/* ============================================================
   /assets/site.css — 爱体育官网 共享外壳
   夜训蓝 + 深场绿 + 米白阅读带；细线、坐标、内容轨道
   ============================================================ */

/* ---------- reset ---------- */
*,
*::before,
*::after{box-sizing:border-box}

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--bar) + 16px);
}

body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dt,dd,fieldset{margin:0;padding:0}
ul,ol{list-style:none}
img,svg,video{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
button{background:none;border:0;cursor:pointer;font:inherit;color:inherit}
input,select,textarea{font:inherit;color:inherit}

/* ---------- tokens ---------- */
:root{
  --ink:#0B1B2B;
  --field:#123B2E;
  --moss:#3E6B52;
  --stone:#8A8F8A;
  --clay:#B86B4B;
  --paper:#F3EFE6;
  --flame:#FF6A1A;
  --signal:#FFD23F;
  --white:#FFFFFF;
  --black:#050B10;

  --rail:88px;
  --bar:62px;
  --maxw:1320px;

  --line:rgba(243,239,230,.14);
  --line-strong:rgba(243,239,230,.28);
  --line-dark:rgba(5,11,16,.14);
  --muted:rgba(243,239,230,.66);
  --shadow-soft:0 1px 0 rgba(5,11,16,.45), 0 18px 40px -32px rgba(5,11,16,.9);

  --font-sans:'Noto Sans SC','PingFang SC','Microsoft YaHei',sans-serif;
  --font-mono:'IBM Plex Mono','SFMono-Regular',Consolas,monospace;

  --ease:cubic-bezier(.2,.6,.2,1);
  --t:160ms;
}

@media (min-width:1024px){
  html{scroll-padding-top:24px}
}

/* ---------- base ---------- */
body{
  font-family:var(--font-sans);
  font-size:16px;
  font-weight:400;
  line-height:1.75;
  color:var(--paper);
  background:var(--ink);
  padding-top:var(--bar);
  -webkit-font-smoothing:antialiased;
}

@media (min-width:1024px){
  body{padding-top:0;padding-left:var(--rail)}
}

body.nav-open{overflow:hidden}

:focus-visible{
  outline:2px solid var(--flame);
  outline-offset:3px;
  box-shadow:0 0 0 4px rgba(5,11,16,.55);
}

.visually-hidden{
  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;
}

/* ---------- skip link ---------- */
.skip-link{
  position:fixed;
  top:10px;left:10px;
  z-index:300;
  padding:10px 18px;
  background:var(--signal);
  color:var(--black);
  font-size:14px;
  font-weight:700;
  border-radius:2px;
  transform:translateY(-180%);
  transition:transform var(--t) var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{transform:translateY(0)}

@media (min-width:1024px){
  .skip-link{left:calc(var(--rail) + 10px)}
}

/* ============================================================
   HEADER
   ============================================================ */
.site-header{
  position:fixed;
  top:0;left:0;right:0;
  z-index:100;
}

@media (min-width:1024px){
  .site-header{position:static}
}

/* --- 移动端顶栏 --- */
.topbar{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  height:var(--bar);
  padding:0 18px;
  background:rgba(11,27,43,.97);
  border-bottom:1px solid var(--line);
  box-shadow:0 10px 30px -24px rgba(5,11,16,1);
}

.topbar__meta{display:flex;align-items:center;gap:12px}

.topbar__ver{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  color:var(--signal);
  border:1px solid rgba(255,210,63,.42);
  border-radius:2px;
  padding:2px 7px;
  line-height:1.4;
}

@media (min-width:1024px){
  .topbar{display:none}
}

/* --- 品牌 --- */
.brand{
  display:inline-flex;
  align-items:center;
  gap:10px;
  color:var(--paper);
}

.brand__mark{
  display:grid;
  place-items:center;
  width:34px;height:34px;
  flex:0 0 auto;
  background:var(--signal);
  color:var(--black);
  font-size:17px;
  font-weight:800;
  line-height:1;
  border-radius:2px;
}

.brand__name{
  font-size:15px;
  font-weight:800;
  letter-spacing:.06em;
  line-height:1.2;
}

/* --- 抽屉按钮 --- */
.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:9px;
  padding:8px 11px;
  border:1px solid var(--line-strong);
  border-radius:2px;
  color:var(--paper);
  transition:border-color var(--t) var(--ease),color var(--t) var(--ease);
}
.nav-toggle:hover,
.nav-toggle:focus-visible{border-color:var(--flame);color:var(--flame)}

