:root{
  --ink-900:#061A2B;
  --ink-700:#0C2C45;
  --teal-600:#0F3B44;
  --violet-700:#3B1E4E;
  --wine-700:#5C1F35;
  --accent-400:#3DE0C8;
  --accent-200:#9BF3E4;
  --coral-500:#FF6B4A;
  --paper-100:#F2F6F7;
  --mist-300:#C7D6DD;
  --line-500:#4A6572;
  --line-soft:rgba(74,101,114,.55);
  --font-sans:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;
  --shell:1320px;
  --gutter:clamp(18px,4vw,56px);
  --baseline:24px;
  --ease:cubic-bezier(.2,.7,.2,1);
  --t-fast:160ms;
  --t-mid:200ms;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  background-color:var(--ink-900);
  color:var(--paper-100);
  font-family:var(--font-sans);
  font-size:16px;
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:0;
  pointer-events:none;
  background-image:
    linear-gradient(to right,rgba(74,101,114,.16) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(74,101,114,.10) 1px,transparent 1px);
  background-size:96px 96px,96px 96px;
}
main{position:relative;z-index:1;display:block}
h1,h2,h3,h4,p,figure,blockquote,ul,ol{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%;height:auto}
button{font:inherit;color:inherit;background:none;border:0}
a{color:inherit}
:focus-visible{outline:2px solid var(--accent-400);outline-offset:3px}
p{max-width:none}

.skip-link{
  position:absolute;
  left:var(--gutter);
  top:-140px;
  z-index:200;
  display:inline-block;
  padding:12px 22px;
  background:var(--accent-400);
  color:var(--ink-900);
  font-weight:800;
  font-size:14px;
  letter-spacing:.04em;
  text-decoration:none;
  transition:top var(--t-fast) var(--ease);
}
.skip-link:focus{top:12px}

/* ---------------- Header ---------------- */
.site-header{
  position:sticky;
  top:0;
  z-index:60;
  background-color:var(--ink-900);
  border-bottom:1px solid var(--line-500);
  transition:border-color var(--t-mid) var(--ease);
}
.site-header[data-nav-open]{border-bottom-color:var(--accent-400)}
.header-ticks{
  position:absolute;
  top:0;
  left:0;
  right:0;
  height:6px;
  pointer-events:none;
  background-image:repeating-linear-gradient(to right,var(--line-500) 0 1px,transparent 1px 32px);
  opacity:.55;
}
.header-inner{
  position:relative;
  max-width:var(--shell);
  margin-inline:auto;
  padding:0 var(--gutter);
}
.header-top{
  position:relative;
  display:flex;
  flex-direction:column;
  align-items:center;
  padding:24px 0 16px;
}
.brand{
  display:inline-flex;
  flex-direction:column;
  align-items:center;
  text-decoration:none;
  color:var(--paper-100);
}
.brand-cn{
  font-size:clamp(30px,4.6vw,52px);
  font-weight:900;
  line-height:1.04;
  letter-spacing:-.01em;
}
.brand-sub{
  margin-top:9px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--mist-300);
}
.brand:hover .brand-cn{color:var(--accent-200)}
.masthead-version{
  position:absolute;
  right:0;
  top:26px;
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  color:var(--mist-300);
  text-transform:uppercase;
}
.masthead-dot{
  width:6px;
  height:6px;
  background:var(--accent-400);
  display:inline-block;
}
.nav-toggle{
  display:none;
  align-items:center;
  gap:10px;
  padding:9px 14px;
  border:1px solid var(--line-500);
  color:var(--paper-100);
  cursor:pointer;
  transition:border-color var(--t-fast) var(--ease),color var(--t-fast) var(--ease);
}
.nav-toggle:hover{border-color:var(--accent-400);color:var(--accent-400)}
.nav-toggle-label{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.18em;
}
.nav-toggle-box{
  display:inline-flex;
  flex-direction:column;
  justify-content:space-between;
  width:18px;
  height:12px;
}
.nav-toggle-bar{
  display:block;
  height:2px;
  width:100%;
  background:currentColor;
  transition:transform var(--t-fast) var(--ease),opacity var(--t-fast) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(5px) 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(-5px) rotate(-45deg)}

