/* ============================================================
   OB SPORT — shared site kit
   1. reset  2. tokens  3. base typography  4. header
   5. footer  6. shared components  7. motion  8. responsive
   ============================================================ */

/* ---------- 1. reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd,fieldset{margin:0;padding:0}
ul,ol{list-style:none}
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%}
:where(a,button,[tabindex],summary):focus-visible{outline:2px solid var(--amber);outline-offset:3px;border-radius:1px}

/* ---------- 2. tokens ---------- */
:root{
  --ink-900:#020811;
  --ink-800:#06101D;
  --ink-750:#0A1625;
  --panel:#172635;
  --line:#2E4257;
  --white:#F2F7FB;
  --muted:#9AAAB8;
  --cyan:#2EF2D8;
  --amber:#FFB24A;
  --coral:#FF6F61;
  --mint:#7CE3A4;

  --rail-w:108px;
  --strip-h:44px;
  --topbar-h:58px;
  --strip-h-sm:30px;
  --shell-max:1240px;
  --gutter:clamp(16px,4vw,56px);
  --gap:clamp(14px,2vw,24px);

  --shadow-hard:6px 6px 0 0 rgba(46,66,87,.85);
  --shadow-soft:4px 4px 0 0 rgba(46,66,87,.55);
  --ease:cubic-bezier(.22,.68,.28,1);

  --font-display:"Oswald","Barlow Condensed","Noto Sans SC","HarmonyOS Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-body:"Noto Sans SC","HarmonyOS Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
}

/* ---------- 3. base ---------- */
body{
  min-height:100vh;
  background-color:var(--ink-800);
  background-image:
    linear-gradient(to right, rgba(46,66,87,.22) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(46,66,87,.14) 1px, transparent 1px);
  background-size:96px 96px;
  color:var(--white);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
  padding-top:calc(var(--topbar-h) + var(--strip-h-sm));
}
body.nav-open{overflow:hidden}

h1,h2,h3,h4{font-family:var(--font-display);font-weight:700;line-height:1.1;letter-spacing:-.01em;color:var(--white)}
h1{font-size:clamp(2.25rem,6vw,4.5rem);letter-spacing:-.02em;line-height:1.02}
h2{font-size:clamp(1.5rem,3.4vw,2.75rem)}
h3{font-size:clamp(1.125rem,2vw,1.5rem);letter-spacing:0;line-height:1.25}
h4{font-size:1rem;letter-spacing:.01em}
strong,b{font-weight:700}

.wrap{width:100%;max-width:var(--shell-max);margin-inline:auto;padding-inline:var(--gutter)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}

.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.06em}
.kicker{display:inline-flex;align-items:center;gap:.55rem;font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.24em;text-transform:uppercase;color:var(--cyan)}
.kicker::before{content:"";width:18px;height:1px;background:var(--cyan);flex:0 0 auto}
.lede{font-size:clamp(1rem,1.5vw,1.1875rem);line-height:1.8;color:var(--muted);max-width:60ch}
.display-1{font-family:var(--font-display);font-weight:700;font-size:clamp(2.5rem,7vw,5.5rem);line-height:.98;letter-spacing:-.03em}
.display-2{font-family:var(--font-display);font-weight:700;font-size:clamp(1.75rem,4vw,3rem);line-height:1.06;letter-spacing:-.02em}
.prose{max-width:68ch;line-height:1.8}
.prose p+p{margin-top:1em}
.prose strong{color:var(--cyan)}
.prose h3{margin-top:1.6em;margin-bottom:.5em}

/* ---------- 4. header ---------- */
.site-header{position:relative;z-index:80}
.skip-link{
  position:fixed;top:8px;left:8px;z-index:200;
  transform:translateY(-180%);
  padding:.65rem 1rem;background:var(--cyan);color:var(--ink-900);
  font-family:var(--font-mono);font-size:.75rem;letter-spacing:.12em;font-weight:700;
  transition:transform .2s var(--ease);
}
.skip-link:focus{transform:translateY(0)}

