule{display:block;width:46px;height:3px;background:var(--rust);border:0}
.hairline{display:block;width:100%;height:1px;background:var(--line);border:0}

/* ---------------- 画布与容器 ---------------- */
.canvas{background:var(--bg);color:var(--fg)}
.canvas--ink{--bg:#0B1726;--fg:#F6F3EC;--fg-dim:#B8C2CC;--line:rgba(246,243,236,.14)}
.canvas--night{--bg:#14283D;--fg:#F6F3EC;--fg-dim:#B8C2CC;--line:rgba(246,243,236,.18)}
.canvas--paper{--bg:#F6F3EC;--fg:#0B1726;--fg-dim:#62707D;--line:rgba(11,23,38,.16)}
.canvas--mist{--bg:#D8E6E2;--fg:#0B1726;--fg-dim:#4B5A66;--line:rgba(11,23,38,.14)}

.section{padding-block:clamp(2.8rem,7vw,6.5rem);padding-inline:var(--pad)}
.section--tight{padding-block:clamp(1.8rem,4vw,3.2rem)}
.section--flush{padding-inline:0}

.wrap{width:100%;max-width:78rem;margin-inline:auto}
.wrap--narrow{max-width:68ch}

.section__head{display:flex;flex-direction:column;gap:.9rem;margin-bottom:clamp(1.5rem,3vw,2.6rem)}
.section__title{font-size:clamp(1.75rem,3vw,3rem);line-height:1.1;font-weight:800;letter-spacing:-.015em;max-width:26ch}
.section__note{max-width:54ch;color:var(--fg-dim);font-size:16px;line-height:1.8}

.grid{display:grid;gap:var(--gap)}
.grid--split{grid-template-columns:minmax(0,1.35fr) minmax(0,1fr)}
.grid--tiles{grid-template-columns:repeat(auto-fit,minmax(min(100%,17rem),1fr))}

/* 浅色画布上的可读性修正 */
.canvas--paper .prose a,.canvas--mist .prose a{color:#8C3520}
.canvas--paper .stat__value,.canvas--mist .stat__value{color:var(--rust)}
.canvas--paper .tag--mint,.canvas--mist .tag--mint{color:#1F7A5E;border-color:rgba(31,122,94,.45)}
.canvas--paper .crumb__link,.canvas--mist .crumb__link{color:#8C3520}

/* ---------------- 按钮与标签 ---------------- */
.btn{
  display:inline-flex;align-items:center;gap:.6rem;
  padding:.78rem 1.3rem;border-radius:2px;border:1px solid transparent;
  font-size:14px;font-weight:700;letter-spacing:.04em;line-height:1.3;
  transition:background-color .3s var(--ease),color .3s var(--ease),border-color .3s var(--ease);
}
.btn--mint{background:var(--mint);color:var(--ink)}
.btn--mint:hover{background:var(--paper)}
.btn--ghost{border-color:var(--line);color:var(--fg)}
.btn--ghost:hover{border-color:var(--mint);color:var(--mint)}
.btn--gold{background:var(--gold);color:var(--ink)}
.btn--gold:hover{background:var(--paper);color:var(--ink)}

.tag{
  display:inline-flex;align-items:center;gap:.4rem;
  padding:.2rem .55rem;border-radius:2px;border:1px solid var(--line);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--fg-dim);
}
.tag--mint{color:var(--mint);border-color:rgba(95,242,194,.45)}
.tag--gold{color:var(--gold);border-color:rgba(242,184,75,.45)}
.tag--rust{background:var(--rust);color:var(--paper);border-color:transparent}

/* ---------------- 数据 ---------------- */
.stat{display:flex;flex-direction:column;gap:.25rem}
.stat__value{
  font-family:var(--font-mono);font-size:clamp(1.8rem,4vw,3rem);line-height:1;
  font-weight:600;letter-spacing:-.02em;color:var(--mint);
}
.stat__unit{font-size:.46em;letter-spacing:.04em;color:var(--fg-dim);margin-left:.12em}
.stat__label{font-family:var(--font-mono);font-size:12px;letter-spacing:.14em;color:var(--fg-dim)}

/* ---------------- 面包屑 ---------------- */
.crumb{padding-block:.6rem 1.2rem}
.crumb__list{
  display:flex;flex-wrap:wrap;align-items:center;gap:.55rem;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--fg-dim);
}
.crumb__item{display:flex;align-items:center;gap:.55rem}
.crumb__item+.crumb__item::before{content:"/";color:var(--stone)}
.crumb__link{color:var(--mint)}
.crumb__link:hover{text-decoration:underline;text-underline-offset:3px}
.crumb__item[aria-current="page"]{color:var(--fg)}

