:root{
  --ink:#07182E;
  --ink-2:#0E2A47;
  --steel:#173F5F;
  --ice:#56C7F2;
  --cyan:#6EF7DE;
  --orange:#FF6B1A;
  --amber:#FFB65C;
  --paper:#F6F9FC;
  --mist:#B9CBD9;
  --indigo:#3D2C6B;
  --wine:#6B1E35;
  --line:rgba(185,203,217,.20);
  --line-strong:rgba(185,203,217,.38);
  --body-font:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --mono-font:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --max:1440px;
  --gutter:clamp(20px,4vw,56px);
  --header-h:84px;
  --ease:cubic-bezier(.2,.7,.2,1);
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,p,ul,ol,li,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
img,svg{display:block;max-width:100%}
button{font:inherit;color:inherit;background:none;border:0}
a{color:inherit}
[hidden]{display:none!important}
body{
  min-height:100vh;
  background-color:var(--ink);
  background-image:
    radial-gradient(1100px 620px at 92% -12%, rgba(86,199,242,.16), rgba(86,199,242,0) 68%),
    radial-gradient(760px 520px at 2% 4%, rgba(61,44,107,.40), rgba(61,44,107,0) 70%),
    linear-gradient(rgba(86,199,242,.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(86,199,242,.06) 1px, transparent 1px);
  background-size:auto,auto,48px 48px,48px 48px;
  color:var(--paper);
  font-family:var(--body-font);
  font-size:16px;
  line-height:1.75;
  letter-spacing:.005em;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
h1,h2,h3,h4{font-weight:900;line-height:1.15;letter-spacing:-.02em;color:var(--paper)}
h1{font-size:clamp(34px,5vw,64px)}
h2{font-size:clamp(24px,3vw,36px)}
h3{font-size:clamp(19px,2vw,24px)}
p{max-width:72ch}
strong,b{font-weight:700;color:var(--paper)}
::selection{background:var(--cyan);color:#04202A}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:2px}
#main-content{scroll-margin-top:calc(var(--header-h) + 16px)}
.bb-skip{
  position:fixed;left:16px;top:-80px;z-index:300;
  display:inline-block;padding:10px 16px;
  background:var(--cyan);color:#04202A;
  font:700 14px/1.2 var(--body-font);letter-spacing:.02em;
  border-radius:2px;text-decoration:none;
  transition:top .16s var(--ease);
}
.bb-skip:focus{top:16px}

/* ---------- 布局工具 ---------- */
.bb-container{width:100%;max-width:var(--max);margin-inline:auto;padding-inline:var(--gutter)}
.bb-section{padding-block:clamp(44px,6vw,88px)}
.bb-section__head{display:grid;gap:10px;margin-bottom:clamp(22px,3vw,40px);max-width:52ch}
.bb-grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(16px,2vw,28px)}
.bb-rule{height:1px;border:0;margin:0;background:var(--line)}

/* ---------- 文字与数据 ---------- */
.bb-kicker{
  display:inline-flex;align-items:center;gap:8px;
  font:700 12px/1 var(--mono-font);letter-spacing:.18em;text-transform:uppercase;color:var(--ice);
}
.bb-kicker::before{content:"";width:18px;height:1px;background:var(--orange)}
.bb-data{font:700 1em/1 var(--mono-font);letter-spacing:.02em;color:var(--amber)}
.bb-prose{max-width:70ch;color:#D9E5F0;font-size:clamp(15px,1.05vw,17px);line-height:1.9}
.bb-prose h2{margin:1.6em 0 .5em;font-size:clamp(22px,2.4vw,30px)}
.bb-prose h3{margin:1.4em 0 .4em;font-size:clamp(18px,1.8vw,22px);color:var(--paper)}
.bb-prose p{margin:0 0 1.1em}
.bb-prose ul,.bb-prose ol{margin:0 0 1.2em;padding-left:1.25em;list-style:disc}
.bb-prose ol{list-style:decimal}
.bb-prose li{margin-bottom:.5em}
.bb-prose a{color:var(--ice);text-decoration:underline;text-underline-offset:3px;text-decoration-thickness:1px}
.bb-prose a:hover{color:var(--cyan)}
.bb-prose blockquote{
  margin:1.4em 0;padding:14px 18px;
  border-left:2px solid var(--orange);
  background:rgba(14,42,71,.55);color:var(--mist);
}
.bb-prose code{font:600 .9em/1.4 var(--mono-font);color:var(--amber)}