/* 顶栏（移动/平板） */
.rail{
  position:fixed;top:0;left:0;right:0;z-index:85;
  display:flex;align-items:center;gap:12px;
  height:var(--topbar-h);padding:0 14px;
  background:rgba(2,8,17,.97);
  border-bottom:1px solid var(--line);
}
.brand{display:flex;align-items:center;gap:10px;min-width:0;color:var(--white)}
.brand__mark{
  display:grid;place-items:center;flex:0 0 auto;
  width:34px;height:34px;
  border:2px solid var(--cyan);color:var(--cyan);
  font-family:var(--font-mono);font-size:.75rem;font-weight:700;letter-spacing:.02em;
  box-shadow:3px 3px 0 0 rgba(46,242,216,.22);
}
.brand__lockup{display:flex;flex-direction:column;line-height:1.15;min-width:0}
.brand__latin{font-family:var(--font-mono);font-size:.5625rem;letter-spacing:.22em;color:var(--muted)}
.brand__cn{font-family:var(--font-display);font-size:.9375rem;font-weight:700;letter-spacing:.02em;white-space:nowrap}
.rail__tagline{display:none}

.nav-toggle{
  display:inline-flex;align-items:center;gap:8px;margin-left:auto;
  padding:8px 10px;border:1px solid var(--line);background:var(--panel);color:var(--white);
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.16em;text-transform:uppercase;
  transition:border-color .18s,color .18s;
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle__icon{display:grid;gap:4px;width:16px}
.nav-toggle__icon span{display:block;height:2px;background:currentColor;transition:transform .24s var(--ease),opacity .24s}
.site-header[data-open] .nav-toggle__icon span:first-child{transform:translateY(3px) rotate(45deg)}
.site-header[data-open] .nav-toggle__icon span:last-child{transform:translateY(-3px) rotate(-45deg)}
.nav-toggle__text{line-height:1}

.rail__badge{display:none}
.rail__dot{width:6px;height:6px;border-radius:50%;background:var(--amber);animation:pulse 2.4s var(--ease) infinite}
.rail__v{font-family:var(--font-mono);font-size:.625rem;letter-spacing:.1em}

/* 导航：移动端为底部抽屉 */
.site-nav{
  position:fixed;left:0;right:0;bottom:0;z-index:90;
  display:flex;flex-direction:column;gap:12px;
  max-height:82dvh;overflow-y:auto;
  padding:16px 16px calc(20px + env(safe-area-inset-bottom,0px));
  background:var(--ink-900);
  border-top:2px solid var(--cyan);
  box-shadow:0 -18px 40px rgba(2,8,17,.72);
  transform:translateY(101%);
  visibility:hidden;
  transition:transform .34s var(--ease),visibility .34s var(--ease);
}
.site-nav[data-open]{transform:translateY(0);visibility:visible}
.site-nav__title{
  display:flex;align-items:center;gap:6px;
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.22em;
  text-transform:uppercase;color:var(--amber);
  padding-bottom:10px;border-bottom:1px solid var(--line);
}
.site-nav__list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}
.site-nav__item{min-width:0}
.site-nav__link{
  display:flex;align-items:center;gap:10px;
  padding:12px;border:1px solid var(--line);background:var(--panel);
  color:var(--white);
  transition:border-color .18s,background-color .18s,color .18s;
}
.site-nav__link:hover,.site-nav__link:focus-visible{border-color:var(--cyan);background:rgba(46,242,216,.08);color:var(--cyan)}
.site-nav__index{font-family:var(--font-mono);font-size:.625rem;letter-spacing:.08em;color:var(--amber)}
.site-nav__label{font-size:.9375rem;font-weight:600;letter-spacing:.02em}
.site-nav__link[aria-current="page"]{border-color:var(--cyan);background:rgba(46,242,216,.1);color:var(--cyan)}
.site-nav__link[aria-current="page"] .site-nav__index{color:var(--cyan)}
.site-nav__foot{display:flex;flex-direction:column;gap:8px;padding-top:12px;border-top:1px solid var(--line)}
.site-nav__hours{font-family:var(--font-mono);font-size:.625rem;letter-spacing:.14em;color:var(--muted)}

/* 状态条 */
.strip{
  position:fixed;top:var(--topbar-h);left:0;right:0;z-index:84;
  display:flex;align-items:center;gap:12px;
  height:var(--strip-h-sm);padding:0 14px;
  background:var(--ink-900);
  border-bottom:1px solid var(--line);
  overflow:hidden;
}
.strip__text{
  display:flex;align-items:center;gap:8px;min-width:0;
  font-family:var(--font-mono);font-size:.5625rem;letter-spacing:.12em;color:var(--muted);
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;
}
.strip__dot{
  flex:0 0 auto;width:6px;height:6px;border-radius:50%;
  background:var(--amber);box-shadow:0 0 0 3px rgba(255,178,74,.16);
  animation:pulse 2.4s var(--ease) infinite;
}
.strip__actions{display:none}
.strip__progress{
  position:absolute;left:0;bottom:0;width:100%;height:2px;
  background:linear-gradient(90deg,var(--cyan),var(--amber));
  transform:scaleX(0);transform-origin:0 50%;
  transition:transform .12s linear;
}

