/* ============ reset ============ */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:104px}
body,h1,h2,h3,h4,p,ul,ol,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
table{border-collapse:collapse;width:100%}

/* ============ tokens ============ */
:root{
  --ink-void:#050A18;
  --ink-panel:#0B1430;
  --ink-layer:#16224A;
  --cyan:#22E3C0;
  --flame:#FF4B2B;
  --gold:#FFC857;
  --cold:#2E6BFF;
  --text:#EAF0FA;
  --text-dim:#94A3C4;
  --line:#24314F;
  --glass:rgba(14,23,48,.82);
  --rail-w:0px;
  --gutter:clamp(16px,4vw,40px);
  --radius:16px;
  --shadow-1:0 22px 44px -28px rgba(0,0,0,.9);
  --shadow-2:0 34px 70px -40px rgba(0,0,0,1);
  --font-sans:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-mono:ui-monospace,"SFMono-Regular","JetBrains Mono",Menlo,Consolas,"Liberation Mono",monospace;
  --ease:cubic-bezier(.22,.61,.36,1);
}
@media (min-width:1024px){:root{--rail-w:72px}}
@media (min-width:1320px){:root{--rail-w:96px}}

/* ============ base ============ */
body{
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.75;
  color:var(--text);
  background:var(--ink-void);
  padding-left:var(--rail-w);
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4{font-weight:800;letter-spacing:-.02em;line-height:1.18;font-style:normal}
h1{font-size:clamp(30px,4.6vw,56px)}
h2{font-size:clamp(24px,3.2vw,40px)}
h3{font-size:clamp(19px,2.2vw,28px)}
h4{font-size:clamp(16px,1.6vw,20px)}
strong{font-weight:800}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:4px}
::selection{background:rgba(34,227,192,.32);color:#04120F}
[data-section]{scroll-margin-top:104px}

/* ============ utilities ============ */
.shell{width:100%;max-width:1280px;margin-inline:auto;padding-inline:var(--gutter)}
.skip-link{
  position:fixed;left:12px;top:-70px;z-index:300;
  padding:10px 18px;border-radius:999px;
  background:var(--cyan);color:#04120F;
  font-size:13px;font-weight:800;letter-spacing:.04em;
  transition:top .2s var(--ease);
}
.skip-link:focus{top:12px}
.grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(16px,2vw,24px)}
@media (max-width:759px){.grid{grid-template-columns:repeat(6,minmax(0,1fr))}}

/* 章节标题组 */
.sec-head{display:flex;align-items:flex-end;gap:14px;margin-bottom:clamp(20px,3vw,32px)}
.sec-head__label{flex:0 0 auto;width:6px;height:34px;border-radius:2px;background:var(--cyan);box-shadow:0 0 16px rgba(34,227,192,.55)}
.sec-head__text{display:grid;gap:4px}
.sec-head__title{font-size:clamp(24px,3.2vw,40px)}
.sec-head__sub{font-size:13px;letter-spacing:.06em;color:var(--text-dim)}

/* 正文 */
.lede{font-size:clamp(16px,1.5vw,18px);line-height:1.8;color:var(--text-dim);max-width:40em}
.note{font-size:13px;line-height:1.7;color:var(--text-dim);max-width:48em;border-left:2px dashed var(--line);padding-left:12px}
.prose{font-size:16px;line-height:1.85}
.prose p{max-width:40em}
.prose p+p{margin-top:1.05em}
.prose a{color:var(--cyan);text-decoration:underline;text-underline-offset:3px}
.prose h2,.prose h3{margin-top:1.6em;margin-bottom:.6em}
.prose ul{display:grid;gap:8px;margin-top:.8em}
.prose li{position:relative;padding-left:18px;max-width:40em}
.prose li::before{content:"";position:absolute;left:0;top:.72em;width:6px;height:2px;background:var(--cyan)}
.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums}

/* 按钮 */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5em;
  padding:.72em 1.35em;border-radius:999px;
  font-size:14px;font-weight:800;letter-spacing:.02em;white-space:nowrap;
  border:1px solid transparent;text-decoration:none;
  transition:transform .2s var(--ease),box-shadow .2s var(--ease),background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.btn:hover{transform:translateY(-1px)}
.btn--primary{background:var(--cyan);color:#04120F;box-shadow:0 12px 26px -14px rgba(34,227,192,.9)}
.btn--primary:hover{box-shadow:0 16px 32px -14px rgba(34,227,192,1)}
.btn--ghost{border-color:var(--line);color:var(--text)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan)}
.btn--flame{background:var(--flame);color:#fff;box-shadow:0 12px 26px -14px rgba(255,75,43,.9)}

