/* ============================================================
   /assets/site.css — K1体育入口 全站共享样式
   夜场墨绿基底 · 暖白阅读层 · 信号橙数据点 · 草线绿结构线
   ============================================================ */

/* ---------- 1. tokens ---------- */
:root{
  --ink:#0A1E19;
  --ink-2:#102C25;
  --ink-3:#16382F;
  --paper:#F3EDE2;
  --paper-86:rgba(243,237,226,.86);
  --orange:#FF6A2B;
  --orange-soft:#FFB48C;
  --steel:#8AA1B4;
  --grass:#2E6B50;
  --glass:#1C3D34;
  --glass-72:rgba(28,61,52,.72);
  --night:#050D0B;
  --alert:#C4553A;
  --line-soft:rgba(46,107,80,.5);
  --hair:rgba(46,107,80,.32);

  --font-sans:"Source Han Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-mono:"JetBrains Mono","Roboto Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;

  --header-h:64px;
  --shell:min(1400px,calc(100% - 48px));
  --radius:2px;

  --fs-display:clamp(38px,5.6vw,72px);
  --fs-section:clamp(26px,3.2vw,40px);
  --fs-sub:clamp(19px,2vw,22px);
  --fs-body:17px;
  --fs-note:12px;

  --ease:cubic-bezier(.2,.7,.3,1);
}

/* ---------- 2. reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0}
h1,h2,h3,h4,p,figure,blockquote,ul,ol,dl,dd{margin:0}
ul[class],ol[class]{list-style:none;padding:0}
img,svg,video{max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
a{color:inherit}
table{border-collapse:collapse}

/* ---------- 3. 中文排版基线 ---------- */
body{
  font-family:var(--font-sans);
  font-size:var(--fs-body);
  line-height:1.75;
  color:var(--paper);
  background-color:var(--ink);
  background-image:radial-gradient(1100px 620px at 82% -12%,rgba(46,107,80,.22),transparent 68%);
  background-repeat:no-repeat;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
h1,h2,h3{font-weight:800;line-height:1.16;letter-spacing:-0.02em}
h1{font-size:var(--fs-display)}
h2{font-size:var(--fs-section)}
h3{font-size:var(--fs-sub);font-weight:700;letter-spacing:-0.01em}
strong,b{font-weight:700;color:var(--paper)}
small{font-size:13px;color:var(--steel)}
::selection{background:var(--orange);color:var(--ink)}

/* ---------- 4. 可访问性工具 ---------- */
.visually-hidden{
  position:absolute;width:1px;height:1px;margin:-1px;padding:0;
  overflow:hidden;clip:rect(0 0 0 0);clip-path:inset(50%);
  white-space:nowrap;border:0;
}
:where(a,button,summary,[tabindex]):focus-visible{
  outline:2px solid var(--orange);
  outline-offset:3px;
  border-radius:1px;
}
.skip-link{
  position:fixed;top:8px;left:50%;
  transform:translate(-50%,-180%);
  z-index:120;
  padding:10px 18px;
  background:var(--orange);color:var(--ink);
  font-size:14px;font-weight:700;letter-spacing:.02em;
  text-decoration:none;border-radius:var(--radius);
  transition:transform .18s var(--ease);
}
.skip-link:focus-visible{transform:translate(-50%,0);outline:2px solid var(--paper);outline-offset:2px}

/* ---------- 5. 头部 ---------- */
.site-header{
  position:fixed;
  inset-block-start:0;
  inset-inline:0;
  z-index:60;
  height:var(--header-h);
  background:transparent;
  border-block-end:1px solid transparent;
  transition:background-color .24s var(--ease),border-color .24s var(--ease);
}
.site-header[data-scrolled]{
  background:rgba(10,30,25,.94);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  border-block-end-color:var(--grass);
}
.header-inner{
  width:var(--shell);
  margin-inline:auto;
  height:100%;
  display:flex;
  align-items:center;
  gap:clamp(12px,2vw,28px);
}
.brand{
  display:flex;align-items:center;gap:10px;
  flex:0 0 auto;
  text-decoration:none;color:var(--paper);
}
.brand-mark{
  display:grid;place-items:center;
  width:34px;height:34px;
  font-family:var(--font-mono);
  font-size:14px;font-weight:700;letter-spacing:.04em;
  color:var(--ink);
  background:var(--orange);
  border-radius:1px;
}
.brand-text{display:flex;flex-direction:column;line-height:1.2}
.brand-name{font-size:15px;font-weight:800;letter-spacing:.02em}
.brand-sub{
  font-family:var(--font-mono);
  font-size:10px;letter-spacing:.1em;
  color:var(--steel);
}