.nav-toggle__bars{display:grid;gap:4px;width:18px}
.nav-toggle__bars i{display:block;height:2px;background:currentColor;border-radius:1px}
.nav-toggle__bars i:nth-child(2){width:70%}

.nav-toggle__text{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
}

/* --- 导航（移动端 = 抽屉 / 桌面端 = 左侧轨道） --- */
.site-nav{
  position:fixed;
  top:0;bottom:0;left:0;
  width:min(86vw,340px);
  z-index:120;
  display:flex;
  flex-direction:column;
  padding:18px 18px 24px;
  background:linear-gradient(180deg,#0B1B2B 0%,#0E2133 55%,#0B1B2B 100%);
  border-right:1px solid var(--line-strong);
  overflow-y:auto;
  transform:translateX(-102%);
  visibility:hidden;
  transition:transform 180ms var(--ease),visibility 180ms var(--ease);
}
.site-nav[data-open="true"]{
  transform:translateX(0);
  visibility:visible;
}

.site-nav > .brand{margin-bottom:18px}

.nav-head{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding-bottom:14px;
  margin-bottom:16px;
  border-bottom:1px solid var(--line);
}

.nav-head__tag{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.22em;
  color:var(--stone);
}

.nav-close{
  display:grid;
  place-items:center;
  width:36px;height:36px;
  border:1px solid var(--line-strong);
  border-radius:2px;
  color:var(--paper);
  font-size:16px;
  line-height:1;
  transition:border-color var(--t) var(--ease),color var(--t) var(--ease);
}
.nav-close:hover,
.nav-close:focus-visible{border-color:var(--flame);color:var(--flame)}

.nav-list{
  display:flex;
  flex-direction:column;
  gap:2px;
}

.nav-item{display:block}

.nav-link{
  display:grid;
  grid-template-columns:auto 1fr;
  align-items:center;
  gap:12px;
  padding:12px 10px;
  border-left:2px solid transparent;
  color:rgba(243,239,230,.86);
  font-size:15px;
  font-weight:500;
  transition:background var(--t) var(--ease),color var(--t) var(--ease),border-color var(--t) var(--ease);
}

.nav-link__idx{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.06em;
  color:var(--stone);
}

.nav-link__text{letter-spacing:.04em}

.nav-link:hover,
.nav-link:focus-visible{
  background:rgba(18,59,46,.9);
  border-left-color:var(--flame);
  color:var(--paper);
}

.nav-link[aria-current="page"]{
  background:rgba(18,59,46,.7);
  border-left-color:var(--signal);
  color:var(--signal);
}
.nav-link[aria-current="page"] .nav-link__idx{color:var(--signal)}

.nav-foot{
  margin-top:auto;
  padding-top:20px;
  border-top:1px solid var(--line);
}

.nav-foot__desc{
  font-size:12px;
  line-height:1.7;
  color:var(--stone);
  margin-bottom:14px;
}

.nav-foot__cta{
  width:100%;
  justify-content:center;
}

/* --- 桌面端：左轨道 --- */
@media (min-width:1024px){
  .site-nav{
    width:var(--rail);
    padding:0;
    align-items:center;
    overflow:hidden;
    transform:none;
    visibility:visible;
    border-right:1px solid var(--line);
    background:linear-gradient(180deg,#0B1B2B 0%,#0F2436 60%,#0B1B2B 100%);
  }

  .site-nav > .brand{
    flex-direction:column;
    gap:8px;
    width:100%;
    margin:0;
    padding:16px 6px 14px;
    border-bottom:1px solid var(--line);
  }
  .site-nav .brand__mark{width:32px;height:32px;font-size:15px}
  .site-nav .brand__name{
    writing-mode:vertical-rl;
    font-size:11px;
    letter-spacing:.24em;
    line-height:1.1;
  }

  .nav-head{
    justify-content:center;
    width:100%;
    padding:10px 0;
    margin:0;
    border-bottom:1px solid var(--line);
  }
  .nav-head__tag{
    writing-mode:vertical-rl;
    font-size:10px;
    letter-spacing:.3em;
    color:var(--stone);
  }
  .nav-close{display:none}

