/* ===== 0. Reset ===== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,p,figure,blockquote,dl,dd,address{margin:0}
ul,ol{margin:0;padding:0}
img,svg{max-width:100%}
button{font:inherit;color:inherit}

/* ===== 1. Tokens ===== */
:root{
  --ink:#07111F;
  --console:#0D1F33;
  --deep-teal:#0B2B33;
  --cyan:#4DE3E0;
  --ice:#A8F7F4;
  --gold:#F6C453;
  --amber:#FFD98A;
  --coral:#FF6B5E;
  --wine:#4A1F3D;
  --paper:#E9F2F5;
  --line:#27445A;
  --shell-max:1240px;
  --pad:clamp(16px,3vw,32px);
  --font-display:"MiSans","Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-body:"Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"JetBrains Mono","Cascadia Code","SFMono-Regular",ui-monospace,Consolas,monospace;
  --ease:cubic-bezier(.22,.61,.36,1);
  --fast:180ms;
  --chamfer-btn:polygon(0 0,calc(100% - 12px) 0,100% 12px,100% 100%,12px 100%,0 calc(100% - 12px));
  --chamfer-panel:polygon(0 0,calc(100% - 22px) 0,100% 22px,100% 100%,22px 100%,0 calc(100% - 22px));
}

/* ===== 2. Base / 中文排版 ===== */
body{
  margin:0;
  min-height:100vh;
  background-color:var(--ink);
  background-image:
    radial-gradient(900px 420px at 84% -10%,rgba(77,227,224,.14),transparent 70%),
    radial-gradient(760px 380px at 2% 4%,rgba(246,196,83,.09),transparent 72%);
  background-repeat:no-repeat;
  color:var(--paper);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:900;line-height:1.15;letter-spacing:-.03em}
a{color:var(--cyan)}
a:hover{color:var(--ice)}
::selection{background:rgba(246,196,83,.32);color:#fff}
:focus-visible{outline:3px solid var(--cyan);outline-offset:2px}
#main-content{scroll-margin-top:150px}

/* ===== 3. Utilities ===== */
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.shell{width:100%;max-width:var(--shell-max);margin-inline:auto;padding-inline:var(--pad)}
.page-main{display:block;padding-block:clamp(20px,4vw,44px) clamp(40px,7vw,88px)}
.mono{font-family:var(--font-mono);font-size:13px;letter-spacing:.02em;font-variant-numeric:tabular-nums}
.label{display:inline-block;font-family:var(--font-mono);font-size:12px;letter-spacing:.14em;color:var(--cyan);text-transform:uppercase}
.eyebrow{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-mono);font-size:12px;letter-spacing:.16em;color:var(--cyan)}
.eyebrow::before{content:"";width:24px;height:2px;background:var(--gold);flex:0 0 auto}
.lede{max-width:68ch;font-size:clamp(15px,1.5vw,17px);color:rgba(233,242,245,.78)}
.divider{height:1px;border:0;margin:clamp(22px,4vw,40px) 0;background:linear-gradient(90deg,var(--line),rgba(39,68,90,.15) 60%,transparent)}
.skip-link{
  position:fixed;top:-70px;left:16px;z-index:120;
  padding:10px 18px;background:var(--cyan);color:#04121B;
  font-weight:800;font-size:14px;letter-spacing:.04em;text-decoration:none;
  clip-path:var(--chamfer-btn);transition:top var(--fast) var(--ease);
}
.skip-link:focus{top:12px;color:#04121B}

