*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body,h1,h2,h3,h4,h5,p,ul,ol,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
button{font:inherit;color:inherit}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:3px}

:root{
  --ink:#061A16;
  --ink-2:#0C2A24;
  --ink-3:#020B09;
  --line:#24443B;
  --text:#EAF7F1;
  --muted:#A8C3B8;
  --cyan:#3BF2D0;
  --orange:#FF8A3D;
  --paper:#E7E2D2;
  --blue:#7FD4FF;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-display:"Barlow Condensed","Oswald","Noto Sans SC","PingFang SC",system-ui,sans-serif;
  --font-mono:"IBM Plex Mono","Roboto Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --edge:clamp(16px,4vw,40px);
  --radius:2px;
  --anchor-offset:128px;
}

html{scroll-behavior:smooth}
body{
  min-height:100vh;
  background-color:var(--ink);
  background-image:
    radial-gradient(120% 58% at 50% -8%,rgba(59,242,208,.10),transparent 62%),
    radial-gradient(70% 40% at 100% 0%,rgba(255,138,61,.07),transparent 66%);
  background-repeat:no-repeat;
  color:var(--text);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  font-weight:400;
  overflow-x:hidden;
}
[id]{scroll-margin-top:var(--anchor-offset)}
main:focus,main:focus-visible{outline:none}

:where(a,button,[tabindex]):focus-visible{
  outline:2px solid var(--orange);
  outline-offset:3px;
  border-radius:var(--radius);
}
::selection{background:rgba(255,138,61,.85);color:var(--ink-3)}

/* ---------- 容器与章节 ---------- */
.fb-container{width:100%;max-width:1240px;margin-inline:auto;padding-inline:var(--edge)}
.fb-section{padding-block:clamp(40px,7vw,88px);border-top:1px solid rgba(36,68,59,.7)}
.fb-section:first-of-type{border-top:0}
.fb-divider{display:block;height:1px;border:0;background:var(--line);margin-block:clamp(24px,4vw,48px)}

/* ---------- 排版 ---------- */
.fb-kicker{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;
  text-transform:uppercase;color:var(--cyan);
}
.fb-kicker::before{content:"";width:20px;height:1px;background:currentColor;flex:0 0 auto}
.fb-display{
  font-family:var(--font-display);font-weight:400;
  font-size:clamp(48px,9vw,140px);line-height:.9;letter-spacing:-.02em;
  color:var(--text);
}
.fb-title{
  font-family:var(--font-display);font-weight:500;
  font-size:clamp(24px,3.4vw,40px);line-height:1.14;letter-spacing:-.01em;
  color:var(--text);
}
.fb-lead{font-size:clamp(17px,1.5vw,20px);line-height:1.7;color:var(--text);max-width:60ch}
.fb-text{font-size:17px;line-height:1.75;color:var(--muted);max-width:66ch}
.fb-mono{font-family:var(--font-mono);font-weight:600;letter-spacing:.03em;font-variant-numeric:tabular-nums}
.fb-link{color:var(--blue);text-decoration:underline;text-underline-offset:3px;text-decoration-thickness:1px}
.fb-link:hover{color:var(--cyan);text-decoration:underline}

.fb-list{display:grid;gap:10px;font-size:16px;line-height:1.7;color:var(--muted)}
.fb-list>li{position:relative;padding-left:18px}
.fb-list>li::before{content:"";position:absolute;left:0;top:.74em;width:8px;height:1px;background:var(--cyan)}

/* ---------- 画板 ---------- */
.fb-panel{
  position:relative;
  background:var(--ink-2);
  border:1px solid var(--line);
  border-radius:var(--radius);
  padding:clamp(18px,3vw,32px);
}
.fb-panel--paper{background:var(--paper);border-color:rgba(6,26,22,.25);color:#122620}
.fb-panel--paper .fb-text,.fb-panel--paper .fb-lead,.fb-panel--paper .fb-list{color:#2b443d}
.fb-panel--paper .fb-title,.fb-panel--paper .fb-display{color:#0d1f1a}
.fb-panel--paper .fb-kicker{color:#1c5c4b}
.fb-panel--stack{box-shadow:7px 7px 0 -1px var(--ink),7px 7px 0 0 var(--line)}

