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

/* ===== tokens ===== */
:root{
  --ink-blue:#080A18;
  --plum:#241A54;
  --electric:#3D7BFF;
  --indigo-soft:#6E8CFF;
  --lime:#C6FF3D;
  --wine:#6E1B38;
  --teal:#0D3A3F;
  --paper:#F5F3EC;
  --ink:#101018;
  --grey-violet:#8C8CA6;
  --tag-gold:#E3C46B;

  --font-display:"Noto Sans SC Heavy","HarmonyOS Sans SC Black",system-ui,sans-serif;
  --font-sub:"Noto Sans SC Bold","Noto Sans SC",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,monospace;
  --font-body:"Noto Sans SC Regular","Noto Sans SC",system-ui,sans-serif;

  --wrap:1180px;
  --wrap-narrow:720px;
  --wrap-wide:1440px;
  --gutter:clamp(16px,4vw,48px);
  --header-h:96px;
  --header-h-condensed:64px;
  --radius:2px;
  --shadow-layer:0 2px 0 rgba(8,10,24,.35), 0 10px 24px rgba(8,10,24,.45);
  --hair:1px solid rgba(245,243,236,.16);
}

body{
  background:var(--ink-blue);
  color:var(--paper);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
}

/* 中文标题紧凑粗体 */
h1,h2,h3{font-family:var(--font-display);font-weight:900;letter-spacing:-.03em;line-height:1.06}
h1{font-size:clamp(40px,7vw,104px)}
h2{font-size:clamp(28px,4.4vw,60px)}
h3{font-family:var(--font-sub);font-weight:700;font-size:clamp(20px,2.4vw,30px);letter-spacing:-.01em;line-height:1.24}
strong,b{font-weight:700}

:focus-visible{outline:2px solid var(--electric);outline-offset:3px;box-shadow:0 0 0 4px rgba(198,255,61,.55)}
a:focus-visible,button:focus-visible{outline:2px solid var(--electric);box-shadow:inset 0 0 0 2px var(--lime)}

/* ===== skip link ===== */
.skip-link{
  position:absolute;left:12px;top:-64px;z-index:999;
  background:var(--lime);color:var(--ink);
  font-family:var(--font-mono);font-size:13px;letter-spacing:.08em;
  padding:10px 16px;border-radius:var(--radius);
  transition:top .16s ease;
}
.skip-link:focus{top:12px}

/* ===== containers ===== */
.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding:0 var(--gutter)}
.wrap--wide{max-width:var(--wrap-wide)}
.wrap--narrow{max-width:var(--wrap-narrow)}

/* ===== header ===== */
.site-header{
  position:sticky;top:0;z-index:80;
  background:linear-gradient(180deg,rgba(8,10,24,.96),rgba(8,10,24,.88));
  border-bottom:var(--hair);
  backdrop-filter:blur(6px);
}
.site-header__inner{
  max-width:var(--wrap-wide);margin:0 auto;
  padding:0 var(--gutter);
  min-height:var(--header-h);
  display:grid;
  grid-template-columns:auto 1fr auto;
  align-items:center;
  gap:clamp(12px,2vw,32px);
  transition:min-height .18s ease;
}
.site-header.is-condensed .site-header__inner{min-height:var(--header-h-condensed)}
.site-header.is-condensed .brand__round{opacity:0;pointer-events:none;transform:translateY(-6px)}

.brand{display:flex;flex-direction:column;gap:4px;padding:12px 0}
.brand__name{
  font-family:var(--font-display);font-weight:900;
  font-size:clamp(20px,2.1vw,28px);
  letter-spacing:-.03em;line-height:1;
  color:var(--paper);
}
.brand__name:hover{color:var(--lime)}
.brand__round{
  display:flex;align-items:baseline;gap:6px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;
  color:var(--grey-violet);text-transform:uppercase;
  transition:opacity .18s ease,transform .18s ease;
}
.brand__round-num{font-size:14px;color:var(--lime);font-weight:600}

