/* ==========================================================================
   anbo site kit · shared layer (/assets/site.css)
   01 reset · 02 tokens · 03 typography · 04 layout · 05 header · 06 footer
   07 buttons & tags · 08 components · 09 media · 10 motion · 11 responsive
   ========================================================================== */

/* 01 reset */
*,
*::before,
*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
@media (prefers-reduced-motion:no-preference){html{scroll-behavior:smooth}}
body{margin:0}
h1,h2,h3,h4,h5,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,svg{display:block;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}
::selection{background:var(--anbo-red);color:#fff}

/* 02 tokens */
:root{
  --anbo-red:#C8102E;
  --carbon:#1A1A1A;
  --ink:#0E0E0E;
  --paper:#F4F1EC;
  --pure:#FFFFFF;
  --amber:#FFB81C;
  --amber-deep:#E2A110;
  --steel:#5B7C99;
  --neutral:#666B73;
  --green:#1F7A5A;
  --glass:rgba(255,255,255,0.08);
  --glass-line:rgba(255,255,255,0.16);
  --hair:rgba(26,26,26,0.14);
  --hair-light:rgba(244,241,236,0.14);
  --maxw:1280px;
  --gutter:24px;
  --rail:220px;
  --shadow-glass:0 24px 48px rgba(14,14,14,0.24);
  --font-display:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei","Source Han Sans SC",system-ui,sans-serif;
  --font-body:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular","SF Mono",Consolas,"Liberation Mono",monospace;
}

/* 03 typography */
body{
  background:var(--paper);
  color:var(--carbon);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:900;line-height:1.1;letter-spacing:-0.01em;color:var(--carbon)}
h1{font-size:clamp(40px,5.4vw,72px);line-height:1.05}
h2{font-size:clamp(26px,3.2vw,28px)}
h3{font-size:17px;font-weight:700;line-height:1.5;letter-spacing:0}
.data-num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;font-weight:700;letter-spacing:-0.01em}
.prose{max-width:66ch;color:var(--carbon)}
.prose p + p{margin-top:16px}
.prose a{text-decoration:underline;text-decoration-thickness:2px;text-underline-offset:3px;text-decoration-color:var(--anbo-red)}
.prose strong{font-weight:700}

/* 04 layout */
.container{width:100%;max-width:var(--maxw);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-block:72px}
.section__rule{height:8px;border:0;margin:0;background:var(--anbo-red)}
.grid{display:grid;gap:var(--gutter)}
.grid--8-4{grid-template-columns:minmax(0,2fr) minmax(0,1fr)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}

.chapter{position:relative;padding-top:22px;border-top:1px solid var(--hair)}
.chapter__num{display:block;font-family:var(--font-mono);font-size:13px;font-weight:700;letter-spacing:0.18em;color:var(--anbo-red)}
.chapter__title{margin-top:8px;font-size:clamp(26px,3.2vw,36px)}
.eyebrow{display:inline-block;font-size:12px;font-weight:700;letter-spacing:0.24em;color:var(--anbo-red)}
.lede{max-width:62ch;font-size:17px;line-height:1.8;color:var(--neutral)}
.annotation{font-size:12px;letter-spacing:0.2em;color:var(--neutral)}
.annotation--vertical{writing-mode:vertical-rl;text-orientation:mixed;letter-spacing:0.28em}

.breadcrumb{display:flex;flex-wrap:wrap;align-items:center;gap:6px;padding-block:20px;font-size:12px;letter-spacing:0.12em;color:var(--neutral)}
.breadcrumb__item{display:inline-flex;align-items:center;gap:6px}
.breadcrumb__item + .breadcrumb__item::before{content:"/";color:rgba(102,107,115,0.55)}
.breadcrumb a:hover{color:var(--anbo-red)}
.breadcrumb [aria-current="page"]{color:var(--carbon);font-weight:700}

.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}

/* 05 header */
.skip-link{
  position:fixed;top:12px;left:12px;z-index:120;
  padding:10px 16px;background:var(--amber);color:var(--ink);
  font-size:14px;font-weight:700;border-radius:2px;
  transform:translateY(-200%);transition:transform .18s ease;
}
.skip-link:focus-visible,.skip-link:focus{transform:translateY(0);outline:2px solid var(--purple,var(--paper));outline-offset:2px}

.masthead{
  position:sticky;top:0;z-index:60;
  background:var(--ink);color:var(--paper);
  border-bottom:1px solid var(--hair-light);
}
.masthead::before{
  content:"";display:block;height:4px;
  background:var(--anbo-red);
  box-shadow:inset 120px 0 0 var(--amber);
}
.masthead__inner{
  position:relative;
  display:flex;flex-wrap:wrap;align-items:center;gap:12px;
  max-width:var(--maxw);margin-inline:auto;
  padding:10px var(--gutter);min-height:64px;
}

