/* ============================================================
   长城体育 · 共享样式 /assets/site.css
   边关烽火 × 数据看台：近单色 + 单一暖橙，直角细线精密网格
   ============================================================ */

/* ---------- reset ---------- */
*,
*::before,
*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:132px}
body,h1,h2,h3,h4,h5,p,ol,ul,dl,dd,figure,blockquote{margin:0}
ol,ul{list-style:none;padding:0}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
img,svg,video{display:block;max-width:100%}
table{border-collapse:collapse;width:100%}
hr{border:0}

/* ---------- 变量 ---------- */
:root{
  --c-ink:#14161A;
  --c-rampart:#22262B;
  --c-brick:#33383E;
  --c-mid:#6A7076;
  --c-stone:#E4E6E8;
  --c-paper:#F4F2ED;
  --c-flame:#E2662A;
  --c-ember:#F0A277;
  --c-field:#4E7A57;
  --c-deep:#1B2A3A;

  --ink-body:#2C3036;
  --on-dark:#E4E6E8;
  --on-dark-dim:rgba(228,230,232,.64);
  --on-dark-faint:rgba(228,230,232,.4);
  --line-dark:rgba(228,230,232,.16);
  --line-light:rgba(51,56,62,.20);
  --wash-flame:rgba(226,102,42,.07);

  --font-sans:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;

  --shell-w:1280px;
  --gutter:clamp(18px,4vw,48px);
  --dur:200ms;
  --ease:cubic-bezier(.22,.61,.36,1);
  --header-upper-h:62px;
  --header-lower-h:56px;
}

/* ---------- 基础排版 ---------- */
body{
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.8;
  color:var(--ink-body);
  background:var(--c-paper);
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
h1,h2,h3,h4{color:var(--c-ink);font-weight:900;line-height:1.18;letter-spacing:-.02em}
strong{font-weight:700;color:var(--c-ink)}
a,button{transition:color var(--dur) var(--ease),background-color var(--dur) var(--ease),border-color var(--dur) var(--ease),opacity var(--dur) var(--ease)}
:focus-visible{outline:2px solid var(--c-flame);outline-offset:3px}
::selection{background:var(--c-flame);color:var(--c-ink)}

.display-1{font-size:clamp(40px,7vw,96px);font-weight:900;line-height:1.02;letter-spacing:-.02em;color:var(--c-ink)}
.display-2{font-size:clamp(30px,4.4vw,56px);font-weight:900;line-height:1.08;letter-spacing:-.02em;color:var(--c-ink)}
.display-3{font-size:clamp(21px,2.6vw,32px);font-weight:900;line-height:1.2;letter-spacing:-.01em;color:var(--c-ink)}

.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.num-l{font-family:var(--font-mono);font-variant-numeric:tabular-nums;font-size:clamp(28px,4vw,72px);font-weight:700;line-height:1;letter-spacing:-.02em;color:var(--c-ink)}

.annotation{font-size:12px;letter-spacing:.3em;color:var(--c-mid);text-transform:uppercase}
.annotation--vertical{writing-mode:vertical-rl;text-orientation:mixed;letter-spacing:.3em}

/* ---------- 布局骨架 ---------- */
.shell{
  width:100%;
  max-width:var(--shell-w);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.section{padding-block:clamp(48px,7vw,96px)}
.section--paper{background:var(--c-paper)}
.section--stone{background:var(--c-stone)}
.section--dark{background:var(--c-ink);color:var(--on-dark)}
.section--deep{background:var(--c-deep);color:var(--on-dark)}
.section--dark h2,.section--dark h3,.section--deep h2,.section--deep h3{color:#fff}

.grid{display:grid;gap:clamp(20px,3vw,36px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--split{grid-template-columns:minmax(0,1.15fr) minmax(0,.85fr)}
.rule{height:1px;width:100%;background:var(--line-light)}
.visually-hidden{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}