  .nav-list{
    flex:1 1 auto;
    min-height:0;
    gap:0;
    width:100%;
    padding:8px 0;
    overflow-y:auto;
    scrollbar-width:thin;
  }

  .nav-link{
    display:flex;
    flex-direction:column;
    align-items:center;
    gap:3px;
    padding:11px 4px;
    border-left:0;
    border-right:2px solid transparent;
    font-size:12px;
    text-align:center;
    letter-spacing:.02em;
  }
  .nav-link__idx{font-size:10px;letter-spacing:.1em}
  .nav-link:hover,
  .nav-link:focus-visible{
    background:rgba(18,59,46,.85);
    border-left-color:transparent;
    border-right-color:var(--flame);
  }
  .nav-link[aria-current="page"]{
    border-left-color:transparent;
    border-right-color:var(--signal);
    background:rgba(18,59,46,.55);
  }

  .nav-foot{
    width:100%;
    padding:14px 8px 18px;
    margin-top:0;
  }
  .nav-foot__desc{display:none}
  .nav-foot__cta{
    font-size:12px;
    padding:9px 6px;
    letter-spacing:.04em;
  }
}

/* --- 遮罩 --- */
.nav-scrim{
  position:fixed;
  inset:0;
  z-index:110;
  background:rgba(5,11,16,.66);
  opacity:0;
  visibility:hidden;
  pointer-events:none;
  transition:opacity 180ms var(--ease),visibility 180ms var(--ease);
}
.nav-scrim[data-open="true"]{
  opacity:1;
  visibility:visible;
  pointer-events:auto;
}

/* --- 滚动进度（内容地图坐标） --- */
.scroll-meter{
  position:fixed;
  top:var(--bar);
  left:0;right:0;
  height:2px;
  z-index:90;
  pointer-events:none;
  background:rgba(243,239,230,.12);
}
.scroll-meter__bar{
  display:block;
  width:100%;height:100%;
  background:linear-gradient(90deg,var(--signal),var(--flame));
  transform:scaleX(var(--p,0));
  transform-origin:left center;
}

@media (min-width:1024px){
  .scroll-meter{
    top:0;bottom:0;left:var(--rail);right:auto;
    width:2px;height:auto;
  }
  .scroll-meter__bar{
    width:100%;height:100%;
    background:linear-gradient(180deg,var(--signal),var(--flame));
    transform:scaleY(var(--p,0));
    transform-origin:top center;
  }
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer{
  position:relative;
  isolation:isolate;
  background:var(--ink);
  color:var(--paper);
  border-top:1px solid var(--line-strong);
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:0;
  z-index:-1;
  pointer-events:none;
  background-image:repeating-linear-gradient(
    90deg,
    rgba(243,239,230,.045) 0 1px,
    transparent 1px 96px
  );
}

.foot-strip{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  row-gap:4px;
  padding:10px clamp(20px,4vw,40px);
  background:linear-gradient(100deg,var(--field) 0%,#0F3327 55%,var(--field) 100%);
  border-bottom:1px solid var(--line);
  overflow:hidden;
}
.foot-strip__item{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  color:rgba(243,239,230,.62);
  white-space:nowrap;
}
.foot-strip__item:first-child{color:var(--signal)}
.foot-strip__item + .foot-strip__item::before{
  content:"·";
  margin:0 12px;
  color:rgba(138,143,138,.85);
}

.foot-main{
  display:grid;
  grid-template-columns:1fr;
  gap:clamp(28px,4vw,48px);
  max-width:var(--maxw);
  margin-inline:auto;
  padding:clamp(40px,6vw,72px) clamp(20px,4vw,40px);
}
@media (min-width:640px){
  .foot-main{grid-template-columns:1fr 1fr}
  .foot-brand{grid-column:1 / -1}
}
@media (min-width:1024px){
  .foot-main{grid-template-columns:1.5fr .8fr .9fr 1.2fr}
  .foot-brand{grid-column:auto}
}

.foot-brand{display:block}
.foot-brand .brand{margin-bottom:16px}
.foot-brand .btn{margin-top:20px}

.foot-brand__line{
  font-size:clamp(1.05rem,2vw,1.32rem);
  font-weight:800;
  line-height:1.35;
  letter-spacing:.01em;
  max-width:18ch;
}

.foot-summary{
  margin-top:10px;
  max-width:34ch;
  font-size:14px;
  line-height:1.75;
  color:var(--muted);
}