.primary-nav{
  border-top:1px solid var(--line-500);
  padding-top:0;
}
.nav-list{
  display:grid;
  grid-template-columns:repeat(6,minmax(0,1fr));
  gap:0;
}
.nav-item{
  border-right:1px solid var(--line-soft);
  border-bottom:1px solid var(--line-soft);
}
.nav-item:first-child{border-left:1px solid var(--line-soft)}
.nav-link{
  position:relative;
  display:block;
  padding:17px 8px 16px;
  text-align:center;
  text-decoration:none;
  color:var(--mist-300);
  font-size:clamp(16px,1.35vw,20px);
  font-weight:800;
  letter-spacing:.02em;
  transition:color var(--t-fast) var(--ease);
}
.nav-link::after{
  content:"";
  position:absolute;
  left:10px;
  right:10px;
  bottom:-1px;
  height:2px;
  background:var(--accent-400);
  transform:scaleX(0);
  transform-origin:0 50%;
  transition:transform var(--t-mid) var(--ease);
}
.nav-link:hover{color:var(--paper-100)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--accent-400)}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}

.scroll-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:-1px;
  height:2px;
  background:var(--accent-400);
  transform:scaleX(0);
  transform-origin:0 50%;
  pointer-events:none;
}

/* ---------------- Footer ---------------- */
.site-footer{
  position:relative;
  z-index:1;
  margin-top:clamp(64px,8vw,104px);
  background-color:var(--teal-600);
  border-top:1px solid var(--line-500);
  color:var(--paper-100);
}
.footer-inner{
  max-width:var(--shell);
  margin-inline:auto;
  padding:56px var(--gutter) 34px;
}
.footer-top{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:14px 32px;
  padding-bottom:26px;
  border-bottom:1px solid var(--line-soft);
}
.footer-brand{
  font-size:clamp(26px,3.4vw,40px);
  font-weight:900;
  line-height:1.1;
  letter-spacing:-.01em;
  text-decoration:none;
  color:var(--paper-100);
  transition:color var(--t-fast) var(--ease);
}
.footer-brand:hover{color:var(--accent-400)}
.footer-meta{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--mist-300);
}
.footer-nav{
  padding:26px 0;
  border-bottom:1px solid var(--line-soft);
}
.footer-nav-list{
  display:grid;
  grid-template-columns:repeat(6,minmax(0,1fr));
  gap:0;
}
.footer-nav-item{border-left:1px solid var(--line-soft)}
.footer-nav-item:first-child{border-left:0}
.footer-nav-link{
  display:block;
  padding:12px 14px;
  text-decoration:none;
  color:var(--mist-300);
  font-size:15px;
  font-weight:800;
  transition:color var(--t-fast) var(--ease),background-color var(--t-fast) var(--ease);
}
.footer-nav-link:hover{color:var(--accent-400);background-color:rgba(61,224,200,.07)}
.footer-index{
  display:block;
  margin-bottom:5px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  color:var(--mist-300);
  opacity:.72;
  transition:color var(--t-fast) var(--ease),opacity var(--t-fast) var(--ease);
}
.footer-nav-link:hover .footer-index{color:var(--coral-500);opacity:1}
.footer-mid{
  display:grid;
  grid-template-columns:1.25fr 1fr;
  gap:32px 56px;
  padding:32px 0;
  border-bottom:1px solid var(--line-soft);
}
.footer-heading{
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:700;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--accent-200);
}
.contact-list{display:grid;gap:10px}
.contact-row{
  display:grid;
  grid-template-columns:56px minmax(0,1fr);
  gap:14px;
  align-items:baseline;
}
.contact-key{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--mist-300);
}
.contact-val{
  font-size:15px;
  line-height:1.6;
  color:var(--paper-100);
  word-break:break-word;
}
.footer-note{
  margin-bottom:8px;
  max-width:36ch;
  font-size:14px;
  line-height:1.7;
  color:var(--mist-300);
}
.footer-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  padding-top:24px;
}
.footer-legal{
  font-size:13px;
  color:var(--mist-300);
}
.legal-nav{
  display:flex;
  flex-wrap:wrap;
  gap:8px 22px;
}
.legal-nav a{
  font-size:13px;
  text-decoration:none;
  color:var(--mist-300);
  border-bottom:1px solid transparent;
  padding-bottom:2px;
  transition:color var(--t-fast) var(--ease),border-color var(--t-fast) var(--ease);
}
.legal-nav a:hover{color:var(--accent-400);border-bottom-color:var(--accent-400)}
.to-top{
  padding:8px 15px;
  border:1px solid var(--line-500);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  color:var(--mist-300);
  cursor:pointer;
  opacity:.6;
  transition:opacity var(--t-fast) var(--ease),color var(--t-fast) var(--ease),border-color var(--t-fast) var(--ease);
}
.to-top[data-visible]{opacity:1}
.to-top:hover,.to-top:focus-visible{opacity:1;color:var(--accent-400);border-color:var(--accent-400)}

