/* =========================================================
   /assets/site.css — 博狗在线主页 共享外壳
   坐标帧体系：深空蓝底 / 霓虹青锚点 / 琥珀橙告警
   ========================================================= */

/* ---------- 1. 变量 ---------- */
:root{
  --ink:#0B1220;
  --ink-layer:#131C2E;
  --anchor:#05080F;
  --cyan:#33E1E1;
  --cyan-dim:#1A8F92;
  --amber:#FF9A2E;
  --white:#F2F6FF;
  --mist:#8A9BB5;
  --noise:#2A3548;
  --scan:#0E3B3F;

  --hair:rgba(138,155,181,.2);
  --hair-strong:rgba(138,155,181,.34);
  --hair-cyan:rgba(51,225,225,.34);
  --hair-amber:rgba(255,154,46,.4);

  --font-mono:ui-monospace,"SFMono-Regular","JetBrains Mono",Menlo,Consolas,"Noto Sans Mono CJK SC","Courier New",monospace;
  --font-body:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;

  --shell:1280px;
  --gap:clamp(16px,2.4vw,32px);
  --pad-inline:clamp(16px,3vw,32px);
  --cut:16px;
}

/* ---------- 2. Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:124px;
}
body,h1,h2,h3,h4,h5,p,figure,blockquote,dl,dd,ul,ol{margin:0}
ul,ol{list-style:none;padding:0}
img,svg,video{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0}
table{border-collapse:collapse;width:100%}

/* ---------- 3. 基础排版 ---------- */
body{
  min-height:100vh;
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  color:var(--white);
  background-color:var(--ink);
  background-image:
    linear-gradient(rgba(51,225,225,.045) 1px,transparent 1px),
    linear-gradient(90deg,rgba(51,225,225,.045) 1px,transparent 1px);
  background-size:72px 72px;
}

h1,h2,h3,h4,.eyebrow,.tab,.footer-title,.btn{
  font-family:var(--font-mono);
  letter-spacing:.06em;
}
h1,h2,h3,h4{font-weight:600;line-height:1.24}
h1{font-size:clamp(2.75rem,4.6vw,4rem);letter-spacing:.08em}
h2{font-size:clamp(1.55rem,2.6vw,2.1rem);letter-spacing:.07em}
h3{font-size:1.2rem;letter-spacing:.06em}
h4{font-size:1rem;letter-spacing:.06em}

::selection{background:var(--cyan);color:var(--anchor)}

:focus-visible{
  outline:2px solid var(--cyan);
  outline-offset:3px;
  border-radius:2px;
}

/* ---------- 4. 工具类 ---------- */
.sr-only{
  position:absolute;
  width:1px;height:1px;
  padding:0;margin:-1px;
  overflow:hidden;
  clip:rect(0 0 0 0);
  clip-path:inset(50%);
  white-space:nowrap;
  border:0;
}

.container{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--pad-inline);
}

.site-main{display:block;padding-bottom:clamp(48px,6vw,96px)}

.stack > * + *{margin-top:var(--gap)}

.rule{
  height:1px;
  border:0;
  margin:var(--gap) 0;
  background:linear-gradient(90deg,var(--cyan-dim),rgba(51,225,225,.06) 60%,transparent);
}

.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:8px 20px;
  padding-bottom:14px;
  margin-bottom:var(--gap);
  border-bottom:1px solid var(--hair);
}

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-size:12px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--cyan);
}
.eyebrow::before{
  content:"";
  width:22px;
  height:1px;
  background:var(--cyan);
}

.tag-row{display:flex;flex-wrap:wrap;gap:8px}

/* ---------- 5. 通用组件 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 22px;
  font-size:13.5px;
  letter-spacing:.1em;
  color:var(--white);
  border:1px solid var(--hair-cyan);
  background:rgba(19,28,46,.6);
  cursor:pointer;
  clip-path:polygon(0 0,calc(100% - 12px) 0,100% 12px,100% 100%,12px 100%,0 calc(100% - 12px));
  transition:background-color .2s ease,color .2s ease,transform .2s ease,border-color .2s ease;
}
.btn:hover{
  background:rgba(51,225,225,.14);
  border-color:var(--cyan);
  transform:translateY(-2px);
}
.btn--primary{
  background:var(--cyan);
  color:var(--anchor);
  border-color:var(--cyan);
}
.btn--primary:hover{background:#5df0f0;color:var(--anchor)}
.btn--ghost{
  background:transparent;
  color:var(--mist);
}
.btn--ghost:hover{color:var(--cyan);background:rgba(51,225,225,.08)}