/* ===== 4. Header ===== */
.site-header{
  position:sticky;top:0;z-index:60;
  isolation:isolate;
  color:var(--paper);
  background:linear-gradient(180deg,rgba(13,31,51,.985),rgba(7,17,31,.965));
  border-bottom:1px solid var(--line);
  box-shadow:0 10px 34px rgba(3,9,17,.55);
}
.site-header::before{
  content:"";position:absolute;inset:0;z-index:-1;pointer-events:none;
  background-image:linear-gradient(90deg,rgba(77,227,224,.055) 0 1px,transparent 1px 100%);
  background-size:68px 100%;
  opacity:.55;
}
.header-signal{
  height:3px;
  background:
    linear-gradient(90deg,var(--cyan) 0 22%,var(--gold) 22% 29%,rgba(255,107,94,.7) 29% 32%,transparent 32% 100%);
}
.header-shell{
  width:100%;max-width:var(--shell-max);margin-inline:auto;padding-inline:var(--pad);
}
.header-top{
  display:flex;align-items:center;justify-content:space-between;gap:clamp(12px,3vw,32px);
  flex-wrap:wrap;padding:14px 0 11px;
  border-bottom:1px dashed rgba(39,68,90,.75);
}
.brand{
  display:inline-flex;align-items:center;gap:12px;
  text-decoration:none;color:var(--paper);
  transition:color var(--fast) var(--ease);
}
.brand:hover{color:var(--ice)}
.brand-mark{
  position:relative;flex:0 0 auto;
  width:36px;height:36px;display:grid;place-items:center;
  background:linear-gradient(135deg,rgba(77,227,224,.22),rgba(246,196,83,.14));
  border:1px solid rgba(77,227,224,.55);
  clip-path:polygon(0 0,70% 0,100% 30%,100% 100%,30% 100%,0 70%);
}
.brand-mark-core{
  width:11px;height:11px;background:var(--gold);
  border-radius:2px;transform:rotate(45deg);
  box-shadow:0 0 12px rgba(246,196,83,.85);
}
.brand-text{display:block;min-width:0}
.brand-name{
  display:block;font-family:var(--font-display);
  font-size:clamp(17px,2.2vw,21px);font-weight:900;letter-spacing:-.035em;line-height:1.2;
}
.brand-line{
  display:block;margin-top:2px;
  font-size:11.5px;letter-spacing:.13em;color:rgba(233,242,245,.6);
}
.header-utility{display:flex;align-items:center;gap:clamp(10px,2vw,22px);flex-wrap:wrap}
.utility-note{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.06em;
  color:rgba(233,242,245,.66);
}
.status-dot{
  width:7px;height:7px;border-radius:50%;background:var(--cyan);
  box-shadow:0 0 0 3px rgba(77,227,224,.16);
  animation:dot-pulse 2.6s var(--ease) infinite;
}
@keyframes dot-pulse{
  0%,100%{box-shadow:0 0 0 3px rgba(77,227,224,.16)}
  50%{box-shadow:0 0 0 6px rgba(77,227,224,.05)}
}
.quick-keys{display:flex;flex-wrap:wrap;gap:8px;list-style:none}
.key-chip{
  display:inline-flex;align-items:center;gap:8px;
  padding:7px 13px 7px 10px;
  font-size:13px;font-weight:700;letter-spacing:.02em;text-decoration:none;
  color:var(--paper);
  background:rgba(77,227,224,.09);
  border:1px solid rgba(77,227,224,.38);
  clip-path:var(--chamfer-btn);
  transition:background-color var(--fast) var(--ease),border-color var(--fast) var(--ease),color var(--fast) var(--ease);
}
.key-chip:hover{background:rgba(77,227,224,.2);border-color:var(--cyan);color:#fff}
.key-chip:focus-visible{outline:3px solid var(--cyan);outline-offset:-3px;background:rgba(77,227,224,.22)}
.key-index{
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.08em;
  color:var(--cyan);transition:color var(--fast) var(--ease);
}
.key-chip:hover .key-index{color:var(--gold)}

.header-bar{
  display:flex;align-items:center;justify-content:space-between;gap:14px;
  flex-wrap:wrap;padding:2px 0 0;
}
.site-nav{display:flex;flex:1 1 auto;min-width:0}
.nav-list{
  display:flex;flex-wrap:wrap;align-items:center;
  gap:clamp(4px,1.8vw,26px);
  list-style:none;counter-reset:nav;
}
.nav-link{
  position:relative;display:inline-flex;align-items:baseline;gap:8px;
  padding:14px 2px;text-decoration:none;
  font-size:15px;font-weight:600;letter-spacing:.01em;
  color:rgba(233,242,245,.78);
  transition:color var(--fast) var(--ease);
  counter-increment:nav;
}
.nav-link::before{
  content:counter(nav,decimal-leading-zero);
  font-family:var(--font-mono);font-size:10px;letter-spacing:.06em;
  color:rgba(77,227,224,.55);
  transition:color var(--fast) var(--ease);
}
.nav-link::after{
  content:"";position:absolute;left:0;right:0;bottom:5px;height:2px;
  background:linear-gradient(90deg,var(--cyan),rgba(77,227,224,.08));
  transform:scaleX(0);transform-origin:left center;
  transition:transform var(--fast) var(--ease);
}
.nav-link:hover,.nav-link:focus-visible{color:#fff}
.nav-link:hover::before,.nav-link:focus-visible::before{color:var(--gold)}
.nav-link:hover::after,.nav-link:focus-visible::after{transform:scaleX(1)}
.nav-link:focus-visible{outline:3px solid var(--cyan);outline-offset:-2px}
.nav-link[aria-current="page"]{color:var(--ice)}
.nav-link[aria-current="page"]::before{color:var(--gold)}
.nav-link[aria-current="page"]::after{
  transform:scaleX(1);
  box-shadow:0 0 12px rgba(77,227,224,.7);
}
.nav-toggle{
  display:none;align-items:center;gap:10px;
  padding:10px 15px;cursor:pointer;
  font-size:13px;font-weight:700;letter-spacing:.1em;
  color:var(--paper);
  background:rgba(77,227,224,.09);
  border:1px solid rgba(77,227,224,.42);
  clip-path:var(--chamfer-btn);
  transition:background-color var(--fast) var(--ease),border-color var(--fast) var(--ease);
}
.nav-toggle:hover{background:rgba(77,227,224,.2);border-color:var(--cyan)}
.nav-toggle:focus-visible{outline:3px solid var(--cyan);outline-offset:-3px}
.nav-toggle-bars{display:inline-flex;flex-direction:column;justify-content:space-between;width:16px;height:12px}
.nav-toggle-bars span{
  display:block;height:2px;width:100%;background:var(--cyan);
  transition:transform var(--fast) var(--ease),opacity var(--fast) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(1){transform:translateY(5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(3){transform:translateY(-5px) rotate(-45deg)}