.header-pulse{
  align-self:center;height:1px;width:100%;
  background:linear-gradient(90deg,transparent,rgba(61,123,255,.9) 18%,rgba(198,255,61,.85) 50%,rgba(61,123,255,.9) 82%,transparent);
  background-size:220% 100%;
  animation:pulse-line 3.6s linear infinite;
}
@keyframes pulse-line{from{background-position:0% 0}to{background-position:-220% 0}}

.nav-index{display:flex;align-items:center;justify-content:flex-end}
.nav-index__list{display:flex;align-items:center;gap:clamp(8px,1.4vw,20px)}
.nav-index__link{
  display:inline-block;
  font-family:var(--font-body);font-size:12px;font-weight:500;
  letter-spacing:.16em;
  color:var(--grey-violet);
  padding:8px 4px;
  border-bottom:1px solid transparent;
  transition:color .16s ease,border-color .16s ease;
}
.nav-index__link:hover{color:var(--paper);border-bottom-color:var(--lime)}
.nav-index__link[aria-current="page"]{color:var(--lime);border-bottom-color:var(--lime)}

.nav-toggle{display:none;align-items:center;gap:8px;padding:10px 12px;border:1px solid rgba(245,243,236,.22);border-radius:var(--radius)}
.nav-toggle__bars{display:flex;flex-direction:column;gap:4px;width:18px}
.nav-toggle__bars i{display:block;height:2px;background:var(--lime);transition:transform .16s ease,opacity .16s ease}
.nav-toggle__text{font-family:var(--font-mono);font-size:12px;letter-spacing:.14em;color:var(--paper)}

/* ===== buttons / tags ===== */
.btn{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-body);font-weight:700;font-size:15px;letter-spacing:.02em;
  padding:12px 22px;border-radius:var(--radius);
  border:1px solid transparent;
  transition:transform .16s ease,box-shadow .16s ease,background-color .16s ease,color .16s ease,border-color .16s ease;
}
.btn--primary{background:linear-gradient(120deg,var(--electric),#7A4BFF);color:#fff;box-shadow:var(--shadow-layer)}
.btn--primary:hover{transform:translateY(-2px);box-shadow:0 4px 0 rgba(8,10,24,.4),0 14px 28px rgba(61,123,255,.35)}
.btn--ghost{border-color:rgba(245,243,236,.28);color:var(--paper)}
.btn--ghost:hover{border-color:var(--lime);color:var(--lime)}
.btn--tag{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.16em;text-transform:uppercase;
  border:1px solid var(--tag-gold);color:var(--tag-gold);
  padding:8px 14px;background:rgba(227,196,107,.06);
}
.btn--tag:hover{background:var(--tag-gold);color:var(--ink)}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  font-family:var(--font-mono);font-size:12px;font-weight:600;letter-spacing:.14em;
  padding:4px 10px;border-radius:var(--radius);
  border:1px solid rgba(245,243,236,.3);color:var(--paper);
  background:rgba(8,10,24,.4);
}
.tag--gold{border-color:var(--tag-gold);color:var(--tag-gold)}
.tag--green{border-color:var(--lime);color:var(--lime)}
.tag--blue{border-color:var(--electric);color:var(--indigo-soft)}

/* ===== breadcrumb ===== */
.breadcrumb{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:13px;letter-spacing:.1em;color:var(--grey-violet);font-family:var(--font-mono)}
.breadcrumb__item{display:inline-flex;align-items:center;gap:8px}
.breadcrumb__item:not(:last-child)::after{content:"/";color:rgba(140,140,166,.6)}
.breadcrumb__item a:hover{color:var(--lime)}
.breadcrumb__item [aria-current="page"]{color:var(--paper)}