.panel{
  position:relative;
  background:var(--ink-layer);
  border:1px solid var(--hair);
  padding:clamp(18px,2.2vw,26px);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
  transition:border-color .2s ease,transform .2s ease,background-color .2s ease;
}
.panel:hover{
  border-color:var(--hair-cyan);
  transform:translateY(-2px);
}

.chip{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--cyan);
  background:rgba(51,225,225,.08);
  border:1px solid var(--hair-cyan);
}
.chip--amber{
  color:var(--amber);
  background:rgba(255,154,46,.1);
  border-color:var(--hair-amber);
}
.chip--muted{
  color:var(--mist);
  background:rgba(42,53,72,.5);
  border-color:var(--hair);
}

.code-chip{
  display:inline-block;
  padding:3px 9px;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.12em;
  color:var(--amber);
  background:rgba(255,154,46,.1);
  border:1px solid var(--hair-amber);
}

.copy-field{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
  padding:9px 10px 9px 12px;
  font-family:var(--font-mono);
  font-size:13px;
  color:var(--white);
  background:var(--anchor);
  border:1px solid var(--hair);
  border-left:2px solid var(--cyan-dim);
}
.copy-btn{
  margin-left:auto;
  padding:5px 10px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.1em;
  color:var(--mist);
  border:1px solid var(--hair-cyan);
  background:transparent;
  cursor:pointer;
  transition:color .18s ease,background-color .18s ease,border-color .18s ease;
}
.copy-btn:hover{color:var(--cyan);border-color:var(--cyan)}
.copy-btn[data-copied="true"]{
  color:var(--anchor);
  background:var(--cyan);
  border-color:var(--cyan);
}

.breadcrumb{
  padding:14px 0;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.08em;
  color:var(--mist);
}
.breadcrumb-list{display:flex;flex-wrap:wrap;align-items:center;gap:8px}
.breadcrumb-item{display:inline-flex;align-items:center;gap:8px}
.breadcrumb-item + .breadcrumb-item::before{
  content:"/";
  color:var(--cyan-dim);
}
.breadcrumb-link{color:var(--mist);transition:color .18s ease}
.breadcrumb-link:hover{color:var(--cyan)}
.breadcrumb-item[aria-current="page"]{color:var(--white)}

.prose{max-width:42rem;font-size:16px;line-height:1.75;color:var(--white)}
.prose > * + *{margin-top:1.05em}
.prose h2{margin-top:1.8em;font-size:1.4rem}
.prose h3{margin-top:1.5em;font-size:1.1rem;color:var(--cyan)}
.prose ul{padding-left:1.2em;list-style:none}
.prose ul li{position:relative;padding-left:16px}
.prose ul li::before{
  content:"";
  position:absolute;
  left:0;top:.72em;
  width:8px;height:1px;
  background:var(--cyan);
}
.prose a{color:var(--cyan);border-bottom:1px solid var(--hair-cyan)}
.prose a:hover{border-bottom-color:var(--cyan)}
.prose strong{color:var(--white);font-weight:600}
.prose code{
  font-family:var(--font-mono);
  font-size:.86em;
  padding:2px 6px;
  color:var(--amber);
  background:rgba(255,154,46,.1);
}

.media-frame{
  position:relative;
  display:block;
  overflow:hidden;
  background:
    linear-gradient(135deg,rgba(19,28,46,1),rgba(5,8,15,1));
  border:1px solid var(--hair);
}
.media-frame::before{
  content:"";
  position:absolute;
  inset:0;
  z-index:2;
  pointer-events:none;
  background-image:repeating-linear-gradient(0deg,rgba(51,225,225,.09) 0 1px,transparent 1px 5px);
  opacity:.5;
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  z-index:1;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(51,225,225,.07) 1px,transparent 1px),
    linear-gradient(90deg,rgba(51,225,225,.07) 1px,transparent 1px);
  background-size:32px 32px;
}
.media-frame img{
  position:relative;
  z-index:0;
  width:100%;
  height:100%;
  object-fit:cover;
}
.media-frame--16x9{aspect-ratio:16/9}
.media-frame--4x3{aspect-ratio:4/3}
.media-frame--1x1{aspect-ratio:1/1}
.media-caption{
  margin-top:10px;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.06em;
  color:var(--mist);
}

.reveal{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .5s ease,transform .5s ease;
}
.reveal.is-visible{opacity:1;transform:none}

/* ---------- 6. 分屏网格 ---------- */
.split{
  display:grid;
  gap:var(--gap);
  grid-template-columns:minmax(0,1fr);
  align-items:start;
}