.masthead__brand{display:flex;align-items:center;gap:12px;flex:0 0 auto;min-width:0}
.masthead__mark{
  display:grid;place-items:center;flex:0 0 auto;
  width:38px;height:42px;
  background:var(--anbo-red);color:var(--pure);
  font-family:var(--font-display);font-weight:900;font-size:19px;line-height:1;
  clip-path:polygon(50% 0,100% 15%,100% 63%,50% 100%,0 63%,0 15%);
}
.masthead__wordmark{display:flex;flex-direction:column;gap:2px;min-width:0}
.masthead__brandline{
  font-size:12px;font-weight:700;letter-spacing:0.02em;
  color:var(--paper);white-space:nowrap;line-height:1.25;
}
.masthead__tagline{
  font-size:10px;letter-spacing:0.26em;line-height:1.25;
  color:var(--amber);white-space:nowrap;
}

.masthead__nav{
  position:absolute;left:0;right:0;top:100%;z-index:5;
  background:var(--ink);
  border-top:1px solid var(--hair-light);
  border-bottom:3px solid var(--anbo-red);
  max-height:0;overflow:hidden;visibility:hidden;
  transition:max-height .3s ease,visibility .3s ease;
}
.masthead__nav[data-open]{
  max-height:min(80vh,520px);overflow-y:auto;visibility:visible;
}
.nav__list{display:flex;flex-direction:column;padding:6px 0 14px}
.nav__item{border-bottom:1px solid rgba(244,241,236,0.08)}
.nav__item:last-child{border-bottom:0}
.nav__link{
  position:relative;display:flex;align-items:center;gap:10px;
  padding:14px var(--gutter);
  font-size:15.5px;font-weight:500;color:rgba(244,241,236,0.8);
  transition:color .18s ease,background-color .18s ease,box-shadow .18s ease;
}
.nav__link::after{
  content:"";position:absolute;left:var(--gutter);right:var(--gutter);bottom:6px;height:2px;
  background:var(--anbo-red);transform:scaleX(0);transform-origin:0 50%;
  transition:transform .22s ease;
}
.nav__link:hover,.nav__link:focus-visible{color:var(--pure)}
.nav__link[aria-current="page"]{
  color:var(--pure);font-weight:700;
  box-shadow:inset 3px 0 0 var(--anbo-red);
  background:rgba(255,255,255,0.04);
}
.nav__link--verify::before{
  content:"";flex:0 0 auto;width:13px;height:15px;
  background:currentColor;opacity:.85;
  clip-path:polygon(50% 0,100% 16%,100% 62%,50% 100%,0 62%,0 16%);
  transition:background-color .18s ease,opacity .18s ease;
}
.nav__link--verify:hover::before,
.nav__link--verify[aria-current="page"]::before{background:var(--amber);opacity:1}

.masthead__actions{display:flex;align-items:center;gap:10px;margin-left:auto}
.masthead__cta{display:none;padding:9px 16px;font-size:13px}

.nav-toggle{
  display:inline-flex;flex-direction:column;justify-content:center;gap:5px;
  width:44px;height:44px;padding:0 11px;
  background:transparent;border:1px solid rgba(244,241,236,0.28);border-radius:2px;
  cursor:pointer;transition:border-color .18s ease,background-color .18s ease;
}
.nav-toggle:hover{border-color:var(--amber)}
.nav-toggle:focus-visible{outline:2px solid var(--amber);outline-offset:2px}
.nav-toggle__bar{display:block;height:2px;width:100%;background:var(--paper);transition:transform .2s ease,opacity .2s ease}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* 06 footer */
.site-footer{
  position:relative;
  background:var(--ink);color:rgba(244,241,236,0.74);
  border-top:4px solid var(--anbo-red);
}
.site-footer::before{
  content:"";position:absolute;left:0;right:0;top:0;height:10px;
  background:repeating-linear-gradient(90deg,rgba(244,241,236,0.24) 0 1px,transparent 1px 16px);
  opacity:.55;pointer-events:none;
}
.footer__inner{max-width:var(--maxw);margin-inline:auto;padding:64px var(--gutter) 28px}
.footer__grid{display:grid;grid-template-columns:1fr;gap:32px 24px}