/* ---------- 章节色带 ---------- */
.chapter-band{
  display:flex;
  align-items:flex-start;
  gap:clamp(14px,2vw,24px);
  border-top:1px solid var(--line-light);
  padding-top:16px;
  margin-bottom:clamp(24px,3.4vw,44px);
}
.section--dark .chapter-band,
.section--deep .chapter-band{border-top-color:var(--line-dark)}
.chapter-band__index{
  font-family:var(--font-mono);
  font-size:14px;
  font-weight:700;
  letter-spacing:.14em;
  color:var(--c-flame);
  padding-top:.35em;
  flex:none;
}
.chapter-band__body{flex:1 1 auto;min-width:0}
.chapter-band__title{
  font-size:clamp(20px,2.4vw,30px);
  font-weight:900;
  line-height:1.22;
  letter-spacing:-.01em;
  color:var(--c-ink);
}
.section--dark .chapter-band__title,
.section--deep .chapter-band__title{color:#fff}
.chapter-band__note{
  writing-mode:vertical-rl;
  text-orientation:mixed;
  font-size:12px;
  letter-spacing:.3em;
  color:var(--c-mid);
  align-self:flex-start;
  flex:none;
  max-height:120px;
}

/* ---------- 面包屑 ---------- */
.breadcrumb{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
  font-size:12px;
  letter-spacing:.16em;
  color:var(--c-mid);
  margin-bottom:clamp(20px,3vw,32px);
}
.breadcrumb__link{color:var(--c-mid)}
.breadcrumb__link:hover{color:var(--c-flame)}
.breadcrumb__sep{color:var(--c-brick);opacity:.6}
.breadcrumb [aria-current="page"]{color:var(--c-ink)}

/* ---------- 正文长文 ---------- */
.prose{max-width:38em;font-size:17px;line-height:1.85;color:var(--ink-body)}
.prose > * + *{margin-top:1.05em}
.prose h2{font-size:clamp(20px,2.2vw,26px);margin-top:1.8em}
.prose h3{font-size:18px;margin-top:1.5em}
.prose ul,.prose ol{margin-top:1.05em}
.prose li{position:relative;padding-left:20px}
.prose li + li{margin-top:.5em}
.prose li::before{content:"";position:absolute;left:0;top:.78em;width:9px;height:1px;background:var(--c-flame)}
.prose a{color:var(--c-flame);border-bottom:1px solid rgba(226,102,42,.4)}
.prose a:hover{border-bottom-color:var(--c-flame)}

/* ---------- 面板 / 标签 ---------- */
.panel{
  border:1px solid var(--line-light);
  background:#fff;
  padding:clamp(20px,3vw,34px);
}
.panel--dark{background:var(--c-deep);border-color:var(--line-dark);color:var(--on-dark)}
.panel--dark h3{color:#fff}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 9px;
  border:1px solid var(--line-light);
  font-size:11px;
  letter-spacing:.18em;
  color:var(--c-mid);
  line-height:1.6;
}
.tag--field{border-color:rgba(78,122,87,.55);color:var(--c-field)}
.tag--flame{border-color:rgba(226,102,42,.55);color:var(--c-flame)}

/* ---------- 图例式列表 ---------- */
.legend-list{border-top:1px solid var(--line-light)}
.section--dark .legend-list,.section--deep .legend-list{border-top-color:var(--line-dark)}
.legend-item{
  display:grid;
  grid-template-columns:auto auto minmax(0,1fr) auto;
  align-items:center;
  gap:clamp(10px,1.6vw,20px);
  padding:15px 10px 15px 0;
  border-bottom:1px solid var(--line-light);
  transition:background-color var(--dur) var(--ease),padding-left var(--dur) var(--ease);
}
.section--dark .legend-item,.section--deep .legend-item{border-bottom-color:var(--line-dark)}
.legend-item:hover{background:var(--wash-flame);padding-left:8px}
.legend-item__index{font-family:var(--font-mono);font-size:12px;letter-spacing:.12em;color:var(--c-mid)}
.legend-item__swatch{width:10px;height:10px;background:var(--c-flame);transition:transform var(--dur) var(--ease)}
.legend-item__swatch--field{background:var(--c-field)}
.legend-item__swatch--deep{background:var(--c-deep)}
.legend-item:hover .legend-item__swatch{transform:scale(1.35)}
.legend-item__title{font-size:16px;font-weight:500;color:var(--c-ink)}
.section--dark .legend-item__title,.section--deep .legend-item__title{color:var(--on-dark)}
.legend-item__meta{font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:var(--c-mid);white-space:nowrap}