/* ---------- 7. 页头框架 ---------- */
.skip-link{
  position:absolute;
  left:14px;
  top:-80px;
  z-index:200;
  padding:10px 18px;
  font-family:var(--font-mono);
  font-size:14px;
  letter-spacing:.06em;
  color:var(--anchor);
  background:var(--cyan);
  transition:top .16s ease;
}
.skip-link:focus{top:14px}

.site-header{
  position:sticky;
  top:0;
  z-index:90;
  background:var(--anchor);
  border-bottom:1px solid var(--hair-strong);
}

.scroll-progress{
  position:absolute;
  left:0;
  bottom:0;
  width:100%;
  height:2px;
  transform:scaleX(0);
  transform-origin:left center;
  background:linear-gradient(90deg,var(--cyan),var(--amber));
  z-index:6;
}

.frame-bar{
  position:relative;
  border-bottom:1px solid var(--hair);
  background:linear-gradient(180deg,rgba(19,28,46,.55),rgba(5,8,15,0));
}

.frame-inner{
  position:relative;
  display:flex;
  align-items:center;
  gap:clamp(12px,2vw,26px);
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--pad-inline);
  min-height:66px;
}

.frame-brand{
  display:flex;
  align-items:center;
  flex:0 0 auto;
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  padding:8px 0;
}
.brand-mark{
  position:relative;
  width:15px;
  height:15px;
  border:2px solid var(--cyan);
  transform:rotate(45deg);
  flex:0 0 auto;
}
.brand-mark::after{
  content:"";
  position:absolute;
  inset:3px;
  background:var(--cyan-dim);
}
.brand-text{display:flex;flex-direction:column;line-height:1.2}
.brand-name{
  font-family:var(--font-mono);
  font-size:1.02rem;
  font-weight:600;
  letter-spacing:.16em;
  color:var(--white);
}
.brand-domain{
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.05em;
  color:var(--mist);
}

.frame-nav{margin-left:auto}
.nav-list{
  display:flex;
  align-items:center;
  flex-wrap:wrap;
  gap:clamp(6px,1.4vw,20px);
}
.nav-link{
  position:relative;
  display:inline-block;
  padding:10px 2px;
  font-family:var(--font-mono);
  font-size:.93rem;
  letter-spacing:.08em;
  color:var(--mist);
  transition:color .18s ease;
}
.nav-link::after{
  content:"";
  position:absolute;
  left:0;right:0;bottom:5px;
  height:1px;
  background:var(--cyan);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .22s ease;
}
.nav-link:hover{color:var(--white)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--cyan)}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}

.nav-toggle{
  display:none;
  align-items:center;
  gap:10px;
  margin-left:auto;
  padding:9px 14px;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.12em;
  color:var(--cyan);
  border:1px solid var(--hair-cyan);
  cursor:pointer;
}
.nav-toggle-bars{
  position:relative;
  display:block;
  width:16px;
  height:2px;
  background:var(--cyan);
  transition:background-color .2s ease;
}
.nav-toggle-bars::before,
.nav-toggle-bars::after{
  content:"";
  position:absolute;
  left:0;
  width:16px;
  height:2px;
  background:var(--cyan);
  transition:transform .2s ease;
}
.nav-toggle-bars::before{top:-5px}
.nav-toggle-bars::after{top:5px}
.site-header[data-open] .nav-toggle-bars{background:transparent}
.site-header[data-open] .nav-toggle-bars::before{transform:translateY(5px) rotate(45deg)}
.site-header[data-open] .nav-toggle-bars::after{transform:translateY(-5px) rotate(-45deg)}

.tab-band{
  background:linear-gradient(90deg,var(--anchor) 0%,#0A101C 45%,var(--anchor) 100%);
  border-bottom:1px solid var(--hair);
}
.tab-inner{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--pad-inline);
  overflow-x:auto;
  overscroll-behavior-x:contain;
  scrollbar-width:none;
}
.tab-inner::-webkit-scrollbar{display:none}
.tab-list{
  display:flex;
  gap:2px;
  min-width:max-content;
}
.tab{
  position:relative;
  display:flex;
  align-items:center;
  gap:9px;
  padding:11px 15px;
  font-size:12.5px;
  letter-spacing:.1em;
  white-space:nowrap;
  color:var(--mist);
  border-top:2px solid transparent;
  transition:color .18s ease,background-color .18s ease,border-color .18s ease;
}
.tab-index{color:var(--cyan-dim);font-size:11.5px}
.tab:hover{color:var(--white);background:rgba(51,225,225,.06)}
.tab[aria-current="page"]{
  color:var(--cyan);
  border-top-color:var(--cyan);
  background:rgba(51,225,225,.08);
}
.tab[aria-current="page"] .tab-index{color:var(--cyan)}
.tab[aria-current="page"]::after{
  content:"";
  position:absolute;
  left:0;bottom:0;
  width:100%;height:1px;
  background:linear-gradient(90deg,transparent,var(--cyan) 50%,transparent);
  animation:tab-scan 3.4s ease-in-out infinite;
}
@keyframes tab-scan{
  0%{transform:translateX(-100%)}
  55%,100%{transform:translateX(100%)}
}