@keyframes pulse{
  0%,100%{opacity:1;transform:scale(1)}
  50%{opacity:.55;transform:scale(.86)}
}

/* ---------- 5. footer ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(48px,8vw,96px);
  background:var(--ink-900);
  border-top:2px solid var(--line);
  overflow:hidden;
}
.site-footer::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:
    linear-gradient(to right, rgba(46,66,87,.2) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(46,66,87,.1) 1px, transparent 1px);
  background-size:96px 96px;
}
.site-footer .wrap{position:relative;z-index:1;padding-block:clamp(32px,5vw,64px) 24px}

.footer-wordmark{
  font-family:var(--font-display);font-weight:700;
  font-size:clamp(2.5rem,13vw,9rem);line-height:.82;letter-spacing:-.02em;
  color:transparent;-webkit-text-stroke:1px rgba(46,66,87,.9);
  white-space:nowrap;overflow:hidden;
  margin-bottom:clamp(24px,4vw,40px);
}
@supports not (-webkit-text-stroke:1px red){
  .footer-wordmark{color:rgba(46,66,87,.5)}
}

.footer-grid{display:grid;grid-template-columns:1fr;gap:clamp(24px,4vw,40px)}
.footer-brand__cn{font-family:var(--font-display);font-size:1.375rem;font-weight:700;letter-spacing:.01em}
.footer-brand__line{font-family:var(--font-mono);font-size:.625rem;letter-spacing:.2em;text-transform:uppercase;color:var(--cyan);margin-top:6px}
.footer-summary{margin-top:12px;font-size:.875rem;line-height:1.75;color:var(--muted);max-width:36ch}
.footer-hours{
  display:flex;align-items:center;gap:8px;margin-top:14px;
  font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.1em;color:var(--white);
}
.footer-hours__dot{width:6px;height:6px;border-radius:50%;background:var(--mint)}

.footer-nav{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
.footer-nav__group{min-width:0}
.footer-nav__title{
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.22em;text-transform:uppercase;
  color:var(--amber);
  padding-bottom:8px;margin-bottom:10px;border-bottom:1px solid var(--line);
}
.footer-nav__list{display:flex;flex-direction:column;gap:6px}
.footer-nav__link{
  display:inline-block;font-size:.875rem;color:var(--muted);
  padding:2px 0;border-bottom:1px solid transparent;
  transition:color .18s,border-color .18s;
}
.footer-nav__link:hover,.footer-nav__link:focus-visible{color:var(--cyan);border-bottom-color:var(--cyan)}

.footer-contact__title{
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.22em;text-transform:uppercase;
  color:var(--amber);
  padding-bottom:8px;margin-bottom:10px;border-bottom:1px solid var(--line);
}
.footer-contact__list{display:flex;flex-direction:column;gap:10px}
.footer-contact__item{display:grid;gap:2px;min-width:0}
.footer-contact__label{font-family:var(--font-mono);font-size:.5625rem;letter-spacing:.2em;text-transform:uppercase;color:var(--muted)}
.footer-contact__value{font-size:.875rem;line-height:1.6;color:var(--white);overflow-wrap:anywhere}
.footer-contact__note{
  margin-top:12px;padding-left:10px;border-left:2px solid var(--line);
  font-size:.75rem;line-height:1.65;color:var(--muted);
}

.footer-base{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:10px 20px;margin-top:clamp(28px,4vw,44px);padding-top:16px;
  border-top:1px solid var(--line);
  font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.08em;color:var(--muted);
}
.footer-icp{color:var(--white)}
.footer-copy{font-variant-numeric:tabular-nums}
.footer-base__legal{
  flex-basis:100%;
  font-family:var(--font-body);font-size:.75rem;letter-spacing:0;line-height:1.6;color:var(--muted);
}