/* ---------- 面包屑与索引 ---------- */
.bb-breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  margin:0 0 clamp(18px,2.4vw,28px);
  font:500 12px/1.6 var(--mono-font);letter-spacing:.06em;color:var(--mist);
}
.bb-breadcrumb li+li::before{content:"/";margin-right:8px;color:var(--steel)}
.bb-breadcrumb a{color:var(--mist);text-decoration:none;transition:color .16s var(--ease)}
.bb-breadcrumb a:hover{color:var(--cyan)}
.bb-breadcrumb [aria-current="page"]{color:var(--paper);font-weight:700}
.bb-index{
  position:sticky;top:calc(var(--header-h) + 20px);
  border-left:1px solid var(--line-strong);
  padding-left:16px;
  font:500 13px/1.6 var(--mono-font);color:var(--mist);
}
.bb-index a{display:block;padding:5px 0;color:var(--mist);text-decoration:none;transition:color .16s var(--ease)}
.bb-index a:hover,.bb-index a[aria-current="true"]{color:var(--cyan)}
.bb-aside{border-top:1px solid var(--line);padding-top:16px;font-size:14px;line-height:1.7;color:var(--mist);max-width:38ch}

/* ---------- 卡片与标签 ---------- */
.bb-card{
  position:relative;
  background:rgba(14,42,71,.62);
  border:1px solid var(--line);
  padding:clamp(18px,2.2vw,28px);
  transition:border-color .18s var(--ease),transform .18s var(--ease);
}
.bb-card::before{
  content:"";position:absolute;inset:0 0 auto 0;height:2px;
  background:linear-gradient(90deg,var(--ice),rgba(86,199,242,0));
  opacity:.75;
}
.bb-card:hover{border-color:var(--line-strong);transform:translateY(-2px)}
.bb-card__title{font-size:clamp(18px,1.9vw,22px);font-weight:800;letter-spacing:-.01em;line-height:1.3;margin:0 0 8px}
.bb-card__meta{font:500 12px/1.6 var(--mono-font);letter-spacing:.05em;color:var(--mist)}
.bb-pill{
  display:inline-flex;align-items:center;gap:6px;
  padding:6px 10px;border-radius:999px;
  font:600 12px/1 var(--mono-font);letter-spacing:.08em;
  color:var(--mist);background:rgba(23,63,95,.55);border:1px solid var(--line-strong);
}
.bb-pill--live{color:var(--cyan);border-color:rgba(110,247,222,.48);background:rgba(110,247,222,.10)}
.bb-pill--warm{color:var(--amber);border-color:rgba(255,182,92,.48);background:rgba(255,182,92,.10)}
.bb-pill--risk{color:#FFD6E0;border-color:rgba(107,30,53,.9);background:rgba(107,30,53,.55)}
.bb-step{
  position:relative;
  border:1px solid var(--line);
  background:rgba(14,42,71,.55);
  padding:18px 20px;
}
.bb-step__num{display:block;margin-bottom:8px;font:800 12px/1 var(--mono-font);letter-spacing:.18em;color:var(--orange)}

/* ---------- 图片容器 ---------- */
.bb-media{
  position:relative;display:block;overflow:hidden;
  aspect-ratio:16/10;
  border:1px solid var(--line);
  background:
    linear-gradient(140deg,var(--ink-2),var(--steel) 70%,rgba(61,44,107,.6));
}
.bb-media img{width:100%;height:100%;object-fit:cover;display:block}
.bb-media::after{
  content:"";position:absolute;right:12px;bottom:12px;width:28px;height:28px;
  border-right:1px solid rgba(110,247,222,.7);
  border-bottom:1px solid rgba(110,247,222,.7);
  pointer-events:none;
}
.bb-media--wide{aspect-ratio:21/9}
.bb-media--tall{aspect-ratio:3/4}