/* ===== sections & plates ===== */
.section{padding:clamp(48px,7vw,112px) 0}
.section--plate{position:relative}
.plate{position:relative;background:var(--plum);border:var(--hair);border-radius:var(--radius)}
.plate--plum{background:linear-gradient(135deg,var(--plum) 0%,#1A123E 60%,var(--ink-blue) 100%)}
.plate--wine{background:linear-gradient(135deg,var(--wine) 0%,#4A1230 70%,var(--ink-blue) 100%)}
.plate--teal{background:linear-gradient(135deg,var(--teal) 0%,#0A2A31 65%,var(--ink-blue) 100%)}
.plate--cut{
  clip-path:polygon(0 0,100% 0,100% 78%,0 100%);
  padding-bottom:clamp(56px,8vw,132px);
}

/* ===== paper ===== */
.paper{
  background:var(--paper);color:var(--ink);
  border:1px solid rgba(16,16,24,.12);
  border-radius:var(--radius);
  box-shadow:0 2px 0 rgba(8,10,24,.3),0 18px 40px rgba(8,10,24,.5);
  padding:clamp(24px,4vw,56px);
}
.paper--card{padding:clamp(18px,2.4vw,32px)}
.paper h2,.paper h3{color:var(--ink)}
.paper a{color:#1B3FA8;border-bottom:1px solid rgba(27,63,168,.4)}
.paper a:hover{color:var(--wine);border-bottom-color:var(--wine)}

/* ===== cards ===== */
.card{
  position:relative;
  background:linear-gradient(160deg,rgba(36,26,84,.92),rgba(8,10,24,.92));
  border:1px solid rgba(110,140,255,.34);
  border-radius:var(--radius);
  box-shadow:var(--shadow-layer);
  padding:clamp(18px,2.2vw,28px);
  transition:transform .16s ease,box-shadow .16s ease,border-color .16s ease;
}
.card::after{
  content:"";position:absolute;left:0;bottom:0;height:2px;width:38%;
  background:linear-gradient(90deg,var(--electric),var(--lime));
  transform:scaleX(0);transform-origin:left;transition:transform .16s ease;
}
.card:hover,.card:focus-within{transform:translateY(-4px);border-color:var(--lime);box-shadow:0 4px 0 rgba(8,10,24,.4),0 20px 40px rgba(61,123,255,.28)}
.card:hover::after,.card:focus-within::after{transform:scaleX(1)}
.card__title{font-family:var(--font-sub);font-weight:700;font-size:clamp(18px,1.8vw,22px);line-height:1.3;color:var(--paper)}
.card__meta{font-family:var(--font-mono);font-size:12px;letter-spacing:.14em;color:var(--grey-violet);text-transform:uppercase;margin-top:6px}
.card__body{font-size:15px;line-height:1.7;color:#D5D5E4;margin-top:10px}

/* ===== stats ===== */
.stat{display:flex;flex-direction:column;gap:4px;padding:14px 0;border-top:1px solid rgba(245,243,236,.14)}
.stat__value{font-family:var(--font-mono);font-weight:600;font-size:clamp(20px,2.4vw,56px);letter-spacing:.02em;color:var(--lime);line-height:1.1}
.stat__label{font-family:var(--font-body);font-size:12px;letter-spacing:.16em;color:var(--grey-violet)}

/* ===== media ===== */
.media{position:relative;overflow:hidden;border-radius:var(--radius);border:var(--hair);background:linear-gradient(140deg,var(--plum),var(--ink-blue))}
.media__img{width:100%;height:100%;object-fit:cover;display:block;filter:saturate(1.05) contrast(1.05)}
.media--keyhole{aspect-ratio:3/4}
.media--wide{aspect-ratio:16/9}
.media--square{aspect-ratio:1/1}
.media__caption{font-family:var(--font-mono);font-size:12px;letter-spacing:.12em;color:var(--grey-violet);margin-top:8px}

/* ===== reveal ===== */
.reveal{opacity:0;transform:translateY(6px);transition:opacity .32s ease,transform .32s ease}
.reveal.is-visible{opacity:1;transform:none}