/* ---------- 6. shared components ---------- */
.section{padding-block:clamp(36px,6vw,72px)}
.section__head{
  display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;gap:16px;
  padding-bottom:16px;border-bottom:1px solid var(--line);
  margin-bottom:clamp(20px,3vw,32px);
}
.section__title{margin:0}

.grid-12{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:var(--gap)}
.span-4,.span-5,.span-6,.span-7,.span-8,.span-12{grid-column:1 / -1}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5rem;
  padding:.72rem 1.15rem;
  border:1px solid var(--cyan);background:var(--cyan);color:var(--ink-900);
  font-family:var(--font-mono);font-size:.75rem;font-weight:700;
  letter-spacing:.1em;text-transform:uppercase;white-space:nowrap;
  transition:transform .18s var(--ease),box-shadow .18s var(--ease),background-color .18s,color .18s,border-color .18s;
}
.btn:hover{transform:translate(-1px,-1px);box-shadow:4px 4px 0 0 rgba(46,242,216,.35)}
.btn:active{transform:translate(1px,1px);box-shadow:none}
.btn--primary{background:var(--cyan);border-color:var(--cyan);color:var(--ink-900)}
.btn--ghost{background:transparent;border-color:var(--line);color:var(--white)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan);box-shadow:4px 4px 0 0 rgba(46,66,87,.9)}
.btn--amber{background:var(--amber);border-color:var(--amber);color:var(--ink-900)}
.btn--amber:hover{box-shadow:4px 4px 0 0 rgba(255,178,74,.35)}
.btn--sm{padding:.5rem .8rem;font-size:.6875rem;letter-spacing:.08em}
.btn[disabled],.btn[aria-disabled="true"]{opacity:.45;pointer-events:none}

.panel{
  background:var(--panel);
  border:1px solid var(--line);
  padding:clamp(16px,2.4vw,26px);
}
.panel--raised{border-color:rgba(46,242,216,.28);box-shadow:var(--shadow-hard)}

.tag{
  display:inline-flex;align-items:center;gap:.4rem;
  padding:.28rem .55rem;
  border:1px solid var(--line);background:rgba(23,38,53,.6);
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.14em;text-transform:uppercase;
  color:var(--muted);
}
.tag--cyan{color:var(--cyan);border-color:rgba(46,242,216,.45)}
.tag--amber{color:var(--amber);border-color:rgba(255,178,74,.45)}

.media{
  position:relative;display:block;width:100%;
  aspect-ratio:16 / 9;overflow:hidden;
  background:linear-gradient(135deg,var(--ink-750),var(--ink-800));
  border:1px solid var(--line);
  box-shadow:var(--shadow-hard);
}
.media > img,.media > svg,.media > video,.media > picture > img{width:100%;height:100%;object-fit:cover;display:block}
.media--wide{aspect-ratio:21 / 9}
.media--tall{aspect-ratio:4 / 5}
.media--square{aspect-ratio:1 / 1}
.media__label{
  position:absolute;left:0;bottom:0;
  padding:.4rem .6rem;
  background:var(--ink-900);
  border-top:1px solid var(--line);border-right:1px solid var(--line);
  font-family:var(--font-mono);font-size:.5625rem;letter-spacing:.16em;text-transform:uppercase;
  color:var(--cyan);
}

.data-table{width:100%;font-size:.875rem}
.data-table th,.data-table td{padding:10px 12px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
.data-table thead th{
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.16em;text-transform:uppercase;
  color:var(--muted);background:var(--ink-750);font-weight:500;
}
.data-table tbody tr{transition:background-color .18s}
.data-table tbody tr:hover{background:rgba(46,242,216,.05)}
.data-table td{font-variant-numeric:tabular-nums}
.data-table .num{font-family:var(--font-mono);text-align:right;color:var(--white)}

.stat{
  display:flex;flex-direction:column;gap:4px;
  padding:14px 16px;
  border-left:2px solid var(--cyan);
  background:rgba(23,38,53,.6);
}
.stat__value{font-family:var(--font-mono);font-variant-numeric:tabular-nums;font-size:clamp(1.5rem,3vw,2rem);font-weight:700;line-height:1;color:var(--white)}
.stat__label{font-size:.75rem;letter-spacing:.04em;color:var(--muted)}