/* ---------- 标签 ---------- */
.fb-tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 9px;border:1px solid var(--line);
  background:rgba(36,68,59,.25);color:var(--muted);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  border-radius:var(--radius);white-space:nowrap;
}
.fb-tag--cyan{color:var(--cyan);border-color:rgba(59,242,208,.42);background:rgba(59,242,208,.08)}
.fb-tag--orange{color:var(--orange);border-color:rgba(255,138,61,.45);background:rgba(255,138,61,.1)}
.fb-tag--paper{color:#122620;background:var(--paper);border-color:rgba(6,26,22,.3)}

/* ---------- 按钮 ---------- */
.fb-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:12px 20px;border:1px solid var(--line);border-radius:var(--radius);
  background:transparent;color:var(--text);
  font-size:14px;font-weight:600;letter-spacing:.04em;line-height:1.2;
  cursor:pointer;transition:background .2s ease,color .2s ease,border-color .2s ease,box-shadow .2s ease;
}
.fb-btn:hover{text-decoration:none}
.fb-btn--primary{background:var(--orange);border-color:var(--orange);color:var(--ink)}
.fb-btn--primary:hover{background:#ffa063;border-color:#ffa063;color:var(--ink)}
.fb-btn--line{border-color:rgba(59,242,208,.45);color:var(--cyan)}
.fb-btn--line:hover{background:rgba(59,242,208,.1);border-color:var(--cyan);text-decoration:none}

/* ---------- 面包屑 ---------- */
.fb-breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  padding-block:16px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;color:var(--muted);
}
.fb-breadcrumb__link{color:var(--muted)}
.fb-breadcrumb__link:hover{color:var(--cyan);text-decoration:none}
.fb-breadcrumb__sep{color:var(--line)}
.fb-breadcrumb [aria-current="page"]{color:var(--text)}

/* ---------- 网格 ---------- */
.fb-grid{display:grid;gap:clamp(16px,2.4vw,28px)}
.fb-grid--split{grid-template-columns:minmax(230px,300px) minmax(0,1fr);align-items:start}
.fb-grid--cards{grid-template-columns:repeat(auto-fit,minmax(236px,1fr))}

/* ---------- 图片容器基础 ---------- */
.fb-media{
  position:relative;overflow:hidden;border:1px solid var(--line);border-radius:var(--radius);
  background:linear-gradient(160deg,#0D2E27,#020B09 70%);
  aspect-ratio:16/9;isolation:isolate;
}
.fb-media__img{width:100%;height:100%;object-fit:cover;display:block}
.fb-media__caption{
  position:absolute;left:0;right:0;bottom:0;z-index:1;
  padding:12px 14px;font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;
  color:var(--cyan);
  background:linear-gradient(180deg,rgba(6,26,22,0),rgba(2,11,9,.85));
}
.fb-media--wide{aspect-ratio:21/9}
.fb-media--tall{aspect-ratio:3/4}

/* ---------- 标签页组件 ---------- */
.fb-tabs{display:block}
.fb-tabs__list{display:flex;flex-wrap:wrap;gap:4px;border-bottom:1px solid var(--line);margin-bottom:22px}
.fb-tabs__tab{
  appearance:none;background:transparent;border:1px solid transparent;border-bottom:2px solid transparent;
  padding:10px 16px;margin-bottom:-1px;border-radius:var(--radius) var(--radius) 0 0;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--muted);cursor:pointer;
  transition:color .2s ease,background .2s ease,border-color .2s ease;
}
.fb-tabs__tab:hover{color:var(--text);background:rgba(59,242,208,.05)}
.fb-tabs__tab[aria-selected="true"]{color:var(--text);border-bottom-color:var(--orange);background:rgba(59,242,208,.06)}
.fb-tabs__panel{padding-block:4px}
.fb-tabs__panel[hidden]{display:none}

/* ---------- 入场渐显 ---------- */
.js-reveal [data-reveal]{opacity:0;transform:translateY(16px);transition:opacity .4s ease,transform .4s ease}
.js-reveal [data-reveal].is-in{opacity:1;transform:none}

/* ---------- 跳转链接 ---------- */
.fb-skip{
  position:fixed;top:10px;left:10px;z-index:300;
  padding:11px 18px;border-radius:var(--radius);
  background:var(--orange);color:var(--ink);
  font-size:13px;font-weight:700;letter-spacing:.04em;
  transform:translateY(-200%);transition:transform .2s ease;
}
.fb-skip:focus{transform:translateY(0);text-decoration:none}