/* 主导航 */
.site-nav{
  display:flex;
  align-items:center;
  margin-inline-start:auto;
}
.site-nav-list{
  display:flex;
  align-items:center;
  gap:clamp(10px,1.7vw,26px);
  margin:0;padding:0;
  list-style:none;
}
.nav-link{
  position:relative;
  display:inline-block;
  padding:6px 0;
  font-size:13.5px;
  letter-spacing:.04em;
  color:var(--steel);
  text-decoration:none;
  transition:color .18s var(--ease);
}
.nav-link::after{
  content:"";
  position:absolute;left:0;right:0;bottom:0;
  height:2px;background:var(--orange);
  transform:scaleX(0);transform-origin:left;
  transition:transform .2s var(--ease);
}
.nav-link:hover,.nav-link:focus-visible{color:var(--paper)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--paper);font-weight:700}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}
.site-nav-cta{display:none}

/* 操作区 */
.header-actions{
  display:flex;
  align-items:center;
  gap:12px;
  flex:0 0 auto;
}
.nav-toggle{
  display:none;
  width:44px;height:44px;padding:0;
  background:transparent;
  border:1px solid var(--line-soft);
  border-radius:var(--radius);
  color:var(--paper);
  cursor:pointer;
  transition:border-color .18s var(--ease);
}
.nav-toggle:hover{border-color:var(--orange)}
.nav-toggle-bars{
  display:block;position:relative;
  width:18px;height:2px;
  margin-inline:auto;
  background:currentColor;
  transition:background-color .18s var(--ease);
}
.nav-toggle-bars::before,
.nav-toggle-bars::after{
  content:"";
  position:absolute;left:0;
  width:18px;height:2px;
  background:currentColor;
  transition:transform .2s var(--ease);
}
.nav-toggle-bars::before{top:-6px}
.nav-toggle-bars::after{top:6px}
.site-header[data-open] .nav-toggle{border-color:var(--orange)}
.site-header[data-open] .nav-toggle-bars{background:transparent}
.site-header[data-open] .nav-toggle-bars::before{transform:translateY(6px) rotate(45deg)}
.site-header[data-open] .nav-toggle-bars::after{transform:translateY(-6px) rotate(-45deg)}

/* ---------- 6. 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  min-height:44px;
  padding:12px 20px;
  font-family:var(--font-sans);
  font-size:14px;font-weight:700;letter-spacing:.03em;
  line-height:1.2;
  text-decoration:none;
  border:1px solid transparent;
  border-radius:var(--radius);
  cursor:pointer;
  transition:background-color .18s var(--ease),color .18s var(--ease),
             border-color .18s var(--ease),transform .18s var(--ease);
}
.btn-primary{background:var(--orange);color:var(--ink)}
.btn-primary:hover{background:var(--orange-soft);color:var(--ink)}
.btn-ghost{background:transparent;color:var(--paper);border-color:var(--line-soft)}
.btn-ghost:hover{border-color:var(--orange);color:var(--orange-soft)}
.btn-sm{min-height:38px;padding:9px 16px;font-size:13px}

/* ---------- 7. 页脚 ---------- */
.site-footer{
  margin-block-start:clamp(56px,8vw,96px);
  background:linear-gradient(180deg,rgba(5,13,11,0) 0%,var(--night) 32%);
  border-block-start:1px solid var(--hair);
  color:var(--steel);
  font-size:14px;
  line-height:1.7;
}
.footer-inner{
  width:var(--shell);
  margin-inline:auto;
  padding-block:clamp(36px,5vw,56px) clamp(24px,3vw,32px);
  display:grid;
  grid-template-columns:minmax(0,1.05fr) minmax(0,1.5fr);
  gap:clamp(28px,4vw,64px);
}
.footer-lead{display:flex;flex-direction:column;gap:10px}
.footer-brand{
  font-size:clamp(22px,2.8vw,30px);
  font-weight:800;
  letter-spacing:-0.02em;
  line-height:1.2;
  color:var(--paper);
}
.footer-tagline{font-size:15px;color:var(--steel)}
.footer-stamp{
  margin-block-start:6px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  color:var(--grass);
}
.footer-cols{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:clamp(18px,3vw,40px);
}
.footer-col{min-width:0}
.footer-col-title{
  margin:0 0 12px;
  font-size:12px;
  font-weight:700;
  letter-spacing:.18em;
  color:var(--paper);
}
.footer-links{
  display:flex;
  flex-direction:column;
  gap:8px;
  margin:0;padding:0;
  list-style:none;
}
.footer-links a{
  font-size:14px;
  color:var(--steel);
  text-decoration:none;
  transition:color .18s var(--ease);
}
.footer-links a:hover,.footer-links a:focus-visible{color:var(--orange-soft)}
.footer-meta{
  width:var(--shell);
  margin-inline:auto;
  padding-block:18px 36px;
  border-block-start:1px solid var(--hair);
  display:flex;
  flex-wrap:wrap;
  justify-content:space-between;
  align-items:baseline;
  gap:10px 24px;
  font-size:13px;
  color:var(--steel);
}
.footer-contact{margin:0;word-break:break-word}
.footer-legal{
  margin:0;
  display:flex;
  flex-wrap:wrap;
  gap:8px 18px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.03em;
  color:var(--grass);
}
.footer-copy{color:var(--steel)}