/* 标签 */
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 9px;border-radius:4px;
  border:1px dashed var(--line);
  font-size:12px;letter-spacing:.08em;line-height:1.5;
  color:var(--text-dim);text-decoration:none;
}
.tag--cyan{color:var(--cyan);border-color:rgba(34,227,192,.45)}
.tag--flame{color:var(--flame);border-color:rgba(255,75,43,.45)}
.tag--gold{color:var(--gold);border-color:rgba(255,200,87,.45)}

/* 面包屑 */
.crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:12px;letter-spacing:.04em;color:var(--text-dim)}
.crumbs__link{color:var(--text-dim);text-decoration:none;transition:color .2s var(--ease)}
.crumbs__link:hover{color:var(--cyan)}
.crumbs__sep{opacity:.45}
.crumbs__current{color:var(--text)}

/* 图片容器 */
.media{
  position:relative;display:block;overflow:hidden;isolation:isolate;
  border-radius:var(--radius);
  background:linear-gradient(135deg,var(--ink-layer),var(--ink-panel));
}
.media::before{content:"";display:block;padding-top:var(--media-ratio,62.5%)}
.media>img,.media>picture>img,.media>video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.media::after{
  content:"";position:absolute;inset:0;z-index:1;pointer-events:none;
  background:linear-gradient(180deg,rgba(5,10,24,0) 42%,rgba(5,10,24,.8));
}
.media--wide{--media-ratio:42%}
.media--square{--media-ratio:100%}
.media--tall{--media-ratio:128%}
.media__badge{position:absolute;left:14px;bottom:14px;z-index:2}

/* 叠层面板 */
.panel{
  position:relative;isolation:isolate;
  padding:clamp(18px,2.4vw,26px);
  border-radius:var(--radius);
  background:var(--ink-panel);
  box-shadow:var(--shadow-1);
}
.panel::before{
  content:"";position:absolute;inset:12px -12px -12px 12px;
  border-radius:var(--radius);background:var(--ink-layer);z-index:-1;
}
.panel--quiet{background:transparent;box-shadow:none}
.panel--quiet::before{display:none}

/* 数据件 */
.stat{display:grid;gap:6px}
.stat__num{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-weight:800;font-size:clamp(40px,7vw,88px);line-height:.92;
  letter-spacing:-.03em;color:var(--gold);
}
.stat__label{font-size:12px;letter-spacing:.14em;color:var(--text-dim)}
.display{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-weight:800;font-style:italic;
  font-size:clamp(56px,11vw,128px);line-height:.88;letter-spacing:-.04em;
  text-shadow:0 0 28px rgba(34,227,192,.4);
}

/* ============ header ============ */
.site-header{
  position:sticky;top:0;z-index:80;
  padding:10px var(--gutter) 12px;
  background:linear-gradient(180deg,rgba(5,10,24,.94),rgba(5,10,24,.6) 72%,rgba(5,10,24,0));
  transition:background .3s var(--ease);
}
.site-header[data-scrolled]{background:linear-gradient(180deg,rgba(5,10,24,.99),rgba(5,10,24,.88))}
.progress{position:absolute;left:0;right:0;top:0;height:2px;background:rgba(36,49,79,.55);overflow:hidden}
.progress__bar{
  display:block;height:100%;width:0;
  background:var(--cyan);box-shadow:0 0 14px rgba(34,227,192,.85);
  transition:width .12s linear;
}
.island{
  position:relative;
  display:flex;align-items:center;gap:12px;
  width:100%;max-width:1280px;margin-inline:auto;
  padding:8px 10px 8px 16px;
  border-radius:999px;
  border:1px dashed var(--line);
  background:var(--glass);
  -webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);
  box-shadow:var(--shadow-1);
  transition:border-color .3s var(--ease),box-shadow .3s var(--ease);
}
.site-header[data-scrolled] .island{border-color:rgba(34,227,192,.34);box-shadow:var(--shadow-2)}
.island__brand{display:inline-flex;align-items:center;gap:10px;flex:0 0 auto;padding-right:8px}
.island__mark{
  font-family:var(--font-mono);font-weight:800;font-size:20px;letter-spacing:-.05em;
  color:var(--cyan);text-shadow:0 0 18px rgba(34,227,192,.5);
}
.island__text{display:grid;line-height:1.15}
.island__name{font-size:17px;font-weight:800;letter-spacing:-.01em}
.island__sub{font-size:11px;letter-spacing:.1em;color:var(--text-dim)}