.crumbs{font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.1em;color:var(--muted);padding-block:14px}
.crumbs__list{display:flex;flex-wrap:wrap;align-items:center;gap:8px}
.crumbs__item{display:flex;align-items:center;gap:8px}
.crumbs__item+.crumbs__item::before{content:"/";color:var(--line)}
.crumbs__link{border-bottom:1px solid transparent;transition:color .18s,border-color .18s}
.crumbs__link:hover,.crumbs__link:focus-visible{color:var(--cyan);border-bottom-color:var(--cyan)}
.crumbs__current{color:var(--white)}

.rule{height:1px;border:0;background:var(--line);margin-block:clamp(24px,4vw,40px)}
.callout{
  border-left:3px solid var(--amber);
  background:rgba(255,178,74,.07);
  padding:14px 16px;
  font-size:.875rem;line-height:1.7;color:var(--white);
}

/* ---------- 7. motion ---------- */
.has-js [data-reveal]{
  opacity:0;transform:translateY(12px);
  transition:opacity .52s var(--ease),transform .52s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
}
.has-js [data-reveal].is-visible{opacity:1;transform:none}

@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;
  }
  .has-js [data-reveal]{opacity:1;transform:none}
  .strip__dot,.rail__dot{animation:none}
}

/* ---------- 8. responsive ---------- */
@media (min-width:820px){
  .span-4{grid-column:span 4}
  .span-5{grid-column:span 5}
  .span-6{grid-column:span 6}
  .span-7{grid-column:span 7}
  .span-8{grid-column:span 8}
  .span-12{grid-column:span 12}
  .footer-grid{grid-template-columns:minmax(0,1.3fr) minmax(0,1.4fr) minmax(0,1.2fr)}
}

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

  .rail{
    position:fixed;inset:0 auto 0 0;right:auto;
    width:var(--rail-w);height:100dvh;
    flex-direction:column;align-items:center;justify-content:flex-start;
    gap:16px;padding:22px 10px 18px;
    border-right:1px solid var(--line);border-bottom:0;
    overflow-y:auto;scrollbar-width:none;
  }
  .rail::-webkit-scrollbar{display:none}
  .brand{flex-direction:column;gap:10px;text-align:center}
  .brand__mark{width:48px;height:48px;font-size:.875rem;box-shadow:4px 4px 0 0 rgba(46,242,216,.22)}
  .brand__lockup{align-items:center;gap:3px}
  .brand__latin{font-size:.5625rem}
  .brand__cn{font-size:.6875rem;letter-spacing:.04em}
  .rail__tagline{
    display:block;margin-top:-4px;
    font-size:.5625rem;line-height:1.6;letter-spacing:.06em;
    color:var(--muted);text-align:center;
  }
  .nav-toggle{display:none}

  .site-nav{
    position:static;transform:none;visibility:visible;
    max-height:none;overflow:visible;
    width:100%;padding:8px 0 0;
    background:transparent;border-top:1px solid var(--line);
    box-shadow:none;
    transition:none;
  }
  .site-nav__title{display:none}
  .site-nav__list{display:flex;flex-direction:column;gap:2px;width:100%}
  .site-nav__link{
    flex-direction:column;align-items:center;justify-content:center;gap:4px;
    padding:8px 0;border:0;background:transparent;color:var(--muted);
  }
  .site-nav__link:hover,.site-nav__link:focus-visible{background:rgba(46,242,216,.07);color:var(--cyan)}
  .site-nav__label{writing-mode:vertical-rl;text-orientation:mixed;font-size:.75rem;letter-spacing:.16em;line-height:1.15}
  .site-nav__index{font-size:.5rem;letter-spacing:.06em;color:var(--line)}
  .site-nav__link[aria-current="page"]{background:rgba(46,242,216,.08);color:var(--cyan);box-shadow:inset 2px 0 0 0 var(--cyan)}
  .site-nav__link[aria-current="page"] .site-nav__index{color:var(--amber)}
  .site-nav__foot{display:none}

  .rail__badge{
    display:flex;align-items:center;gap:6px;margin-top:auto;
    padding:4px 8px;border:1px solid rgba(255,178,74,.35);color:var(--amber);
  }

  .strip{top:0;left:var(--rail-w);right:0;height:var(--strip-h);padding:0 24px;gap:20px}
  .strip__text{font-size:.625rem;letter-spacing:.14em}
  .strip__actions{display:flex;align-items:center;gap:8px;margin-left:auto}
}

@media (min-width:1440px){
  :root{--rail-w:120px}
  .site-nav__label{font-size:.8125rem}
}