/* ---------------- 正文 ---------------- */
.prose{max-width:68ch;font-size:18px;line-height:1.9}
.prose>*+*{margin-top:1.15em}
.prose h2{margin-top:1.9em;font-size:clamp(1.4rem,2.2vw,1.9rem)}
.prose h3{margin-top:1.6em}
.prose ul,.prose ol{display:flex;flex-direction:column;gap:.5em}
.prose li{position:relative;padding-left:1.25em}
.prose li::before{content:"";position:absolute;left:0;top:.92em;width:7px;height:2px;background:var(--rust)}
.prose a{color:var(--mint);text-decoration:underline;text-underline-offset:3px}
.prose blockquote{border-left:3px solid var(--rust);padding-left:1.1rem;color:var(--fg-dim);font-size:1.02em}
.prose strong{font-weight:700}
.prose code{font-family:var(--font-mono);font-size:.9em;letter-spacing:.02em}
.prose hr{border:0;height:1px;background:var(--line);margin-block:2em}

/* ---------------- 图片容器基础 ---------------- */
.media{
  position:relative;overflow:hidden;isolation:isolate;
  border:1px solid var(--line);border-radius:2px;
  background:
    linear-gradient(180deg,rgba(95,242,194,.08),transparent 62%),
    repeating-linear-gradient(90deg,rgba(246,243,236,.07) 0 1px,transparent 1px 64px),
    repeating-linear-gradient(0deg,rgba(246,243,236,.05) 0 1px,transparent 1px 64px),
    linear-gradient(160deg,#14283D,#0B1726);
}
.media img{width:100%;height:100%;object-fit:cover;display:block}
.media--wide{aspect-ratio:16/9}
.media--tall{aspect-ratio:3/4}
.media--square{aspect-ratio:1/1}
.media--inset{aspect-ratio:4/3}
.media__cap{
  position:absolute;left:0;bottom:0;right:0;padding:.6rem .8rem;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;
  color:var(--paper);background:linear-gradient(0deg,rgba(11,23,38,.86),transparent);
}

/* =========================================================
   头部：观察窗框架
   ========================================================= */
.site-frame{position:relative;z-index:80}

.skip-link{
  position:fixed;top:8px;left:calc(var(--rail-w) + 12px);z-index:200;
  padding:.55rem .9rem;border-radius:2px;
  background:var(--mint);color:var(--ink);
  font-size:13px;font-weight:700;letter-spacing:.06em;
  transform:translateY(-180%);
  transition:transform .25s var(--ease);
}
.skip-link:focus{transform:translateY(0)}

/* 顶部横条 */
.frame-bar{
  position:fixed;top:0;left:var(--rail-w);right:0;height:var(--bar-h);
  display:flex;align-items:center;gap:clamp(.7rem,2vw,1.2rem);
  padding-inline:clamp(.9rem,3vw,1.6rem);
  background:rgba(11,23,38,.94);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);
  z-index:81;
}
.frame-bar__brand{display:none;align-items:center;gap:.55rem;min-width:0}
.frame-bar__dot{width:8px;height:8px;background:var(--rust);flex:none}
.frame-bar__word{font-size:14px;font-weight:800;letter-spacing:.08em;color:var(--paper);white-space:nowrap}
.frame-bar__line{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.24em;
  color:var(--mist);white-space:nowrap;
}
.frame-bar__trace{
  flex:1 1 auto;height:1px;min-width:2rem;
  background:linear-gradient(90deg,rgba(246,243,236,.26),rgba(246,243,236,0));
}
.frame-toggle{
  display:none;align-items:center;gap:.5rem;
  padding:.4rem .6rem;border:1px solid var(--line);border-radius:2px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;color:var(--paper);
  transition:border-color .25s var(--ease),color .25s var(--ease);
}
.frame-toggle:hover{border-color:var(--mint);color:var(--mint)}
.frame-toggle__bars{
  width:16px;height:10px;
  background:
    linear-gradient(var(--mint),var(--mint)) top/100% 2px no-repeat,
    linear-gradient(var(--mist),var(--mist)) center/100% 2px no-repeat,
    linear-gradient(var(--mist),var(--mist)) bottom/100% 2px no-repeat;
}
.site-frame[data-open="true"] .frame-toggle__bars{
  background:
    linear-gradient(var(--rust),var(--rust)) top/100% 2px no-repeat,
    linear-gradient(var(--rust),var(--rust)) center/100% 2px no-repeat,
    linear-gradient(var(--rust),var(--rust)) bottom/100% 2px no-repeat;
}