/* ---------- 头部 ---------- */
.fb-header{
  position:sticky;top:0;z-index:80;
  background:rgba(6,26,22,.94);
  background-image:linear-gradient(180deg,rgba(59,242,208,.045),transparent 70%);
  border-bottom:1px solid var(--line);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  transition:box-shadow .25s ease,background-color .25s ease;
}
.fb-header.is-scrolled{background-color:rgba(6,26,22,.99);box-shadow:0 20px 44px -34px #000}
.fb-header a{color:inherit;text-decoration:none}

.fb-header__strip{
  border-bottom:1px solid rgba(36,68,59,.85);
  background-image:linear-gradient(90deg,rgba(59,242,208,.07),transparent 45%,rgba(255,138,61,.07));
}
.fb-strip{
  display:flex;align-items:center;gap:10px;
  min-height:32px;padding-block:6px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;color:var(--muted);
  overflow:hidden;
}
.fb-strip__text{flex:1 1 auto;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;line-height:1.4}
.fb-strip__dot{
  flex:0 0 auto;width:6px;height:6px;border-radius:50%;
  background:var(--cyan);box-shadow:0 0 0 3px rgba(59,242,208,.16);
  animation:fb-blink 2.6s ease-in-out 2;
}
.fb-strip__meta{flex:0 0 auto;color:var(--cyan);letter-spacing:.14em}
@keyframes fb-blink{
  0%,100%{opacity:1;box-shadow:0 0 0 3px rgba(59,242,208,.16)}
  50%{opacity:.4;box-shadow:0 0 0 6px rgba(59,242,208,.04)}
}

.fb-header__main{position:relative}
.fb-masthead{display:flex;align-items:center;gap:clamp(12px,2vw,28px);padding-block:11px;min-height:64px}

.fb-brand{display:flex;align-items:center;gap:11px;flex:0 0 auto;color:var(--text)}
.fb-brand__mark{
  display:grid;place-items:center;flex:0 0 auto;
  width:38px;height:38px;border:1px solid rgba(59,242,208,.55);border-radius:var(--radius);
  background:rgba(59,242,208,.07);color:var(--cyan);
  font-family:var(--font-mono);font-weight:700;font-size:13px;letter-spacing:.02em;
}
.fb-brand__text{display:block;min-width:0}
.fb-brand__name{
  display:block;font-family:var(--font-display);font-weight:600;
  font-size:20px;line-height:1.1;letter-spacing:.06em;color:var(--text);
}
.fb-brand__desc{
  display:block;margin-top:3px;
  font-family:var(--font-mono);font-size:10px;letter-spacing:.14em;line-height:1.4;color:var(--muted);
}

.fb-command{margin-left:auto}
.fb-command__list{display:flex;align-items:center;gap:2px}
.fb-command__link{
  position:relative;display:flex;align-items:baseline;gap:7px;
  padding:10px 12px;border-radius:var(--radius);
  font-size:14px;letter-spacing:.04em;color:var(--muted);
  transition:color .2s ease,background-color .2s ease;
}
.fb-command__link:hover{color:var(--text);background:rgba(59,242,208,.07);text-decoration:none}
.fb-command__index{
  font-family:var(--font-mono);font-size:10px;letter-spacing:.06em;
  color:rgba(168,195,184,.55);transition:color .2s ease;
}
.fb-command__link::after{
  content:"";position:absolute;left:12px;right:12px;bottom:3px;height:2px;
  background:var(--orange);transform:scaleX(0);transform-origin:left;
  transition:transform .24s ease;
}
.fb-command__link[aria-current="page"]{color:var(--text);background:rgba(255,138,61,.07)}
.fb-command__link[aria-current="page"]::after{transform:scaleX(1)}
.fb-command__link[aria-current="page"] .fb-command__index{color:var(--orange)}

.fb-header__actions{display:flex;align-items:center;gap:10px;flex:0 0 auto;margin-left:6px}
.fb-status{
  display:inline-flex;align-items:center;gap:7px;
  padding:6px 10px;border:1px solid rgba(59,242,208,.28);border-radius:var(--radius);
  background:rgba(59,242,208,.05);color:var(--cyan);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
}
.fb-status__dot{width:5px;height:5px;border-radius:50%;background:var(--cyan);box-shadow:0 0 6px rgba(59,242,208,.9)}
.fb-cta{
  display:inline-flex;align-items:center;gap:8px;
  padding:9px 16px;border:1px solid var(--orange);border-radius:var(--radius);
  background:var(--orange);color:var(--ink);
  font-size:13px;font-weight:700;letter-spacing:.04em;line-height:1.2;
  transition:background-color .2s ease,color .2s ease,box-shadow .2s ease;
}
.fb-cta::before{content:"";width:5px;height:5px;border-radius:50%;background:var(--ink);flex:0 0 auto}
.fb-cta:hover{background:transparent;color:var(--orange);text-decoration:none;box-shadow:0 0 0 1px var(--orange) inset}
.fb-cta:focus-visible{outline-color:var(--cyan)}