/* ---------- 按钮 ---------- */
.bb-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:12px 20px;border-radius:2px;
  border:1px solid transparent;
  font:600 14px/1.2 var(--body-font);letter-spacing:.02em;
  text-decoration:none;cursor:pointer;
  transition:background-color .16s var(--ease),border-color .16s var(--ease),color .16s var(--ease),transform .16s var(--ease);
}
.bb-btn--primary{background:var(--orange);border-color:var(--orange);color:#0A1420}
.bb-btn--primary:hover{background:var(--amber);border-color:var(--amber);transform:translateY(-1px)}
.bb-btn--ghost{background:transparent;border-color:var(--steel);color:var(--paper)}
.bb-btn--ghost:hover{border-color:var(--ice);color:var(--ice)}
.bb-btn--sm{padding:9px 14px;font-size:13px}

/* ---------- 筛选 ---------- */
.bb-filter{display:flex;flex-wrap:wrap;gap:8px}
.bb-filter__btn{
  padding:9px 14px;border-radius:999px;
  border:1px solid var(--line-strong);
  background:rgba(14,42,71,.7);color:var(--mist);
  font:600 13px/1 var(--body-font);letter-spacing:.02em;cursor:pointer;
  transition:background-color .16s var(--ease),border-color .16s var(--ease),color .16s var(--ease);
}
.bb-filter__btn:hover{color:var(--paper);border-color:var(--ice)}
.bb-filter__btn[aria-pressed="true"]{background:var(--cyan);border-color:var(--cyan);color:#04202A}

/* ---------- 显现 ---------- */
.bb-reveal{opacity:0;transform:translateY(14px);transition:opacity .24s var(--ease),transform .24s var(--ease)}
.bb-reveal.is-visible{opacity:1;transform:none}