/* 左侧竖栏 */
.frame-rail{
  position:fixed;top:0;left:0;bottom:0;width:var(--rail-w);
  display:flex;flex-direction:column;align-items:stretch;gap:.6rem;
  padding:1.1rem .55rem 1.3rem;
  background:
    linear-gradient(180deg,rgba(20,40,61,.98),rgba(11,23,38,.99)),
    var(--ink);
  border-right:1px solid var(--line);
  z-index:82;
}
.frame-brand{display:flex;flex-direction:column;align-items:center;gap:.7rem;padding-top:.2rem}
.frame-brand__mark{
  display:grid;place-items:center;width:38px;height:38px;
  background:var(--rust);color:var(--paper);
  font-size:17px;font-weight:800;line-height:1;
  clip-path:polygon(0 0,100% 0,100% 72%,72% 100%,0 100%);
}
.frame-brand__name{font-size:13px;font-weight:800;letter-spacing:.14em;color:var(--paper)}
.frame-brand__line{
  writing-mode:vertical-rl;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.26em;
  color:var(--stone);padding-top:.3rem;
}

.frame-nav{flex:1 1 auto;padding-top:1.1rem;overflow-y:auto;overflow-x:hidden}
.frame-nav__list{display:flex;flex-direction:column;gap:.1rem;width:100%}
.frame-nav__item{width:100%}
.frame-nav__link{
  position:relative;display:block;
  padding:.58rem .3rem .58rem .85rem;
  font-size:13px;line-height:1.35;letter-spacing:.08em;font-weight:500;
  color:var(--mist);border-radius:2px;
  transition:color .3s var(--ease),background-color .3s var(--ease);
}
.frame-nav__link::before{
  content:"";position:absolute;left:0;top:1.02em;width:0;height:2px;
  background:var(--rust);transition:width .3s var(--ease);
}
.frame-nav__link:hover{color:var(--paper);background:rgba(246,243,236,.05)}
.frame-nav__link:hover::before{width:10px}
.frame-nav__link[aria-current="page"]{color:var(--paper);font-weight:700}
.frame-nav__link[aria-current="page"]::before{width:16px;height:3px}

.frame-cta{
  display:block;margin-top:auto;padding:.7rem .5rem;
  text-align:center;font-size:12px;font-weight:700;line-height:1.45;letter-spacing:.05em;
  color:var(--ink);background:var(--mint);border-radius:2px;
  transition:background-color .3s var(--ease),color .3s var(--ease);
}
.frame-cta:hover{background:var(--paper);color:var(--ink)}

/* 阅读进度 */
.frame-progress{
  position:fixed;top:calc(var(--bar-h) - 2px);left:var(--rail-w);right:0;height:2px;
  z-index:85;pointer-events:none;background:rgba(246,243,236,.06);
}
.frame-progress__bar{
  display:block;width:0;height:100%;
  background:linear-gradient(90deg,var(--rust),var(--mint));
}

/* =========================================================
   页脚：观察台铭牌
   ========================================================= */
.site-foot{
  position:relative;overflow:hidden;
  background:var(--ink);color:var(--paper);
  border-top:1px solid rgba(246,243,236,.14);
  padding-inline:var(--pad);
  padding-block:clamp(2.4rem,6vw,4.6rem) 0;
}
.site-foot::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:
    repeating-linear-gradient(180deg,rgba(184,194,204,.055) 0 1px,transparent 1px 26px),
    radial-gradient(120% 80% at 10% 0%,rgba(166,67,43,.22),transparent 62%);
}
.foot-inner{
  position:relative;
  display:grid;grid-template-columns:minmax(0,1.5fr) minmax(0,1fr);
  gap:clamp(2rem,5vw,4rem);
  padding-bottom:clamp(2rem,5vw,3.4rem);
}
.foot-lead{min-width:0}
.foot-brand{
  font-size:clamp(1.1rem,2vw,1.5rem);font-weight:800;line-height:1.35;
  letter-spacing:-.01em;max-width:22ch;color:var(--paper);
}
.foot-brand__div{color:var(--rust);margin-inline:.35rem;font-weight:400}
.foot-note{
  margin-top:1rem;max-width:44ch;
  font-size:14px;line-height:1.8;color:var(--mist);
}
.foot-reach{margin-top:1.4rem;display:flex;flex-direction:column;gap:.55rem;font-family:var(--font-mono);font-size:13px}
.foot-reach__item{display:flex;align-items:baseline;gap:.8rem;flex-wrap:wrap}
.foot-reach__k{min-width:3.4em;font-size:11px;letter-spacing:.16em;color:var(--stone)}
.foot-reach__v{color:var(--mist);line-height:1.7;font-size:12.5px}
.foot-copy{
  position:relative;
  padding:.05rem .1rem;
  font-family:var(--font-mono);font-size:13px;letter-spacing:.03em;
  color:var(--mint);border-bottom:1px dashed rgba(95,242,194,.55);
  transition:color .25s var(--ease),border-color .25s var(--ease);
}
.foot-copy:hover{color:var(--paper);border-bottom-color:var(--paper)}
.foot-copy::after{
  content:"已复制";position:absolute;left:0;bottom:calc(100% + .35rem);
  font-family:var(--font-mono);font-size:10px;letter-spacing:.12em;color:var(--gold);
  white-space:nowrap;pointer-events:none;opacity:0;transform:translateY(4px);
  transition:opacity .25s var(--ease),transform .25s var(--ease);
}
.foot-copy[data-state="copied"]::after{opacity:1;transform:none}
.foot-copy[data-state="failed"]{color:var(--gold);border-bottom-color:rgba(242,184,75,.6)}