/* ---------- 8. 页脚 ---------- */
.site-footer{
  margin-top:clamp(48px,6vw,96px);
  background:var(--anchor);
  border-top:1px solid var(--hair-strong);
  color:var(--mist);
}
.footer-inner{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding:clamp(34px,4.5vw,64px) var(--pad-inline) 24px;
}
.footer-grid{
  display:grid;
  gap:clamp(26px,3.6vw,48px);
  grid-template-columns:minmax(0,1fr);
}
.footer-title{
  margin-bottom:14px;
  font-size:12.5px;
  letter-spacing:.2em;
  color:var(--cyan);
}
.footer-links li + li{margin-top:9px}
.footer-links a{
  position:relative;
  display:inline-block;
  font-size:14px;
  color:var(--mist);
  transition:color .18s ease;
}
.footer-links a::after{
  content:"";
  position:absolute;
  left:0;right:0;bottom:-2px;
  height:1px;
  background:var(--cyan);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .22s ease;
}
.footer-links a:hover{color:var(--cyan)}
.footer-links a:hover::after{transform:scaleX(1)}

.footer-contact{display:grid;gap:10px}
.footer-contact .copy-field{
  background:rgba(19,28,46,.7);
  border-color:var(--hair);
  border-left-color:var(--cyan-dim);
}
.contact-key{
  font-size:11.5px;
  letter-spacing:.14em;
  color:var(--mist);
}
.contact-val{
  font-size:13px;
  color:var(--white);
  overflow-wrap:anywhere;
}
.footer-note{
  margin-top:14px;
  font-size:13px;
  line-height:1.7;
  color:var(--mist);
}

.footer-stats{display:grid;gap:10px}
.stat{display:flex;align-items:baseline;gap:10px}
.stat-value{
  font-family:var(--font-mono);
  font-size:20px;
  letter-spacing:.04em;
  color:var(--cyan);
}
.stat-label{font-size:13px;color:var(--mist)}

.footer-end{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:8px 26px;
  margin-top:clamp(28px,4vw,52px);
  padding-top:20px;
  border-top:1px solid var(--hair);
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.06em;
  color:var(--mist);
}
.footer-sign{color:var(--white)}
.footer-legal{color:var(--mist)}
.footer-copy{color:var(--mist)}

/* ---------- 9. 响应式 ---------- */
@media (min-width:640px){
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (min-width:900px){
  .split{grid-template-columns:minmax(0,32fr) minmax(0,68fr)}
  .split--reverse{grid-template-columns:minmax(0,62fr) minmax(0,38fr)}
  .frame-brand{
    padding-right:clamp(12px,1.6vw,26px);
    border-right:1px solid var(--hair);
  }
  .footer-grid{grid-template-columns:repeat(4,minmax(0,1fr))}
}
@media (max-width:899px){
  html{scroll-padding-top:110px}
  .nav-toggle{display:inline-flex}
  .frame-nav{
    display:none;
    position:absolute;
    left:0;
    right:0;
    top:100%;
    z-index:20;
    padding:8px var(--pad-inline) 16px;
    background:var(--anchor);
    border-bottom:1px solid var(--hair-strong);
    box-shadow:0 24px 40px -30px rgba(0,0,0,.95);
  }
  .site-header[data-open] .frame-nav{display:block}
  .nav-list{
    flex-direction:column;
    align-items:stretch;
    gap:0;
  }
  .nav-link{
    display:block;
    padding:12px 2px;
    border-bottom:1px solid var(--hair);
    font-size:.98rem;
  }
  .nav-link::after{display:none}
  .nav-link[aria-current="page"]{
    padding-left:10px;
    border-left:2px solid var(--cyan);
    background:rgba(51,225,225,.07);
  }
}
@media (max-width:560px){
  .brand-domain{display:none}
  .tab{padding:10px 12px;font-size:12px}
  .footer-end{flex-direction:column;align-items:flex-start}
}

/* ---------- 10. 动效降级 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .reveal{opacity:1;transform:none}
  .btn:hover,.panel:hover{transform:none}
  .tab[aria-current="page"]::after{animation:none;opacity:0}
}