/* ---------- 头部 ---------- */
.bb-header{position:sticky;top:0;z-index:90;padding:14px var(--gutter) 0}
.bb-progress{
  position:absolute;left:0;right:0;top:0;height:2px;
  background:linear-gradient(90deg,var(--ice),var(--cyan));
  transform:scaleX(0);transform-origin:0 50%;
  transition:transform .12s linear;
}
.bb-header__rail{
  position:relative;max-width:var(--max);margin-inline:auto;
  background:rgba(7,24,46,.88);
  border:1px solid var(--line-strong);
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
  transition:box-shadow .18s var(--ease);
}
.bb-header__rail::after{
  content:"";position:absolute;right:0;top:0;width:11px;height:11px;
  border-top:1px solid var(--cyan);border-right:1px solid var(--cyan);
  opacity:.75;pointer-events:none;
}
.bb-header[data-scrolled] .bb-header__rail{box-shadow:0 16px 40px rgba(3,10,20,.6);border-color:var(--line-strong)}
.bb-header__grid{
  display:grid;grid-template-columns:auto minmax(0,1fr) auto;
  align-items:center;gap:clamp(12px,2vw,28px);
  padding:12px clamp(14px,2vw,22px);
  transition:padding .18s var(--ease);
}
.bb-header[data-scrolled] .bb-header__grid{padding-block:8px}
.bb-brand{
  display:inline-flex;align-items:center;gap:10px;
  text-decoration:none;color:var(--paper);min-width:0;
}
.bb-brand__glyph{
  display:grid;place-items:center;flex:none;
  width:34px;height:34px;border:1px solid var(--ice);border-radius:2px;
  color:var(--ice);font:800 16px/1 var(--mono-font);
  background:linear-gradient(160deg,rgba(86,199,242,.20),rgba(86,199,242,0));
}
.bb-brand__stack{display:flex;flex-direction:column;gap:2px;min-width:0}
.bb-brand__name{font:900 17px/1.1 var(--body-font);letter-spacing:-.01em;white-space:nowrap}
.bb-brand__meta{font:500 10px/1.2 var(--mono-font);letter-spacing:.16em;color:var(--mist);text-transform:uppercase;white-space:nowrap}
.bb-version-chip{
  flex:none;padding:4px 6px;border:1px solid rgba(255,182,92,.5);border-radius:2px;
  font:700 10px/1 var(--mono-font);letter-spacing:.1em;color:var(--amber);
}
.bb-version-chip--ghost{border-color:var(--line-strong);color:var(--mist)}
.bb-nav-toggle{
  display:none;align-items:center;gap:10px;
  padding:10px 14px;border:1px solid var(--line-strong);border-radius:2px;
  background:rgba(23,63,95,.55);color:var(--paper);
  font:700 13px/1 var(--body-font);letter-spacing:.06em;cursor:pointer;
  justify-self:end;
  transition:border-color .16s var(--ease),color .16s var(--ease);
}
.bb-nav-toggle:hover{border-color:var(--ice);color:var(--ice)}
.bb-nav-toggle__dots{display:grid;gap:3px;width:15px}
.bb-nav-toggle__dots span{display:block;height:2px;background:currentColor;transform-origin:50% 50%;transition:transform .16s var(--ease)}
.bb-nav-toggle__dots span:nth-child(2){width:72%}
.bb-nav-toggle__text{font-size:12px;letter-spacing:.14em}
.bb-header[data-open] .bb-nav-toggle__dots span:nth-child(1){transform:translateY(5px) rotate(45deg)}
.bb-header[data-open] .bb-nav-toggle__dots span:nth-child(2){opacity:0}
.bb-header[data-open] .bb-nav-toggle__dots span:nth-child(3){transform:translateY(-5px) rotate(-45deg)}
.bb-nav{justify-self:center;min-width:0}
.bb-nav__list{display:flex;align-items:center;gap:2px;flex-wrap:wrap;justify-content:center}
.bb-nav__link{
  display:inline-flex;align-items:center;
  padding:9px 13px;border-radius:999px;
  font:600 14px/1.2 var(--body-font);color:var(--mist);text-decoration:none;
  white-space:nowrap;
  transition:background-color .16s var(--ease),color .16s var(--ease);
}
.bb-nav__link:hover{color:var(--paper);background:rgba(86,199,242,.14)}
.bb-nav__link[aria-current="page"]{background:var(--cyan);color:#04202A;font-weight:800}
.bb-header__utility{display:flex;align-items:center;gap:14px;justify-self:end}
.bb-utility{display:flex;flex-direction:column;gap:3px;text-align:right;max-width:none}
.bb-utility__key{font:600 10px/1 var(--mono-font);letter-spacing:.16em;text-transform:uppercase;color:var(--mist)}
.bb-utility__val{font:600 12px/1.3 var(--mono-font);letter-spacing:.02em;color:var(--ice);white-space:nowrap}