/* ===== 5. Footer ===== */
.site-footer{
  position:relative;
  margin-top:clamp(36px,6vw,84px);
  color:var(--paper);
  background:linear-gradient(180deg,var(--console) 0%,#0A1725 55%,var(--ink) 100%);
  border-top:1px solid var(--line);
  overflow:hidden;
}
.footer-rail{
  height:12px;
  background:repeating-linear-gradient(115deg,rgba(77,227,224,.55) 0 2px,transparent 2px 14px);
  opacity:.5;
  border-bottom:1px solid rgba(39,68,90,.8);
}
.footer-shell{
  width:100%;max-width:var(--shell-max);margin-inline:auto;
  padding:clamp(30px,5vw,56px) var(--pad) 0;
}
.footer-top{
  display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,1fr);
  gap:clamp(16px,3vw,32px);align-items:end;
  padding-bottom:26px;border-bottom:1px solid var(--line);
}
.footer-brand{min-width:0}
.footer-brand-name{
  display:block;font-family:var(--font-display);
  font-size:clamp(22px,3.2vw,32px);font-weight:900;letter-spacing:-.04em;line-height:1.1;
}
.footer-brand-line{
  margin-top:8px;font-size:13px;letter-spacing:.1em;
  color:rgba(233,242,245,.62);
}
.footer-keys{display:flex;flex-wrap:wrap;gap:8px;justify-content:flex-end;list-style:none}
.footer-key{
  display:inline-flex;align-items:center;
  padding:8px 14px;text-decoration:none;
  font-size:13px;font-weight:700;letter-spacing:.02em;
  color:var(--amber);
  background:rgba(246,196,83,.1);
  border:1px solid rgba(246,196,83,.42);
  clip-path:var(--chamfer-btn);
  transition:background-color var(--fast) var(--ease),color var(--fast) var(--ease),border-color var(--fast) var(--ease),transform var(--fast) var(--ease);
}
.footer-key:hover{
  color:#04121B;background:var(--gold);border-color:var(--gold);transform:translateY(-2px);
}
.footer-key:focus-visible{outline:3px solid var(--cyan);outline-offset:-3px}
.footer-grid{
  display:grid;grid-template-columns:minmax(0,.8fr) minmax(0,.8fr) minmax(0,1.5fr);
  gap:clamp(20px,3.5vw,40px);
  padding:clamp(24px,4vw,38px) 0;
}
.footer-col{min-width:0}
.footer-col-title{
  margin-bottom:14px;
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.18em;color:var(--cyan);
}
.footer-links{list-style:none;display:grid;gap:10px}
.footer-link{
  display:inline-flex;align-items:center;gap:8px;
  font-size:14px;text-decoration:none;color:rgba(233,242,245,.8);
  transition:color var(--fast) var(--ease);
}
.footer-link::before{
  content:"";width:0;height:1px;background:var(--gold);
  transition:width var(--fast) var(--ease);
}
.footer-link:hover,.footer-link:focus-visible{color:var(--ice)}
.footer-link:hover::before,.footer-link:focus-visible::before{width:14px}
.footer-contact{display:grid;gap:12px;font-style:normal}
.contact-row{
  display:grid;grid-template-columns:44px minmax(0,1fr) auto;
  gap:10px;align-items:baseline;
}
.contact-label{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;
  color:rgba(77,227,224,.8);
}
.contact-value{
  font-family:var(--font-mono);font-size:12.5px;letter-spacing:.01em;
  color:var(--paper);word-break:break-word;
}
.copy-btn{
  padding:4px 10px;cursor:pointer;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;
  color:var(--gold);
  background:rgba(246,196,83,.1);
  border:1px solid rgba(246,196,83,.45);
  clip-path:var(--chamfer-btn);
  transition:background-color var(--fast) var(--ease),color var(--fast) var(--ease),border-color var(--fast) var(--ease);
}
.copy-btn:hover{background:rgba(246,196,83,.22);border-color:var(--gold);color:var(--amber)}
.copy-btn:focus-visible{outline:3px solid var(--cyan);outline-offset:-3px}
.copy-btn[data-copied="true"]{color:#04121B;background:var(--gold);border-color:var(--gold)}
.copy-btn[data-copied="false"]{color:#FFD3CE;background:rgba(255,107,94,.16);border-color:rgba(255,107,94,.6)}
.contact-note{
  margin-top:14px;padding-top:12px;
  border-top:1px dashed rgba(39,68,90,.8);
  font-size:12.5px;line-height:1.7;color:rgba(233,242,245,.6);
}
.footer-legal{
  display:flex;flex-wrap:wrap;gap:12px;justify-content:space-between;align-items:center;
  padding:16px 0 26px;border-top:1px solid var(--line);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.04em;
  color:rgba(233,242,245,.6);
}
.legal-icp{color:rgba(233,242,245,.72)}
.legal-copyright{font-variant-numeric:tabular-nums}