.nav-toggle{
  display:none;align-items:center;gap:9px;margin-left:auto;
  padding:9px 15px;border-radius:999px;
  border:1px dashed var(--line);
  font-size:13px;font-weight:800;letter-spacing:.08em;color:var(--text);
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle__bars{display:grid;gap:4px;width:16px}
.nav-toggle__bars i{display:block;height:2px;border-radius:2px;background:currentColor;transition:transform .24s var(--ease),opacity .2s var(--ease)}
.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)}

.nav{display:flex;align-items:center;gap:12px;margin-left:auto;min-width:0}
.nav__list{display:flex;align-items:center;gap:2px}
.nav__item{display:block}
.nav__link{
  display:inline-block;padding:8px 12px;border-radius:999px;
  font-size:14px;font-weight:700;letter-spacing:.01em;color:var(--text-dim);
  white-space:nowrap;
  transition:color .2s var(--ease),background .2s var(--ease),box-shadow .2s var(--ease);
}
.nav__link:hover{color:var(--text);background:rgba(34,227,192,.08)}
.nav__link[aria-current="page"],.nav__link.is-current{
  color:#04120F;background:var(--cyan);
  box-shadow:0 0 20px rgba(34,227,192,.4);
}
.nav__foot{display:flex;align-items:center;gap:12px;flex:0 0 auto}
.nav__stamp{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.04em;
  color:var(--text-dim);white-space:nowrap;
}
.nav__stamp time{color:var(--gold);font-variant-numeric:tabular-nums}

/* 侧边品牌轨道 */
.rail{display:none}
@media (min-width:1024px){
  .rail{
    position:fixed;left:0;top:0;bottom:0;width:var(--rail-w);z-index:70;
    display:flex;flex-direction:column;align-items:center;gap:18px;
    padding:18px 6px 20px;
    background:linear-gradient(180deg,var(--ink-panel) 0%,var(--ink-void) 62%);
    border-right:1px dashed var(--line);
  }
}
.rail__brand{
  display:flex;flex-direction:column;align-items:center;gap:12px;
  width:100%;padding:12px 0 14px;
  border-bottom:1px dashed var(--line);
}
.rail__mark{
  font-family:var(--font-mono);font-weight:800;font-size:16px;letter-spacing:.16em;
  writing-mode:vertical-rl;text-orientation:mixed;
  color:var(--cyan);text-shadow:0 0 16px rgba(34,227,192,.5);
}
.rail__word{
  writing-mode:vertical-rl;text-orientation:mixed;
  font-size:15px;font-weight:800;letter-spacing:.3em;color:var(--text);
}
.rail__dots{display:flex;flex-direction:column;align-items:center;gap:14px;margin:auto 0}
.rail__dot{
  position:relative;width:10px;height:10px;border-radius:50%;
  background:var(--line);padding:0;
  transition:height .24s var(--ease),background .24s var(--ease),box-shadow .24s var(--ease);
}
.rail__dot:hover{background:var(--text-dim)}
.rail__dot[data-active="true"]{
  height:24px;border-radius:6px;
  background:var(--cyan);box-shadow:0 0 14px rgba(34,227,192,.75);
}
.rail__dot::after{
  content:attr(data-label);
  position:absolute;left:20px;top:50%;
  transform:translateY(-50%) translateX(-6px);
  writing-mode:horizontal-tb;
  font-size:11px;letter-spacing:.14em;color:var(--text-dim);white-space:nowrap;
  opacity:0;pointer-events:none;
  transition:opacity .2s var(--ease),transform .2s var(--ease);
}
.rail__dot:hover::after,.rail__dot:focus-visible::after{opacity:1;transform:translateY(-50%)}
.rail__meta{display:flex;flex-direction:column;align-items:center;gap:10px;margin-top:auto}
.rail__sig,.rail__tag{
  writing-mode:vertical-rl;text-orientation:mixed;
  font-size:11px;letter-spacing:.24em;
}
.rail__sig{color:var(--text-dim)}
.rail__tag{color:var(--cyan);opacity:.82}

/* ============ footer ============ */
.site-footer{
  margin-top:clamp(64px,9vw,128px);
  border-top:1px dashed var(--line);
  background:linear-gradient(180deg,var(--ink-void),var(--ink-panel));
  padding-top:clamp(40px,6vw,72px);
}
.footer__grid{display:grid;gap:clamp(28px,4vw,48px);grid-template-columns:1fr}
@media (min-width:760px){.footer__grid{grid-template-columns:1.1fr .9fr}}
@media (min-width:1080px){.footer__grid{grid-template-columns:1.3fr 1.5fr 1fr;align-items:start}}