/* ---------- 日期轴 ---------- */
.axis{
  display:flex;
  align-items:stretch;
  overflow-x:auto;
  border-top:1px solid var(--line-light);
  padding-top:14px;
  -webkit-overflow-scrolling:touch;
}
.section--dark .axis,.section--deep .axis{border-top-color:var(--line-dark)}
.axis__tick{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--c-mid);
  padding:2px 16px;
  white-space:nowrap;
  position:relative;
}
.axis__tick + .axis__tick{border-left:1px solid var(--line-light)}
.section--dark .axis__tick + .axis__tick,
.section--deep .axis__tick + .axis__tick{border-left-color:var(--line-dark)}

/* ---------- 按钮与链接 ---------- */
.btn-line{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:9px 16px;
  border:1px solid var(--line-dark);
  font-size:13px;
  font-weight:500;
  letter-spacing:.16em;
  color:var(--on-dark);
  white-space:nowrap;
}
.btn-line::after{content:"";width:14px;height:1px;background:currentColor;transition:width var(--dur) var(--ease)}
.btn-line:hover{border-color:var(--c-flame);color:var(--c-flame)}
.btn-line:hover::after{width:24px}

.btn-flame{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:12px 22px;
  background:var(--c-flame);
  border:1px solid var(--c-flame);
  color:var(--c-ink);
  font-size:14px;
  font-weight:700;
  letter-spacing:.12em;
}
.btn-flame:hover{background:var(--c-ember);border-color:var(--c-ember)}

.link-arrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-size:14px;
  font-weight:500;
  letter-spacing:.04em;
  color:var(--c-flame);
}
.link-arrow::after{content:"→";transition:transform var(--dur) var(--ease)}
.link-arrow:hover::after{transform:translateX(5px)}

/* ---------- 图片框（页面阶段放置图片） ---------- */
.media-frame{
  position:relative;
  width:100%;
  background:var(--c-rampart);
  border:1px solid var(--line-light);
  overflow:hidden;
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(to right,rgba(228,230,232,.07) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(228,230,232,.07) 1px,transparent 1px);
  background-size:44px 44px;
}
.media-frame--16x9{aspect-ratio:16/9}
.media-frame--4x3{aspect-ratio:4/3}
.media-frame--1x1{aspect-ratio:1/1}
.media-frame__img{width:100%;height:100%;object-fit:cover;filter:grayscale(.12) contrast(1.06)}
.media-frame__caption{
  margin-top:10px;
  font-size:12px;
  letter-spacing:.16em;
  color:var(--c-mid);
}

/* ---------- 滚动显现 ---------- */
html.js [data-reveal]{opacity:0;transform:translateY(12px)}
html.js [data-reveal].is-visible{
  opacity:1;
  transform:none;
  transition:opacity 200ms var(--ease),transform 200ms var(--ease);
}

/* ============================================================
   页头
   ============================================================ */
.site-header{
  position:sticky;
  top:0;
  z-index:60;
  background:var(--c-ink);
  color:var(--on-dark);
  border-bottom:1px solid var(--line-dark);
}
.skip-link{
  position:absolute;
  left:var(--gutter);
  top:-120px;
  z-index:99;
  background:var(--c-flame);
  color:var(--c-ink);
  font-size:13px;
  font-weight:700;
  letter-spacing:.14em;
  padding:10px 18px;
  transition:top var(--dur) var(--ease);
}
.skip-link:focus{top:10px}

/* 上层：品牌说明 */
.header-upper{
  background:var(--c-rampart);
  border-bottom:1px solid var(--line-dark);
  overflow:hidden;
  max-height:120px;
  transition:max-height var(--dur) var(--ease),opacity var(--dur) var(--ease);
}
.site-header[data-condensed="true"] .header-upper{
  max-height:0;
  opacity:0;
  border-bottom-color:transparent;
}
.header-upper__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
  min-height:var(--header-upper-h);
}