.fb-nav-toggle{
  display:none;align-items:center;gap:9px;
  padding:9px 12px;border:1px solid var(--line);border-radius:var(--radius);
  background:transparent;color:var(--text);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;cursor:pointer;
}
.fb-nav-toggle:hover{border-color:rgba(255,138,61,.6);color:var(--orange)}
.fb-nav-toggle__box{position:relative;display:block;width:16px;height:10px;flex:0 0 auto}
.fb-nav-toggle__box::before,
.fb-nav-toggle__box::after{
  content:"";position:absolute;left:0;right:0;height:1.5px;background:currentColor;
  transition:transform .22s ease,opacity .22s ease;
}
.fb-nav-toggle__box::before{top:0}
.fb-nav-toggle__box::after{bottom:0}
.fb-nav-toggle[aria-expanded="true"] .fb-nav-toggle__box::before{transform:translateY(4.25px) rotate(45deg)}
.fb-nav-toggle[aria-expanded="true"] .fb-nav-toggle__box::after{transform:translateY(-4.25px) rotate(-45deg)}
.fb-nav-toggle__label{line-height:1}

.fb-progress{
  position:absolute;left:0;right:0;bottom:-1px;height:2px;
  background:rgba(36,68,59,.55);overflow:hidden;pointer-events:none;
}
.fb-progress__bar{
  display:block;height:100%;width:0;
  background:linear-gradient(90deg,var(--cyan),var(--paper) 55%,var(--orange));
  transition:width .12s linear;
}

@keyframes fb-drop{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:none}}
@keyframes fb-fade{from{opacity:0;transform:translateY(4px)}to{opacity:1;transform:none}}

/* ---------- 页脚 ---------- */
.fb-footer{
  margin-top:clamp(56px,9vw,120px);
  border-top:1px solid var(--line);
  background-image:linear-gradient(180deg,rgba(12,42,36,.92),var(--ink) 60%);
  color:var(--text);
}
.fb-footer a{color:inherit;text-decoration:none}
.fb-footer__plate{
  position:relative;overflow:hidden;
  background:var(--paper);color:#122620;
  border-bottom:1px solid rgba(6,26,22,.28);
}
.fb-footer__plate::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:repeating-linear-gradient(135deg,rgba(6,26,22,.055) 0 2px,transparent 2px 9px);
}
.fb-plate{
  position:relative;z-index:1;
  display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;
  gap:16px 32px;padding-block:clamp(22px,3vw,34px);
}
.fb-plate__tag{
  flex:0 0 auto;
  padding:5px 10px;border:1px solid rgba(18,38,32,.5);border-radius:var(--radius);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;color:#122620;
}
.fb-plate__summary{
  flex:1 1 320px;max-width:52ch;
  font-size:15px;line-height:1.7;font-weight:500;color:#16302a;
}
.fb-plate__meta{
  flex:0 0 auto;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;color:rgba(18,38,32,.6);
}

.fb-footer__body{
  display:grid;
  grid-template-columns:minmax(230px,1.5fr) minmax(130px,.8fr) minmax(130px,.8fr) minmax(200px,1.15fr);
  gap:clamp(24px,3.4vw,52px);
  padding-block:clamp(34px,5vw,64px);
}
.fb-footer__brand{display:block}
.fb-footer__desc{
  margin-top:16px;max-width:34ch;
  font-size:14px;line-height:1.75;color:var(--muted);
}
.fb-footer__group{min-width:0}
.fb-footer__title{
  margin-bottom:14px;padding-bottom:10px;
  border-bottom:1px solid rgba(36,68,59,.9);
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.16em;color:var(--cyan);
}
.fb-footer__list{display:grid;gap:10px}
.fb-footer__link{
  display:inline-flex;align-items:center;gap:9px;
  font-size:14px;line-height:1.5;color:var(--muted);
  transition:color .18s ease;
}
.fb-footer__link::before{
  content:"";flex:0 0 auto;width:5px;height:1px;background:var(--line);
  transition:background-color .18s ease,width .18s ease;
}
.fb-footer__link:hover{color:var(--text);text-decoration:underline;text-underline-offset:3px}
.fb-footer__link:hover::before{background:var(--orange);width:12px}