/* ---------- 8. 布局容器 ---------- */
#main-content{padding-block-start:var(--header-h)}
.container{width:var(--shell);margin-inline:auto}
.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:clamp(16px,2vw,32px);
}
.grid-12 .col-main{grid-column:span 7;min-width:0}
.grid-12 .col-note{grid-column:span 2;min-width:0}
.grid-12 .col-visual{grid-column:span 3;min-width:0}

/* ---------- 9. 章节与文本组件 ---------- */
.section{padding-block:clamp(40px,6vw,76px)}
.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:10px 18px;
  margin-block-end:clamp(18px,2.4vw,28px);
}
.section-head h2{font-size:var(--fs-section)}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:700;
  letter-spacing:.18em;
  color:var(--orange);
}
.annotation{
  display:inline-block;
  writing-mode:vertical-rl;
  font-family:var(--font-mono);
  font-size:var(--fs-note);
  letter-spacing:.18em;
  color:var(--steel);
}
.chapter-num{
  display:block;
  font-family:var(--font-mono);
  font-weight:700;
  font-size:clamp(44px,6vw,80px);
  line-height:1;
  letter-spacing:-0.03em;
  color:rgba(243,237,226,.16);
}
.rule{
  height:1px;
  margin:0;
  border:0;
  background:var(--hair);
}
.metric{
  font-family:var(--font-mono);
  font-weight:700;
  font-variant-numeric:tabular-nums;
  letter-spacing:-0.01em;
}
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:2px 8px;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:700;
  letter-spacing:.1em;
  color:var(--orange);
  border:1px solid rgba(255,106,43,.42);
  border-radius:var(--radius);
  white-space:nowrap;
}
.prose{max-width:66ch}
.prose p{margin-block:0 1em;color:var(--paper-86)}
.prose p:last-child{margin-block-end:0}
.prose strong{color:var(--paper)}
.prose a{
  color:var(--orange-soft);
  text-decoration:underline;
  text-underline-offset:3px;
  text-decoration-color:rgba(255,180,140,.5);
}
.prose a:hover{color:var(--orange);text-decoration-color:var(--orange)}

/* ---------- 10. 卡片 / 玻璃层 ---------- */
.card{
  background:var(--ink-2);
  border:1px solid var(--hair);
  border-radius:var(--radius);
  padding:clamp(16px,2vw,24px);
  transition:transform .2s var(--ease),border-color .2s var(--ease),background-color .2s var(--ease);
}
.card:hover,.card:focus-within{
  transform:translateY(-4px);
  border-color:var(--line-soft);
  background:var(--ink-3);
}
.glass{
  background:var(--glass-72);
  border:1px solid var(--line-soft);
  border-radius:var(--radius);
  -webkit-backdrop-filter:blur(12px);
  backdrop-filter:blur(12px);
  transition:background-color .2s var(--ease),transform .2s var(--ease);
}
.glass:hover,.glass:focus-within{
  background:rgba(28,61,52,.9);
  transform:translateY(-4px);
}