.brand{display:inline-flex;align-items:center;gap:12px}
.brand__mark{display:flex;flex-direction:column;gap:3px;width:24px;flex:none}
.brand__brick{display:block;height:4px;width:100%;background:var(--c-mid)}
.brand__brick:nth-child(2){width:66%}
.brand__brick--flame{width:84%;background:var(--c-flame)}
.brand__text{display:flex;flex-direction:column;line-height:1.25}
.brand__name{font-size:19px;font-weight:900;letter-spacing:.08em;color:#fff}
.brand__tag{font-size:11px;letter-spacing:.28em;color:var(--on-dark-faint)}
.brand:hover .brand__name{color:var(--c-ember)}
.brand:hover .brand__brick--flame{background:var(--c-ember)}

.header-upper__meta{display:flex;align-items:center;gap:clamp(12px,1.6vw,20px)}
.meta-item{display:inline-flex;align-items:baseline;gap:8px}
.meta-label{font-size:11px;letter-spacing:.24em;color:var(--on-dark-faint)}
.meta-value{font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--on-dark-dim)}
.meta-sep{display:inline-block;width:1px;height:12px;background:var(--line-dark)}

/* 下层：烽火台序列导航 */
.header-lower{background:var(--c-ink)}
.header-lower__inner{
  position:relative;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:18px;
  min-height:var(--header-lower-h);
}
.header-lower__caption{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.3em;
  color:var(--on-dark-faint);
  white-space:nowrap;
  flex:none;
}
.site-nav{flex:1 1 auto;display:flex;justify-content:flex-end}
.nav-rampart{display:flex;align-items:center;flex-wrap:wrap}
.nav-node{display:flex;align-items:center}
.nav-node + .nav-node::before{
  content:"";
  display:block;
  width:clamp(12px,2vw,32px);
  height:1px;
  background:var(--line-dark);
  transition:background-color var(--dur) var(--ease);
}
.nav-link{
  position:relative;
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:10px 4px;
  font-size:15px;
  font-weight:500;
  letter-spacing:.06em;
  color:var(--on-dark-dim);
}
.nav-link__node{
  width:7px;
  height:7px;
  flex:none;
  border:1px solid var(--c-mid);
  background:transparent;
  transition:background-color var(--dur) var(--ease),border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.nav-link__index{font-family:var(--font-mono);font-size:10px;letter-spacing:.1em;color:var(--on-dark-faint)}
.nav-link__label{white-space:nowrap}
.nav-link::after{
  content:"";
  position:absolute;
  left:0;
  right:0;
  bottom:4px;
  height:1px;
  background:var(--c-flame);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform var(--dur) var(--ease);
}
.nav-link:hover{color:#fff}
.nav-link:hover .nav-link__node{border-color:var(--c-flame);background:var(--c-flame)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:#fff}
.nav-link[aria-current="page"] .nav-link__node{
  border-color:var(--c-flame);
  background:var(--c-flame);
  box-shadow:0 0 0 3px rgba(226,102,42,.2);
}
.nav-link[aria-current="page"] .nav-link__index{color:var(--c-flame)}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}

/* 移动导航按钮 */
.nav-toggle{
  display:none;
  align-items:center;
  gap:12px;
  padding:10px 0;
  font-size:12px;
  letter-spacing:.28em;
  color:var(--on-dark);
}
.nav-toggle__bar{position:relative;display:block;width:22px;height:1px;background:var(--on-dark);transition:background-color var(--dur) var(--ease)}
.nav-toggle__bar::before,
.nav-toggle__bar::after{
  content:"";
  position:absolute;
  left:0;
  width:22px;
  height:1px;
  background:inherit;
  transition:transform var(--dur) var(--ease),background-color var(--dur) var(--ease);
}
.nav-toggle__bar::before{top:-6px}
.nav-toggle__bar::after{top:6px}
.nav-toggle[aria-expanded="true"]{color:var(--c-flame)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar{background:transparent}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar::before{background:var(--c-flame);transform:translateY(6px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar::after{background:var(--c-flame);transform:translateY(-6px) rotate(-45deg)}