.foot-col__title{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.2em;
  color:var(--stone);
  padding-bottom:10px;
  margin-bottom:14px;
  border-bottom:1px solid var(--line);
}

.foot-links{display:flex;flex-direction:column;gap:2px}

.foot-link{
  display:inline-block;
  font-size:14px;
  color:rgba(243,239,230,.78);
  padding:4px 0;
  border-bottom:1px solid transparent;
  transition:color var(--t) var(--ease),border-color var(--t) var(--ease);
}
.foot-link:hover,
.foot-link:focus-visible{
  color:var(--signal);
  border-bottom-color:rgba(255,210,63,.5);
}

.foot-contact__list{display:grid;gap:14px}
.foot-contact__label{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.2em;
  color:var(--stone);
  margin-bottom:2px;
}
.foot-contact__value{
  font-size:14px;
  line-height:1.7;
  color:var(--paper);
  word-break:break-word;
}
.foot-contact__note{
  margin-top:16px;
  padding-left:12px;
  border-left:2px solid var(--clay);
  font-size:12px;
  line-height:1.75;
  color:var(--muted);
  max-width:34ch;
}

.foot-legal{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px 24px;
  max-width:var(--maxw);
  margin-inline:auto;
  padding:18px clamp(20px,4vw,40px) 28px;
  border-top:1px solid var(--line);
  font-size:12px;
  color:var(--stone);
}
.foot-copy{letter-spacing:.02em}
.foot-year{font-family:var(--font-mono);letter-spacing:.06em;color:rgba(243,239,230,.72)}
.foot-icp{font-family:var(--font-mono);letter-spacing:.06em}
.foot-legal__links{display:flex;flex-wrap:wrap;gap:4px 18px}

/* ============================================================
   SHARED CONTENT PRIMITIVES
   ============================================================ */
.wrap{
  width:100%;
  max-width:var(--maxw);
  margin-inline:auto;
  padding-inline:clamp(20px,4vw,40px);
}

.band{padding-block:clamp(48px,7vw,96px)}
.band--ink{background:var(--ink);color:var(--paper)}
.band--field{background:var(--field);color:var(--paper)}
.band--paper{
  background:var(--paper);
  color:var(--black);
  --muted:rgba(5,11,16,.66);
  --line:rgba(5,11,16,.16);
  --line-strong:rgba(5,11,16,.3);
  --line-dark:rgba(5,11,16,.2);
  --stone:#6E736E;
}

.kicker{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--flame);
}

.idx{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--stone);
  font-variant-numeric:tabular-nums;
}

.mono{
  font-family:var(--font-mono);
  letter-spacing:.04em;
  font-variant-numeric:tabular-nums;
}

.display{
  font-size:clamp(2.6rem,6.5vw,6.8rem);
  font-weight:800;
  line-height:.95;
  letter-spacing:-.03em;
}

.h2{
  font-size:clamp(1.6rem,3.2vw,2.6rem);
  font-weight:800;
  line-height:1.12;
  letter-spacing:-.01em;
}

.lede{
  max-width:56ch;
  font-size:clamp(1rem,1.3vw,1.15rem);
  line-height:1.7;
  color:var(--muted);
}

.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  justify-content:space-between;
  gap:12px 24px;
  padding-bottom:18px;
  margin-bottom:clamp(24px,4vw,40px);
  border-bottom:1px solid var(--line);
}
.section-head__title{
  font-size:clamp(1.4rem,2.6vw,2.2rem);
  font-weight:800;
  line-height:1.15;
  letter-spacing:-.01em;
}
.section-head__note{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--stone);
}

.rule{
  border:0;
  height:1px;
  background:var(--line);
  margin-block:clamp(24px,4vw,48px);
}

/* --- buttons --- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 22px;
  font-size:14px;
  font-weight:700;
  line-height:1.3;
  letter-spacing:.02em;
  border:1px solid transparent;
  border-radius:2px;
  transition:background var(--t) var(--ease),
             color var(--t) var(--ease),
             border-color var(--t) var(--ease);
}
.btn--flame{background:var(--flame);color:var(--black)}
.btn--flame:hover,
.btn--flame:focus-visible{background:var(--signal);color:var(--black)}
.btn--ghost{border-color:var(--line-strong);color:var(--paper)}
.btn--ghost:hover,
.btn--ghost:focus-visible{border-color:var(--flame);color:var(--flame)}
.btn--ink{background:var(--black);color:var(--paper)}
.btn--ink:hover,
.btn--ink:focus-visible{background:var(--field);color:var(--paper)}