.footer__brand-name{
  font-family:var(--font-display);font-weight:900;font-size:28px;line-height:1.1;
  color:var(--paper);letter-spacing:-0.01em;
}
.footer__brand-line{margin-top:8px;font-size:13.5px;color:rgba(244,241,236,0.66)}
.footer__tagline{
  display:inline-block;margin-top:12px;padding-top:10px;
  border-top:2px solid var(--anbo-red);
  font-size:11px;letter-spacing:0.26em;color:var(--amber);
}

.footer__col-title{
  display:flex;align-items:center;gap:10px;
  font-family:var(--font-body);font-size:12px;font-weight:700;
  letter-spacing:0.22em;color:var(--paper);
  margin-bottom:16px;
}
.footer__col-title::before{content:"";width:14px;height:2px;background:var(--anbo-red)}
.footer__list{display:flex;flex-direction:column;gap:10px}
.footer__link{
  font-size:14.5px;color:rgba(244,241,236,0.7);
  transition:color .18s ease,box-shadow .18s ease;
}
.footer__link:hover,.footer__link:focus-visible{
  color:var(--pure);
  box-shadow:inset 0 -1px 0 var(--anbo-red);
}
.footer__link:focus-visible{outline:2px solid var(--amber);outline-offset:3px}

.footer__contact-row{display:flex;flex-direction:column;gap:2px;font-size:14px}
.footer__contact-label{font-size:11px;letter-spacing:0.2em;color:rgba(244,241,236,0.42)}
.footer__contact-value{color:rgba(244,241,236,0.86);word-break:break-word;line-height:1.55}
.footer__contact-link{
  display:inline-block;margin-top:16px;
  padding-bottom:2px;font-size:13.5px;font-weight:700;color:var(--amber);
  box-shadow:inset 0 -2px 0 rgba(255,184,28,0.4);
  transition:box-shadow .18s ease;
}
.footer__contact-link:hover{box-shadow:inset 0 -2px 0 var(--amber)}
.footer__contact-link:focus-visible{outline:2px solid var(--amber);outline-offset:3px}

.footer__baseline{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 24px;
  margin-top:48px;padding-top:20px;
  border-top:1px solid var(--hair-light);
}
.footer__legal{font-size:12.5px;letter-spacing:0.04em;color:rgba(244,241,236,0.5)}
.footer__icp{font-family:var(--font-mono);font-size:12px;color:rgba(244,241,236,0.62)}
.footer__policy-links{display:flex;flex-wrap:wrap;gap:8px 20px}
.footer__policy-links .footer__link{font-size:12.5px;color:rgba(244,241,236,0.55)}

/* 07 buttons & tags */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:12px 20px;border:1px solid transparent;border-radius:2px;
  font-family:var(--font-body);font-size:14px;font-weight:700;letter-spacing:0.02em;
  text-align:center;cursor:pointer;
  transition:background-color .18s ease,color .18s ease,border-color .18s ease,transform .18s ease;
}
.btn:focus-visible{outline:2px solid var(--amber);outline-offset:2px}
.btn--primary{background:var(--amber);color:var(--ink);border-color:var(--amber)}
.btn--primary:hover{background:var(--amber-deep);border-color:var(--amber-deep)}
.btn--primary:focus-visible{outline-color:var(--carbon)}
.btn--red{background:var(--anbo-red);color:var(--pure);border-color:var(--anbo-red)}
.btn--red:hover{background:#a90c26;border-color:#a90c26}
.btn--ghost{background:transparent;color:var(--carbon);border-color:rgba(26,26,26,0.28)}
.btn--ghost:hover{border-color:var(--anbo-red);color:var(--anbo-red)}
.btn--block{display:flex;width:100%}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 10px;border:1px solid var(--hair);border-radius:2px;
  font-size:11.5px;font-weight:700;letter-spacing:0.14em;color:var(--neutral);
  background:var(--pure);
}
.tag::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--anbo-red)}

/* 08 components */
.glass{
  background:var(--glass);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  border:1px solid var(--glass-line);
  color:var(--paper);
  box-shadow:var(--shadow-glass);
}

.tabs{display:block}
.tabs__list{
  display:flex;flex-wrap:wrap;gap:2px;
  border-bottom:1px solid rgba(26,26,26,0.16);
  margin-bottom:24px;
}
.tabs__btn{
  appearance:none;background:transparent;border:0;
  border-bottom:2px solid transparent;margin-bottom:-1px;
  padding:12px 18px;font-size:14px;font-weight:700;letter-spacing:0.04em;
  color:var(--neutral);cursor:pointer;
  transition:color .18s ease,border-color .2s ease;
}
.tabs__btn:hover{color:var(--carbon)}
.tabs__btn[aria-selected="true"]{color:var(--carbon);border-bottom-color:var(--anbo-red)}
.tabs__btn:focus-visible{outline:2px solid var(--amber);outline-offset:-2px}
.tabs__panel{padding-block:6px;animation:tabs-fade .18s ease both}
.tabs__panel[hidden]{display:none}
@keyframes tabs-fade{from{opacity:0}to{opacity:1}}