/* 阅读进度 */
.scroll-progress{position:absolute;left:0;right:0;bottom:-1px;height:2px;pointer-events:none}
.scroll-progress__bar{
  display:block;
  width:100%;
  height:100%;
  background:var(--c-flame);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform 140ms linear;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer{
  background:var(--c-brick);
  color:var(--on-dark-dim);
  border-top:1px solid var(--c-flame);
}
.footer__inner{
  display:grid;
  grid-template-columns:1.5fr repeat(4,minmax(0,1fr));
  gap:clamp(24px,3vw,40px);
  padding-block:clamp(40px,5vw,64px) clamp(28px,3.4vw,44px);
}
.footer__brand{display:flex;flex-direction:column;gap:10px}
.footer__brand-name{font-size:22px;font-weight:900;letter-spacing:.1em;color:#fff}
.footer__brand-note{font-size:13px;line-height:1.8;color:var(--on-dark-dim);max-width:22em}
.footer__brand-note--dim{color:var(--on-dark-faint);font-size:12px;letter-spacing:.12em}
.footer__icp{
  margin-top:6px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--on-dark-faint);
}
.footer__group{min-width:0}
.footer__group-title{
  display:flex;
  align-items:center;
  gap:8px;
  font-size:12px;
  font-weight:700;
  letter-spacing:.3em;
  color:var(--c-ember);
  margin-bottom:16px;
}
.footer__group-title::after{content:"";flex:1 1 auto;height:1px;background:rgba(226,102,42,.35)}
.footer__list li + li{margin-top:10px}
.footer__link{
  display:inline-flex;
  align-items:center;
  gap:9px;
  font-size:14px;
  color:var(--on-dark-dim);
}
.footer__link::before{
  content:"";
  width:6px;
  height:6px;
  flex:none;
  border:1px solid var(--c-mid);
  transition:background-color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.footer__link:hover{color:var(--c-flame)}
.footer__link:hover::before{background:var(--c-flame);border-color:var(--c-flame)}
.footer__contact{margin-top:18px;display:grid;gap:2px}
.footer__contact dt{font-size:11px;letter-spacing:.24em;color:var(--on-dark-faint);margin-top:8px}
.footer__contact dd{font-size:13px;line-height:1.7;color:var(--on-dark-dim);word-break:break-word}
.footer__base{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 24px;
  border-top:1px solid var(--line-dark);
  padding-block:18px;
  font-size:12px;
  letter-spacing:.08em;
  color:var(--on-dark-faint);
}
.footer__base span{font-family:var(--font-mono)}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width:1100px){
  .footer__inner{grid-template-columns:1fr 1fr 1fr;row-gap:32px}
  .footer__brand{grid-column:1 / -1}
}
@media (max-width:920px){
  html{scroll-padding-top:76px}
  .header-lower__caption{display:none}
  .nav-toggle{display:inline-flex;margin-left:auto}
  [data-nav]{display:none;flex:0 0 auto}
  [data-nav][data-open="true"]{
    display:block;
    position:absolute;
    left:0;
    right:0;
    top:100%;
    background:var(--c-rampart);
    border-top:1px solid var(--c-flame);
    border-bottom:1px solid var(--line-dark);
    padding:12px var(--gutter) 22px;
    max-height:calc(100vh - 110px);
    overflow-y:auto;
  }
  .nav-rampart{flex-direction:column;align-items:stretch}
  .nav-node + .nav-node::before{width:1px;height:14px;margin-left:5px}
  .nav-link{width:100%;padding:12px 0;font-size:16px}
  .nav-link::after{bottom:6px}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:820px){
  .header-upper__meta .meta-item,
  .header-upper__meta .meta-sep{display:none}
}
@media (max-width:720px){
  .grid--2,.grid--3,.grid--split{grid-template-columns:1fr}
  .footer__inner{grid-template-columns:1fr 1fr;row-gap:28px}
  .footer__brand{grid-column:1 / -1}
  .chapter-band__note{display:none}
  .footer__base{justify-content:flex-start}
}
@media (max-width:440px){
  .brand__tag{display:none}
  .btn-line{padding:8px 12px;letter-spacing:.1em}
  .footer__inner{grid-template-columns:1fr}
}

/* ============================================================
   动效偏好
   ============================================================ */
@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}
  .scroll-progress__bar{transition:none}
}