/* ---------- 11. 图片容器基础规则 ---------- */
.media-frame{
  position:relative;
  display:block;
  overflow:hidden;
  aspect-ratio:16 / 9;
  background:linear-gradient(150deg,var(--ink-3) 0%,var(--ink-2) 46%,#071713 100%);
  border:1px solid var(--hair);
  border-radius:var(--radius);
}
.media-frame img{
  display:block;
  width:100%;height:100%;
  object-fit:cover;
  filter:saturate(.86) contrast(1.02);
}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--tall{aspect-ratio:3 / 4}
.media-frame--square{aspect-ratio:1 / 1}
.media-frame--shade::after{
  content:"";
  position:absolute;inset:0;
  background:linear-gradient(180deg,rgba(5,13,11,0) 42%,rgba(5,13,11,.72) 100%);
  pointer-events:none;
}

/* ---------- 12. 面包屑 ---------- */
.breadcrumb{padding-block:20px 0}
.breadcrumb-list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  margin:0;padding:0;
  list-style:none;
  font-size:13px;
  color:var(--steel);
}
.breadcrumb-item{display:inline-flex;align-items:center;gap:8px}
.breadcrumb-item a{
  color:var(--steel);
  text-decoration:none;
  border-block-end:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.breadcrumb-item a:hover,.breadcrumb-item a:focus-visible{
  color:var(--orange-soft);
  border-block-end-color:var(--line-soft);
}
.breadcrumb-item + .breadcrumb-item::before{
  content:"/";
  color:var(--grass);
}

/* ---------- 13. 滚动进度条（JS 注入） ---------- */
.scroll-progress{
  position:fixed;
  inset-block-start:0;
  inset-inline-start:0;
  z-index:80;
  width:100%;
  height:2px;
  background:var(--orange);
  transform:scaleX(0);
  transform-origin:0 50%;
  pointer-events:none;
  transition:transform .1s linear;
}

/* ---------- 14. 显现 ---------- */
html.js-ready [data-reveal]{
  opacity:0;
  transform:translateY(8px);
  transition:opacity .2s var(--ease),transform .2s var(--ease);
}
html.js-ready [data-reveal].is-revealed{
  opacity:1;
  transform:none;
}

/* ---------- 15. 平板 ---------- */
@media (max-width:1100px){
  .site-nav-list{gap:12px}
  .nav-link{font-size:13px}
  .header-cta{display:none}
  .nav-toggle{display:inline-flex;align-items:center;justify-content:center}
  .site-nav{
    position:fixed;
    inset-block-start:var(--header-h);
    inset-inline:0;
    display:block;
    margin:0;
    padding:8px 0 20px;
    max-height:calc(100dvh - var(--header-h));
    overflow-y:auto;
    background:rgba(6,20,16,.97);
    -webkit-backdrop-filter:blur(14px);
    backdrop-filter:blur(14px);
    border-block-end:1px solid var(--line-soft);
    box-shadow:0 24px 48px rgba(0,0,0,.45);
    opacity:0;
    visibility:hidden;
    transform:translateY(-10px);
    transition:opacity .2s var(--ease),transform .2s var(--ease),visibility .2s;
  }
  .site-header[data-open] .site-nav{
    opacity:1;
    visibility:visible;
    transform:none;
  }
  .site-nav-list{display:block;padding:0}
  .nav-link{
    display:block;
    padding:14px 24px;
    font-size:16px;
    color:var(--paper);
    border-block-end:1px solid rgba(46,107,80,.3);
  }
  .nav-link::after{display:none}
  .nav-link[aria-current="page"]{
    color:var(--orange-soft);
    box-shadow:inset 3px 0 0 var(--orange);
  }
  .site-nav-cta{display:block;padding:18px 24px 0}
  .site-nav-cta .btn{width:100%}
  .header-actions{margin-inline-start:auto}
  .grid-12 .col-main,
  .grid-12 .col-note,
  .grid-12 .col-visual{grid-column:1 / -1}
}

/* ---------- 16. 手机 ---------- */
@media (max-width:860px){
  .footer-inner{grid-template-columns:1fr;gap:32px}
  .footer-cols{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media (max-width:600px){
  :root{--shell:calc(100% - 32px)}
  .brand-sub{display:none}
  .brand-name{font-size:14px}
  .annotation{writing-mode:horizontal-tb}
  .footer-cols{grid-template-columns:1fr 1fr;gap:24px}
  .footer-meta{flex-direction:column;align-items:flex-start;gap:10px}
  .footer-legal{gap:6px 14px}
}

/* ---------- 17. reduced motion ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  html.js-ready [data-reveal]{opacity:1;transform:none}
  .card:hover,.card:focus-within,
  .glass:hover,.glass:focus-within{transform:none}
}