/* ===== 6. Shared page components ===== */
.breadcrumbs{padding-block:2px 0}
.breadcrumbs ol{display:flex;flex-wrap:wrap;align-items:center;gap:8px;list-style:none;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.04em;color:rgba(233,242,245,.58)}
.breadcrumbs li{display:flex;align-items:center;gap:8px}
.breadcrumbs li+li::before{content:"/";color:var(--line)}
.breadcrumbs a{color:rgba(233,242,245,.75);text-decoration:none}
.breadcrumbs a:hover{color:var(--cyan)}

.section{padding-block:clamp(24px,4.5vw,52px)}
.section-head{display:grid;gap:12px;padding-top:18px;margin-bottom:clamp(18px,3vw,30px);border-top:1px solid var(--line)}
.section-title{font-size:clamp(26px,4.2vw,46px);letter-spacing:-.04em;margin:0}
.section-title .mono{color:var(--cyan);font-weight:400}

.panel{
  position:relative;
  padding:clamp(18px,3vw,30px);
  background:linear-gradient(160deg,rgba(13,31,51,.97),rgba(7,17,31,.97));
  border:1px solid var(--line);
  clip-path:var(--chamfer-panel);
}
.panel--teal{
  background:linear-gradient(160deg,rgba(11,43,51,.98),rgba(7,17,31,.97));
  border-color:rgba(77,227,224,.3);
}
.panel--wine{
  background:linear-gradient(160deg,rgba(74,31,61,.95),rgba(7,17,31,.97));
  border-color:rgba(246,196,83,.3);
}

.btn{
  display:inline-flex;align-items:center;gap:10px;
  padding:12px 20px;cursor:pointer;text-decoration:none;
  font-size:15px;font-weight:700;letter-spacing:.02em;
  color:var(--paper);
  background:rgba(233,242,245,.05);
  border:1px solid var(--line);
  clip-path:var(--chamfer-btn);
  transition:background-color var(--fast) var(--ease),border-color var(--fast) var(--ease),color var(--fast) var(--ease),transform var(--fast) var(--ease);
}
.btn:hover{transform:translateY(-2px);border-color:var(--cyan);background:rgba(77,227,224,.16);color:var(--ice)}
.btn:focus-visible{outline:3px solid var(--cyan);outline-offset:-3px}
.btn--primary{
  color:#04121B;border-color:transparent;
  background:linear-gradient(120deg,var(--cyan),#33BEBC);
}
.btn--primary:hover{color:#04121B;background:linear-gradient(120deg,var(--ice),var(--cyan));border-color:transparent}
.btn--gold{color:var(--gold);border-color:rgba(246,196,83,.6);background:rgba(246,196,83,.1)}
.btn--gold:hover{color:#04121B;background:var(--gold);border-color:var(--gold)}
.btn--ghost{background:transparent}