/* ---------------- Shared primitives ---------------- */
.container{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--baseline);
}
.blueprint-meta{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:8px 24px;
  padding-bottom:10px;
  margin-bottom:32px;
  border-bottom:1px solid var(--line-500);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--mist-300);
}
.section-head{
  display:flex;
  align-items:baseline;
  gap:16px;
  margin-bottom:26px;
}
.section-num{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.18em;
  color:var(--coral-500);
}
.section-title{
  font-size:clamp(26px,3.2vw,40px);
  font-weight:900;
  line-height:1.15;
  letter-spacing:-.01em;
}
.hairline{
  height:0;
  border:0;
  border-top:1px solid var(--line-soft);
  margin:clamp(32px,5vw,56px) 0;
}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.annotation{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--mist-300);
  writing-mode:vertical-rl;
}
.lede{
  font-size:clamp(18px,1.9vw,21px);
  line-height:1.7;
  color:var(--paper-100);
  max-width:60ch;
}
.prose{
  max-width:68ch;
  font-size:16px;
  line-height:1.75;
  color:var(--paper-100);
}
.prose p{margin-bottom:18px}
.prose h2{
  margin:48px 0 16px;
  font-size:clamp(24px,2.8vw,32px);
  font-weight:900;
  line-height:1.25;
  letter-spacing:-.01em;
}
.prose h3{
  margin:32px 0 12px;
  font-size:20px;
  font-weight:800;
  line-height:1.35;
}
.prose ul,.prose ol{
  margin:0 0 18px;
  padding-left:1.3em;
}
.prose ul{list-style:disc}
.prose ol{list-style:decimal}
.prose li{margin-bottom:8px}
.prose a{
  color:var(--accent-200);
  text-decoration:underline;
  text-underline-offset:4px;
  text-decoration-thickness:1px;
  transition:color var(--t-fast) var(--ease);
}
.prose a:hover{color:var(--accent-400)}
.prose strong{font-weight:800;color:var(--paper-100)}

.btn{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:13px 24px;
  border:1px solid var(--accent-400);
  color:var(--accent-400);
  background-color:transparent;
  font-size:15px;
  font-weight:800;
  letter-spacing:.02em;
  text-decoration:none;
  cursor:pointer;
  transition:background-color var(--t-mid) var(--ease),color var(--t-mid) var(--ease),border-color var(--t-mid) var(--ease);
}
.btn:hover{background-color:var(--accent-400);color:var(--ink-900)}
.btn--solid{background-color:var(--accent-400);color:var(--ink-900)}
.btn--solid:hover{background-color:var(--accent-200);border-color:var(--accent-200)}
.btn--quiet{border-color:var(--line-500);color:var(--paper-100)}
.btn--quiet:hover{background-color:transparent;border-color:var(--accent-400);color:var(--accent-400)}

.breadcrumb{
  margin-bottom:28px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--mist-300);
}
.breadcrumb-list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
}
.breadcrumb-list li{display:inline-flex;align-items:center;gap:8px}
.breadcrumb-list li + li::before{
  content:"/";
  color:var(--line-500);
}
.breadcrumb-list a{
  text-decoration:none;
  color:var(--mist-300);
  transition:color var(--t-fast) var(--ease);
}
.breadcrumb-list a:hover{color:var(--accent-400)}
.breadcrumb-list [aria-current="page"]{color:var(--paper-100)}

.card{
  position:relative;
  display:block;
  padding:22px 24px 24px;
  background-color:var(--ink-700);
  border:1px solid var(--line-500);
  text-decoration:none;
  color:var(--paper-100);
  transition:transform var(--t-mid) var(--ease),border-color var(--t-mid) var(--ease),box-shadow var(--t-mid) var(--ease);
}
.card:hover,.card:focus-visible{
  transform:translateY(-2px);
  border-color:var(--accent-400);
  box-shadow:0 0 0 1px var(--accent-400),0 14px 30px -22px rgba(0,0,0,.95);
}
.card-index{
  display:block;
  margin-bottom:10px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  color:var(--mist-300);
  transition:color var(--t-fast) var(--ease);
}
.card:hover .card-index,.card:focus-visible .card-index{color:var(--coral-500)}
.card-title{
  margin-bottom:8px;
  font-size:20px;
  font-weight:800;
  line-height:1.35;
  letter-spacing:-.01em;
}
.card-body{
  font-size:15px;
  line-height:1.7;
  color:var(--mist-300);
}