.footer__brand{display:grid;gap:12px;align-content:start}
.footer__logo{
  font-size:24px;font-weight:800;letter-spacing:-.02em;
  color:var(--text);text-shadow:0 0 22px rgba(34,227,192,.28);
}
.footer__line{
  font-size:12px;letter-spacing:.16em;color:var(--cyan);
  border-top:1px dashed var(--line);padding-top:10px;
}
.footer__summary{font-size:14px;line-height:1.8;color:var(--text-dim);max-width:36em}
.footer__fine{font-size:12px;line-height:1.7;color:var(--text-dim);opacity:.8;max-width:38em}

.footer__cols{display:grid;gap:24px;grid-template-columns:repeat(auto-fit,minmax(130px,1fr))}
.footer__col{display:grid;gap:12px;align-content:start}
.footer__title{
  display:flex;align-items:center;gap:8px;
  font-size:12px;font-weight:800;letter-spacing:.2em;color:var(--cyan);
}
.footer__title::before{content:"";width:6px;height:6px;border-radius:1px;background:var(--flame)}
.footer__list{display:grid;gap:10px}
.footer__link{
  font-size:14px;color:var(--text-dim);
  transition:color .2s var(--ease);
}
.footer__link:hover{color:var(--cyan)}

.footer__contact{display:grid;gap:16px;align-content:start}
.footer__contact-item{display:grid;gap:3px}
.footer__label{font-size:11px;letter-spacing:.18em;color:var(--text-dim)}
.footer__value{font-family:var(--font-mono);font-size:14px;color:var(--text);word-break:break-all}
.footer__note{font-size:12px;line-height:1.7;color:var(--text-dim);opacity:.85;max-width:34em}
.copy-btn{
  justify-self:start;
  display:inline-flex;align-items:center;gap:6px;
  margin-top:5px;padding:5px 11px;border-radius:999px;
  border:1px dashed var(--line);
  font-size:11px;letter-spacing:.1em;color:var(--text-dim);
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.copy-btn:hover{color:var(--cyan);border-color:rgba(34,227,192,.55)}
.copy-btn[data-copied="true"]{color:var(--cyan);border-color:var(--cyan)}

.footer__base{
  margin-top:clamp(32px,5vw,56px);
  border-top:1px dashed var(--line);
  background:rgba(5,10,24,.6);
}
.footer__base-inner{
  display:flex;flex-wrap:wrap;gap:8px 24px;justify-content:space-between;
  padding:18px 0;font-size:12px;letter-spacing:.04em;color:var(--text-dim);
}
.footer__base-inner span:first-child{color:var(--text)}

/* ============ 动效 ============ */
html.js [data-reveal]{
  opacity:0;transform:translateY(12px);
  transition:opacity .24s var(--ease),transform .24s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
}
html.js [data-reveal].is-in{opacity:1;transform:none}
@keyframes nav-in{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:none}}

/* ============ 移动端导航 ============ */
@media (max-width:960px){
  .island{padding:8px 10px;border-radius:22px}
  .island__sub{display:none}
  .nav-toggle{display:inline-flex}
  .nav{
    position:absolute;left:0;right:0;top:calc(100% + 10px);
    display:none;flex-direction:column;align-items:stretch;gap:10px;
    margin-left:0;padding:14px;border-radius:20px;
    border:1px dashed var(--line);
    background:rgba(11,20,48,.97);
    -webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);
    box-shadow:var(--shadow-2);
  }
  .nav[data-open]{display:flex;animation:nav-in .24s var(--ease)}
  .nav__list{flex-direction:column;align-items:stretch;gap:4px}
  .nav__link{padding:11px 14px;border-radius:12px;font-size:15px}
  .nav__foot{
    flex-direction:column;align-items:stretch;gap:10px;
    border-top:1px dashed var(--line);padding-top:12px;
  }
  .nav__foot .btn{width:100%}
  .nav__stamp{text-align:center}
}
@media (min-width:961px) and (max-width:1180px){
  .nav__link{padding:8px 9px;font-size:13px}
  .island__sub{display:none}
}

/* ============ 无障碍与降级 ============ */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  html.js [data-reveal]{opacity:1;transform:none}
  .progress__bar{transition:none}
}