.badge{
  display:inline-flex;align-items:center;gap:6px;
  padding:3px 10px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  color:var(--ice);background:rgba(77,227,224,.1);
  border:1px solid rgba(77,227,224,.42);
  clip-path:polygon(0 0,calc(100% - 8px) 0,100% 8px,100% 100%,8px 100%,0 calc(100% - 8px));
}
.badge--gold{color:var(--amber);background:rgba(246,196,83,.12);border-color:rgba(246,196,83,.55)}
.badge--coral{color:#FFD3CE;background:rgba(255,107,94,.14);border-color:rgba(255,107,94,.55)}

.media-frame{
  position:relative;display:block;overflow:hidden;
  aspect-ratio:16/9;
  background:linear-gradient(150deg,rgba(13,31,51,.95),rgba(11,43,51,.95));
  border:1px solid var(--line);
  clip-path:polygon(0 0,calc(100% - 18px) 0,100% 18px,100% 100%,18px 100%,0 calc(100% - 18px));
}
.media-frame img{display:block;width:100%;height:100%;object-fit:cover}
.media-frame--wide{aspect-ratio:21/9}
.media-frame--square{aspect-ratio:1/1}
.media-frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:linear-gradient(180deg,rgba(7,17,31,0) 55%,rgba(7,17,31,.72));
}

/* JS 注入：阅读进度 */
.scroll-progress{
  position:fixed;top:0;left:0;right:0;height:3px;z-index:110;
  background:rgba(7,17,31,.55);pointer-events:none;
}
.scroll-progress-bar{
  display:block;height:100%;width:100%;
  transform:scaleX(0);transform-origin:left center;
  background:linear-gradient(90deg,var(--cyan),var(--gold));
  box-shadow:0 0 12px rgba(77,227,224,.55);
}

/* 显现（仅 JS 可用时隐藏初始态） */
html.js [data-reveal]{
  opacity:0;transform:translateY(10px);
  transition:opacity 380ms var(--ease),transform 380ms var(--ease);
}
html.js [data-reveal].is-visible{opacity:1;transform:none}

/* ===== 7. Responsive ===== */
@media (max-width:1080px){
  .footer-grid{grid-template-columns:minmax(0,1fr) minmax(0,1fr)}
  .footer-col--contact{grid-column:1 / -1}
}
@media (max-width:900px){
  body{font-size:16px}
  .header-top{flex-direction:column;align-items:flex-start;gap:12px}
  .header-utility{width:100%;justify-content:space-between}
  .header-bar{justify-content:space-between}
  .nav-toggle{display:inline-flex;order:1;margin-left:auto}
  .site-nav{
    order:2;display:none;width:100%;
    padding:6px 0 14px;border-top:1px solid rgba(39,68,90,.7);margin-top:6px;
  }
  .site-nav[data-open="true"]{display:block;animation:nav-in 180ms var(--ease)}
  .site-nav[data-open="false"]{display:none}
  @keyframes nav-in{from{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:none}}
  .nav-list{flex-direction:column;align-items:stretch;gap:0}
  .nav-link{
    display:flex;width:100%;padding:13px 6px;
    font-size:16px;border-bottom:1px solid rgba(39,68,90,.55);
  }
  .nav-link::after{display:none}
  .nav-link[aria-current="page"]{
    color:var(--ice);
    background:linear-gradient(90deg,rgba(77,227,224,.16),rgba(77,227,224,0) 78%);
    box-shadow:inset 3px 0 0 var(--cyan);
  }
  .nav-link[aria-current="page"]::before{color:var(--gold)}
  .footer-top{grid-template-columns:1fr;align-items:start}
  .footer-keys{justify-content:flex-start}
}
@media (max-width:640px){
  .utility-note{display:none}
  .quick-keys{width:100%}
  .key-chip{flex:1 1 auto;justify-content:center}
  .footer-grid{grid-template-columns:1fr;gap:26px}
  .contact-row{grid-template-columns:40px minmax(0,1fr) auto}
  .footer-legal{flex-direction:column;align-items:flex-start;gap:6px}
  .brand-line{letter-spacing:.08em}
}

/* ===== 8. Reduced motion ===== */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  html.js [data-reveal]{opacity:1;transform:none}
  .btn:hover,.footer-key:hover{transform:none}
}