/* --- tags & chips --- */
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 8px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  line-height:1.6;
  border:1px solid var(--line-strong);
  border-radius:2px;
  color:var(--muted);
}
.tag--signal{color:var(--signal);border-color:rgba(255,210,63,.48)}
.tag--clay{color:var(--clay);border-color:rgba(184,107,75,.5)}

.chip{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:7px 14px;
  font-size:13px;
  line-height:1.4;
  color:var(--muted);
  border:1px solid var(--line-strong);
  border-radius:2px;
  background:transparent;
  transition:background var(--t) var(--ease),
             color var(--t) var(--ease),
             border-color var(--t) var(--ease);
}
.chip:hover,
.chip:focus-visible{border-color:var(--flame);color:var(--paper)}
.chip[aria-pressed="true"]{
  background:var(--signal);
  border-color:var(--signal);
  color:var(--black);
  font-weight:700;
}

/* --- breadcrumb --- */
.crumb{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  color:var(--stone);
  padding-block:14px;
}
.crumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:8px}
.crumb__item{display:inline-flex;align-items:center;gap:8px}
.crumb__link{
  color:rgba(243,239,230,.8);
  border-bottom:1px solid transparent;
  transition:color var(--t) var(--ease),border-color var(--t) var(--ease);
}
.crumb__link:hover,
.crumb__link:focus-visible{color:var(--signal);border-bottom-color:rgba(255,210,63,.55)}
.crumb__sep{color:rgba(138,143,138,.75)}
.band--paper .crumb__link{color:rgba(5,11,16,.7)}
.band--paper .crumb__link:hover,
.band--paper .crumb__link:focus-visible{color:var(--clay);border-bottom-color:var(--clay)}

/* --- prose --- */
.prose{
  max-width:68ch;
  font-size:clamp(1rem,1.1vw,1.0625rem);
  line-height:1.85;
}
.prose > * + *{margin-top:1em}
.prose h2{
  font-size:1.35rem;
  font-weight:800;
  line-height:1.3;
  margin-top:1.9em;
  padding-bottom:.4em;
  border-bottom:1px solid var(--line);
}
.prose h3{font-size:1.08rem;font-weight:700;margin-top:1.6em}
.prose ul,.prose ol{padding-left:0}
.prose li{
  position:relative;
  padding-left:20px;
  margin-top:.55em;
}
.prose li::before{
  content:"—";
  position:absolute;
  left:0;
  color:var(--flame);
  font-family:var(--font-mono);
}
.prose a{
  color:var(--clay);
  border-bottom:1px solid currentColor;
  transition:color var(--t) var(--ease);
}
.prose a:hover,
.prose a:focus-visible{color:var(--flame)}
.prose strong{font-weight:700}

/* --- grids --- */
.grid{display:grid;gap:clamp(16px,2.5vw,28px)}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(min(100%,280px),1fr))}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(min(100%,230px),1fr))}
.grid--split{grid-template-columns:1fr}
@media (min-width:900px){
  .grid--split{grid-template-columns:7fr 5fr;align-items:start}
}

/* --- figure / 图片容器基础规则 --- */
.figure{
  position:relative;
  margin:0;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:2px;
  background:var(--field);
  box-shadow:var(--shadow-soft);
}
.figure__media{
  display:block;
  width:100%;
  aspect-ratio:16 / 10;
  object-fit:cover;
  object-position:center;
  transition:transform var(--t) var(--ease);
}
.figure:hover .figure__media{transform:scale(1.02)}
.figure--wide .figure__media{aspect-ratio:21 / 9}
.figure__cap{
  padding:10px 14px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.06em;
  line-height:1.7;
  color:var(--stone);
  border-top:1px solid var(--line);
  background:rgba(5,11,16,.32);
}
.band--paper .figure{
  background:#E4DFD2;
  border-color:var(--line);
  box-shadow:none;
}
.band--paper .figure__cap{
  background:rgba(5,11,16,.05);
  color:#6E736E;
  border-top-color:rgba(5,11,16,.14);
}

/* ============================================================
   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;
  }
  .figure:hover .figure__media{transform:none}
  .skip-link{transition:none}
}