.fb-footer__contact{display:grid;gap:9px}
.fb-contact__line{display:flex;gap:9px;font-size:13px;line-height:1.65;color:var(--muted);word-break:break-word}
.fb-contact__key{
  flex:0 0 auto;min-width:34px;padding-top:2px;
  font-family:var(--font-mono);font-size:10px;letter-spacing:.12em;color:var(--cyan);
}

.fb-footer__bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 24px;
  padding-block:20px;border-top:1px solid var(--line);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.06em;color:rgba(168,195,184,.78);
}
.fb-footer__legal{line-height:1.6}
.fb-footer__build{color:var(--orange);letter-spacing:.12em}

/* ---------- 平板 ---------- */
@media (max-width:1200px){
  .fb-command__link{padding:10px 9px;font-size:13px}
  .fb-command__index{font-size:9px}
  .fb-footer__body{grid-template-columns:minmax(200px,1.4fr) minmax(120px,1fr) minmax(120px,1fr);gap:clamp(20px,3vw,40px)}
  .fb-footer__group:last-child{grid-column:1 / -1}
  .fb-footer__contact{grid-template-columns:repeat(auto-fit,minmax(220px,1fr));display:grid}
}

/* ---------- 移动导航 + 小屏 ---------- */
@media (max-width:1023px){
  :root{--anchor-offset:112px}
  .fb-nav-toggle{display:inline-flex}
  .fb-status{display:none}
  .fb-header__actions{margin-left:auto}
  .fb-command{
    position:absolute;top:100%;left:0;right:0;z-index:90;
    margin-left:0;display:none;
    max-height:calc(100vh - 116px);overflow-y:auto;
    background:var(--ink-2);
    border-top:1px solid var(--line);
    border-bottom:1px solid var(--line);
    box-shadow:0 26px 50px -28px var(--ink-3);
  }
  .fb-command[data-open]{display:block;animation:fb-drop .24s ease both}
  .fb-command__list{flex-direction:column;align-items:stretch;gap:0;padding-block:6px}
  .fb-command__link{
    padding:14px 20px;font-size:15px;border-radius:0;
    border-bottom:1px solid rgba(36,68,59,.5);
  }
  .fb-command__link::after{
    left:0;right:auto;top:10px;bottom:10px;width:3px;height:auto;
    transform:scaleY(0);transform-origin:top;
  }
  .fb-command__link[aria-current="page"]::after{transform:scaleY(1)}
  .fb-command__link[aria-current="page"]{background:rgba(255,138,61,.08)}
  .fb-masthead{flex-wrap:wrap;gap:12px}
  .fb-footer__body{grid-template-columns:repeat(2,minmax(0,1fr))}
  .fb-footer__brand{grid-column:1 / -1}
  .fb-footer__group:last-child{grid-column:1 / -1}
  .fb-grid--split{grid-template-columns:minmax(0,1fr)}
}

@media (max-width:720px){
  body{font-size:16px}
  .fb-strip{font-size:10px;letter-spacing:.04em}
  .fb-strip__meta{display:none}
  .fb-brand__mark{width:34px;height:34px;font-size:12px}
  .fb-brand__name{font-size:18px}
  .fb-brand__desc{font-size:9px;letter-spacing:.1em}
  .fb-cta{padding:8px 12px;font-size:12px}
  .fb-nav-toggle{padding:8px 10px}
  .fb-footer__body{grid-template-columns:minmax(0,1fr);gap:28px}
  .fb-footer__group:last-child{grid-column:auto}
  .fb-footer__contact{grid-template-columns:minmax(0,1fr)}
  .fb-plate{gap:12px}
  .fb-plate__meta{width:100%}
  .fb-footer__bottom{font-size:10px;letter-spacing:.04em}
  .fb-btn{width:100%}
}

@media (max-width:420px){
  .fb-cta{display:none}
  .fb-nav-toggle{margin-left:auto}
}

/* ---------- 动效偏好 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .js-reveal [data-reveal]{opacity:1;transform:none}
  .fb-strip__dot{box-shadow:0 0 0 3px rgba(59,242,208,.16)}
}

/* ---------- 打印 ---------- */
@media print{
  .fb-header__strip,.fb-nav-toggle,.fb-progress,.fb-cta,.fb-skip,.fb-status{display:none !important}
  body{background:#fff;color:#000}
  .fb-panel,.fb-media{border-color:#999}
  .fb-footer{background:#fff;color:#000}
  .fb-footer__plate{background:#f0f0f0}
}