/* 09 media */
.media{
  position:relative;display:block;overflow:hidden;
  background:var(--carbon);
  border:1px solid var(--hair);
}
.media__img{width:100%;height:100%;object-fit:cover;display:block}
.media--wide{aspect-ratio:16/9}
.media--square{aspect-ratio:1/1}
.media--tall{aspect-ratio:3/4}
.media--placeholder{
  background-image:repeating-linear-gradient(135deg,rgba(255,255,255,0.07) 0 1px,transparent 1px 14px);
}
.media__caption{
  position:absolute;left:0;bottom:0;
  padding:8px 12px;
  background:var(--glass);
  -webkit-backdrop-filter:blur(8px);
  backdrop-filter:blur(8px);
  border-top-right-radius:2px;
  color:var(--paper);
  font-size:12px;letter-spacing:0.14em;
}
.media-figure{display:flex;flex-direction:column;gap:10px}
.media-figure figcaption{font-size:12px;letter-spacing:0.12em;color:var(--neutral)}

/* 10 motion */
[data-reveal]{transition:opacity .5s ease,transform .5s ease}
.has-js [data-reveal]{opacity:0;transform:translateY(12px)}
.has-js [data-reveal].is-revealed{opacity:1;transform:none}

.scroll-progress{
  position:fixed;top:0;left:0;z-index:90;
  width:100%;height:3px;
  background:var(--amber);
  transform:scaleX(0);transform-origin:0 50%;
  pointer-events:none;opacity:.95;
}
.to-top{
  position:fixed;right:20px;bottom:20px;z-index:70;
  display:inline-flex;align-items:center;justify-content:center;
  width:46px;height:46px;padding:0;
  border:1px solid var(--anbo-red);border-radius:2px;
  background:var(--amber);color:var(--ink);
  cursor:pointer;
  opacity:0;transform:translateY(8px);pointer-events:none;
  box-shadow:0 14px 28px rgba(14,14,14,0.28);
  transition:opacity .18s ease,transform .18s ease;
}
.to-top::before{
  content:"";width:10px;height:10px;
  border-left:2px solid currentColor;border-top:2px solid currentColor;
  transform:rotate(45deg) translate(1px,1px);
}
.to-top[data-visible]{opacity:1;transform:none;pointer-events:auto}
.to-top:focus-visible{outline:2px solid var(--carbon);outline-offset:2px}

/* 11 responsive */
@media (min-width:640px){
  .masthead__brandline{font-size:13px}
  .masthead__tagline{font-size:10.5px}
  .footer__grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__brand{grid-column:1 / -1}
}
@media (min-width:900px){
  .section{padding-block:96px}
  .masthead__cta{display:inline-flex}
  .footer__grid{grid-template-columns:1.3fr 0.9fr 0.9fr 0.8fr 1.4fr}
  .footer__brand{grid-column:auto}
}
@media (min-width:1024px){
  .masthead__inner{flex-wrap:nowrap;gap:24px;min-height:76px;padding-block:0}
  .nav-toggle{display:none}
  .masthead__nav{
    position:static;margin-left:auto;
    max-height:none;overflow:visible;visibility:visible;
    background:none;border:0;
  }
  .nav__list{flex-direction:row;align-items:center;gap:2px;padding:0}
  .nav__item{border-bottom:0}
  .nav__link{
    padding:10px 12px;font-size:14px;
    box-shadow:none;background:none;
  }
  .nav__link::after{display:block}
  .nav__link[aria-current="page"]{
    box-shadow:none;background:none;
  }
  .nav__link:hover::after,
  .nav__link:focus-visible::after,
  .nav__link[aria-current="page"]::after{transform:scaleX(1)}
  .masthead__actions{margin-left:8px}
}
@media (max-width:899px){
  .grid--8-4{grid-template-columns:minmax(0,1fr)}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:619px){
  :root{--gutter:18px}
  body{font-size:16px}
  .grid--2,.grid--3{grid-template-columns:minmax(0,1fr)}
  .footer__inner{padding-top:48px}
  .to-top{right:14px;bottom:14px}
}
@media (prefers-reduced-motion:reduce){
  *,
  *::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}
  .to-top{transform:none}
}