/* ===== toc dots ===== */
.toc-dots{
  position:fixed;right:14px;top:50%;transform:translateY(-50%);z-index:60;
  display:flex;flex-direction:column;gap:12px;
}
.toc-dots__dot{
  width:10px;height:10px;border-radius:50%;
  border:1px solid rgba(245,243,236,.4);background:transparent;
  transition:background-color .16s ease,border-color .16s ease,transform .16s ease;
}
.toc-dots__dot[aria-current="true"]{background:var(--lime);border-color:var(--lime);transform:scale(1.25)}
.toc-dots__dot:hover{border-color:var(--lime)}

/* ===== footer ===== */
.site-footer{
  background:linear-gradient(180deg,var(--ink-blue) 0%,#0A0D22 55%,#0D1030 100%);
  border-top:var(--hair);
  padding:clamp(48px,6vw,88px) 0 32px;
  color:#D5D5E4;
}
.footer-grid{
  display:grid;
  grid-template-columns:1.4fr 1fr 1fr 1.2fr;
  gap:clamp(24px,3vw,52px);
}
.footer-brand{font-family:var(--font-display);font-weight:900;font-size:clamp(22px,2.2vw,30px);letter-spacing:-.03em;color:var(--paper)}
.footer-line{font-size:14px;line-height:1.7;color:var(--grey-violet);margin-top:10px;max-width:34ch}
.footer-round{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin-top:16px}
.footer-round__note{font-family:var(--font-mono);font-size:12px;letter-spacing:.12em;color:var(--grey-violet)}
.footer-col__title{
  font-family:var(--font-mono);font-size:12px;font-weight:600;letter-spacing:.18em;text-transform:uppercase;
  color:var(--tag-gold);margin-bottom:16px;
}
.footer-list{display:flex;flex-direction:column;gap:10px;font-size:14px}
.footer-list a{color:#C3C3D6;border-bottom:1px solid transparent;transition:color .16s ease,border-color .16s ease}
.footer-list a:hover{color:var(--lime);border-bottom-color:var(--lime)}
.footer-list--plain li{color:var(--grey-violet);line-height:1.6;word-break:break-word}
.footer-rule{height:1px;background:linear-gradient(90deg,rgba(198,255,61,.6),rgba(61,123,255,.4) 40%,transparent);margin:clamp(32px,4vw,56px) 0 20px}
.footer-meta{
  display:flex;flex-wrap:wrap;gap:10px 28px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--grey-violet);
}

/* ===== responsive ===== */
@media (max-width:1024px){
  .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
  .nav-index__list{gap:10px}
  .nav-index__link{font-size:11px;letter-spacing:.12em}
}
@media (max-width:820px){
  :root{--header-h:72px;--header-h-condensed:60px}
  .site-header__inner{grid-template-columns:1fr auto;gap:12px}
  .header-pulse{display:none}
  .nav-toggle{display:inline-flex}
  .nav-index{justify-content:flex-end}
  .site-nav{
    position:absolute;left:0;right:0;top:100%;
    background:linear-gradient(180deg,rgba(13,16,48,.98),rgba(8,10,24,.98));
    border-bottom:var(--hair);
    max-height:0;overflow:hidden;
    transition:max-height .22s ease;
  }
  .site-nav[data-open]{
    max-height:70vh;overflow:auto;
  }
  .nav-index__list{flex-direction:column;align-items:stretch;gap:0;padding:8px var(--gutter) 18px}
  .nav-index__link{
    display:block;font-size:13px;letter-spacing:.14em;
    padding:14px 0;border-bottom:1px solid rgba(245,243,236,.12);
  }
  .nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1){transform:translateY(6px) rotate(45deg)}
  .nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2){opacity:0}
  .nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3){transform:translateY(-6px) rotate(-45deg)}
  .toc-dots{display:none}
}
@media (max-width:560px){
  body{font-size:16px}
  .footer-grid{grid-template-columns:1fr;gap:28px}
  .footer-meta{flex-direction:column;gap:8px}
  .paper{padding:20px}
}

/* ===== reduced motion ===== */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important;scroll-behavior:auto !important}
  .reveal{opacity:1;transform:none}
  .header-pulse{animation:none;background-position:0 0}
  .card:hover,.card:focus-within{transform:none}
  .btn--primary:hover{transform:none}
}