.panel{
  padding:20px 24px;
  background-color:var(--ink-700);
  border:1px solid var(--line-500);
  border-left:3px solid var(--accent-400);
}
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 8px;
  border:1px solid var(--line-500);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--mist-300);
}
.tag--alert{border-color:var(--coral-500);color:var(--coral-500)}
.tag--live{border-color:var(--accent-400);color:var(--accent-400)}

.media-frame{
  position:relative;
  margin:0;
  overflow:hidden;
  aspect-ratio:16 / 9;
  border:1px solid var(--line-500);
  background-color:var(--ink-700);
  background-image:
    linear-gradient(to right,rgba(74,101,114,.35) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(74,101,114,.35) 1px,transparent 1px);
  background-size:32px 32px;
}
.media-frame > img{
  width:100%;
  height:100%;
  object-fit:cover;
}
.media-frame__caption{
  position:absolute;
  left:0;
  bottom:0;
  max-width:calc(100% - 48px);
  padding:8px 12px;
  background-color:rgba(6,26,43,.85);
  border-top:1px solid var(--line-500);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--mist-300);
}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--tall{aspect-ratio:4 / 5}
.media-frame--slice{
  clip-path:polygon(0 0,100% 0,100% 100%,0 calc(100% - 6%));
  border:0;
}

/* ---------------- Responsive ---------------- */
@media (max-width:1100px){
  .footer-mid{gap:28px 40px}
  .nav-link{font-size:16px;padding:15px 6px 14px}
}

@media (max-width:899px){
  .header-top{
    flex-direction:row;
    align-items:center;
    justify-content:space-between;
    padding:12px 0;
  }
  .brand{align-items:flex-start}
  .brand-cn{font-size:26px}
  .brand-sub{display:none}
  .masthead-version{display:none}
  .nav-toggle{display:inline-flex}
  .primary-nav{display:none;border-top:0}
  .primary-nav[data-open]{
    display:block;
    margin-top:6px;
    padding-bottom:12px;
    border-top:1px solid var(--line-500);
    max-height:calc(100dvh - 96px);
    overflow-y:auto;
  }
  .nav-list{grid-template-columns:1fr}
  .nav-item,
  .nav-item:first-child{
    border-left:0;
    border-right:0;
    border-bottom:1px solid var(--line-soft);
  }
  .nav-item:first-child{border-top:1px solid var(--line-soft)}
  .nav-link{
    padding:16px 4px;
    text-align:left;
    font-size:22px;
    font-weight:900;
  }
  .nav-link::after{left:4px;right:auto;width:56px}
  .nav-link:hover::after,
  .nav-link[aria-current="page"]::after{transform:scaleX(1)}

  .footer-nav-list{grid-template-columns:repeat(3,minmax(0,1fr))}
  .footer-nav-item:nth-child(4){border-left:0}
  .footer-nav-item:nth-child(n+4){border-top:1px solid var(--line-soft)}
  .footer-mid{grid-template-columns:1fr}
  .footer-bottom{justify-content:flex-start}
}

@media (max-width:640px){
  .grid-12{grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}
  .header-ticks{height:4px;background-image:repeating-linear-gradient(to right,var(--line-500) 0 1px,transparent 1px 24px)}
  .blueprint-meta{font-size:10px;letter-spacing:.14em}
  .footer-inner{padding:40px var(--gutter) 28px}
  .footer-nav-list{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-nav-item:nth-child(4){border-left:1px solid var(--line-soft)}
  .footer-nav-item:nth-child(odd){border-left:0}
  .footer-nav-item:nth-child(n+3){border-top:1px solid var(--line-soft)}
  .contact-row{grid-template-columns:1fr;gap:2px}
  .footer-note{max-width:none}
  .legal-nav{gap:8px 18px}
  .btn{width:100%;justify-content:center}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.01ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.01ms !important;
    scroll-behavior:auto !important;
  }
  .card:hover,.card:focus-visible{transform:none}
}