/* ---------- 页脚 ---------- */
.bb-footer{
  position:relative;
  margin-top:clamp(56px,8vw,120px);
  border-top:1px solid var(--line-strong);
  background:linear-gradient(180deg,#061426 0%,#040C18 100%);
  padding-top:clamp(36px,5vw,68px);
}
.bb-footer::before{
  content:"";position:absolute;left:0;right:0;top:0;height:1px;
  background:linear-gradient(90deg,var(--ice),rgba(86,199,242,0) 55%,var(--orange));
  opacity:.6;
}
.bb-footer__grid{
  max-width:var(--max);margin-inline:auto;padding-inline:var(--gutter);
  display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;
  gap:clamp(22px,3.5vw,52px);
}
.bb-footer__col{min-width:0}
.bb-footer__col--brand{max-width:38ch}
.bb-footer__brand{
  display:flex;align-items:center;gap:10px;
  font:900 20px/1.2 var(--body-font);letter-spacing:-.01em;margin:0 0 12px;
}
.bb-footer__note{margin:0 0 16px;font-size:14px;line-height:1.7;color:var(--mist)}
.bb-footer__mono{font:600 11px/1.4 var(--mono-font);letter-spacing:.1em;color:rgba(185,203,217,.62);margin:0}
.bb-footer__title{
  font:700 12px/1 var(--mono-font);letter-spacing:.18em;text-transform:uppercase;
  color:var(--ice);margin:0 0 16px;
}
.bb-footer__list{display:grid;gap:10px}
.bb-footer__list a{
  font-size:14px;color:var(--mist);text-decoration:none;
  transition:color .16s var(--ease);
}
.bb-footer__list a:hover{color:var(--paper)}
.bb-footer__list a:focus-visible{color:var(--cyan)}
.bb-footer__contact{
  max-width:var(--max);margin:clamp(28px,4vw,48px) auto 0;
  padding:20px var(--gutter);
  border-top:1px solid var(--line);
  display:flex;flex-wrap:wrap;gap:12px 36px;
}
.bb-footer__contact-item{
  display:flex;align-items:baseline;gap:10px;
  font-size:13px;line-height:1.6;color:var(--mist);max-width:none;
}
.bb-footer__contact-item b{font:700 11px/1 var(--mono-font);letter-spacing:.16em;text-transform:uppercase;color:var(--ice)}
.bb-footer__base{
  max-width:var(--max);margin:0 auto;
  padding:18px var(--gutter) 30px;
  border-top:1px solid var(--line);
  display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px 24px;
  font:500 12px/1.6 var(--mono-font);letter-spacing:.04em;color:rgba(185,203,217,.68);
}
.bb-footer__legal{color:var(--amber)}

/* ---------- 响应式 ---------- */
@media (max-width:1079px){
  .bb-header__grid{grid-template-columns:minmax(0,1fr) auto;gap:12px}
  .bb-header__utility{display:none}
  .bb-nav-toggle{display:inline-flex}
  .bb-nav{
    position:absolute;top:calc(100% + 8px);left:0;right:0;
    justify-self:stretch;min-width:0;
    padding:12px;
    border:1px solid var(--line-strong);
    background:rgba(7,24,46,.98);
    backdrop-filter:blur(14px);
    -webkit-backdrop-filter:blur(14px);
    visibility:hidden;opacity:0;transform:translateY(-6px);
    transition:opacity .18s var(--ease),transform .18s var(--ease),visibility .18s linear;
    max-height:calc(100vh - 160px);overflow-y:auto;
  }
  .bb-header[data-open] .bb-nav{visibility:visible;opacity:1;transform:none}
  .bb-nav__list{flex-direction:column;align-items:stretch;gap:4px}
  .bb-nav__link{display:block;padding:12px 14px;border-radius:2px;font-size:15px}
  .bb-footer__grid{grid-template-columns:1fr 1fr}
  .bb-footer__col--brand{grid-column:1 / -1;max-width:52ch}
}
@media (max-width:900px){
  :root{--header-h:76px}
  .bb-grid{grid-template-columns:repeat(6,minmax(0,1fr))}
  .bb-section{padding-block:clamp(36px,6vw,60px)}
}
@media (max-width:640px){
  .bb-header{padding-top:10px}
  .bb-brand__meta{display:none}
  .bb-brand__name{font-size:16px}
  .bb-brand__glyph{width:30px;height:30px;font-size:15px}
  .bb-nav-toggle{padding:9px 11px}
  .bb-grid{grid-template-columns:minmax(0,1fr)}
  .bb-footer__grid{grid-template-columns:minmax(0,1fr);gap:28px}
  .bb-footer__contact{flex-direction:column;gap:10px}
  .bb-footer__base{flex-direction:column;align-items:flex-start}
}
@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;
  }
  .bb-reveal{opacity:1;transform:none}
  .bb-progress{transition:none}
  .bb-card:hover{transform:none}
  .bb-btn--primary:hover{transform:none}
}