.foot-cols{display:grid;grid-template-columns:1fr 1fr;gap:clamp(1.2rem,3vw,2.4rem)}
.foot-col{min-width:0}
.foot-col__title{
  margin-bottom:.9rem;
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.22em;color:var(--stone);
}
.foot-col__list{display:flex;flex-direction:column;gap:.55rem}
.foot-col__link{
  position:relative;display:inline-block;padding-left:0;
  font-size:15px;color:var(--mist);
  transition:color .25s var(--ease);
}
.foot-col__link::before{
  content:"";position:absolute;left:-.85rem;top:.75em;width:0;height:1px;
  background:var(--mint);transition:width .25s var(--ease);
}
.foot-col__link:hover{color:var(--paper)}
.foot-col__link:hover::before{width:.55rem}

.foot-plate{
  position:relative;display:flex;flex-wrap:wrap;align-items:center;
  gap:.55rem 1.6rem;
  padding-block:1.1rem 1.4rem;
  border-top:1px solid rgba(246,243,236,.12);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;color:var(--stone);
}
.foot-plate__copy{color:var(--mist)}
.foot-plate__icp{color:var(--stone)}
.foot-plate__mark{margin-left:auto;color:var(--stone)}

/* =========================================================
   滚动显现
   ========================================================= */
[data-reveal]{
  opacity:0;transform:translateY(18px);
  transition:opacity .6s var(--ease),transform .6s var(--ease);
}
[data-reveal].is-in{opacity:1;transform:none}

/* =========================================================
   响应式
   ========================================================= */
@media (max-width:1024px){
  .grid--split{grid-template-columns:1fr}
}

@media (max-width:900px){
  :root{--rail-w:0px;--bar-h:56px;--pad:clamp(1.1rem,5vw,2.4rem)}
  body{padding-left:0}
  .skip-link{left:12px}
  .frame-bar{left:0}
  .frame-bar__brand{display:flex}
  .frame-bar__line{display:none}
  .frame-toggle{display:inline-flex;margin-left:.2rem}

  .frame-rail{
    top:var(--bar-h);left:0;right:0;bottom:auto;width:auto;
    max-height:calc(100dvh - var(--bar-h));
    padding:1.1rem var(--pad) 1.5rem;
    gap:.8rem;
    border-right:0;border-bottom:1px solid var(--line);
    overflow-y:auto;
    background:rgba(11,23,38,.985);
    opacity:0;visibility:hidden;pointer-events:none;transform:translateY(-10px);
    transition:opacity .3s var(--ease),transform .3s var(--ease),visibility .3s;
    z-index:83;
  }
  .site-frame[data-open="true"] .frame-rail{
    opacity:1;visibility:visible;pointer-events:auto;transform:none;
  }
  .frame-brand{flex-direction:row;align-items:center;gap:.65rem;padding-top:0}
  .frame-brand__mark{width:32px;height:32px;font-size:15px}
  .frame-brand__name{letter-spacing:.12em}
  .frame-brand__line{display:none}
  .frame-nav{padding-top:.2rem;overflow:visible}
  .frame-nav__list{display:grid;grid-template-columns:1fr 1fr;gap:.15rem .9rem}
  .frame-nav__link{
    font-size:15px;padding:.72rem .5rem .72rem .95rem;
    border-bottom:1px solid var(--line);
  }
  .frame-nav__link::before{top:1.15em}
  .frame-cta{margin-top:.6rem;padding:.85rem 1rem;font-size:14px}

  .foot-inner{grid-template-columns:1fr;gap:2rem}
  .foot-plate__mark{margin-left:0}
}

@media (max-width:520px){
  body{font-size:16px}
  .prose{font-size:17px}
  .foot-cols{grid-template-columns:1fr}
  .frame-nav__list{grid-template-columns:1fr}
  .frame-nav__link{font-size:15px}
}

/* =========================================================
   动效降级
   ========================================================= */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  [data-reveal]{opacity:1;transform:none;transition:none}
  .skip-link,.frame-toggle,.frame-cta,.frame-nav__link,.btn,.foot-copy,.foot-col__link,.frame-rail{
    transition:none;
  }
}