/* ============================================================
   BG电子注册 · 共享样式表 /assets/site.css
   深空黑信号板 · Bento 展签体系
   ============================================================ */

:root{
  --ink-void:#05070C;
  --ink-slate:#0F1622;
  --line-steel:#2B3646;
  --blue-volt:#2F6BFF;
  --cyan-signal:#24E0D6;
  --magenta-neon:#FF4FD8;
  --white-hi:#F3F7FF;
  --grey-index:#93A3B8;
  --mist:#E9EEF7;
  --ink-deep:#0B1220;
  --amber:#FFC46B;

  --font-display:"Inter Tight","Source Han Sans SC","Noto Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-body:"Inter","Source Han Sans SC","Noto Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,monospace;

  --shell:1280px;
  --gutter:48px;
  --gap:24px;
  --r-capsule:999px;
  --r-card:16px;

  --ease:cubic-bezier(.22,.61,.36,1);
  color-scheme:dark;
}

/* ---------- reset ---------- */
*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd,address{margin:0;}
ul,ol{list-style:none;padding:0;}
a{color:inherit;text-decoration:none;}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer;}
img,svg,video{display:block;max-width:100%;}
address{font-style:normal;}
[hidden]{display:none !important;}
table{border-collapse:collapse;width:100%;}

:focus-visible{outline:2px solid var(--cyan-signal);outline-offset:2px;}
::selection{background:rgba(36,224,214,.28);color:var(--white-hi);}

/* ---------- base ---------- */
body{
  background:var(--ink-void);
  color:var(--white-hi);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  min-height:100vh;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:0;
  pointer-events:none;
  background:
    radial-gradient(660px 440px at 84% -8%, rgba(47,107,255,.20), transparent 70%),
    radial-gradient(540px 400px at -10% 24%, rgba(36,224,214,.10), transparent 72%),
    radial-gradient(420px 320px at 62% 108%, rgba(255,79,216,.08), transparent 74%);
}
main{display:block;position:relative;z-index:1;}

/* ---------- skip link ---------- */
.skip-link{
  position:fixed;
  top:12px;
  left:12px;
  z-index:200;
  transform:translateY(-180%);
  padding:10px 18px;
  border-radius:var(--r-capsule);
  background:var(--cyan-signal);
  color:#04121A;
  font-size:13px;
  font-weight:700;
  letter-spacing:.02em;
  transition:transform .2s var(--ease);
}
.skip-link:focus{transform:translateY(0);}

/* ============================================================
   悬浮胶囊导航
   ============================================================ */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  padding:18px 0 8px;
  transition:padding .28s var(--ease);
}
.site-header::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:140px;
  pointer-events:none;
  background:linear-gradient(180deg,rgba(5,7,12,.96) 34%,rgba(5,7,12,0));
}

.header-capsule{
  position:relative;
  width:min(var(--shell), calc(100% - var(--gutter)));
  margin:0 auto;
  display:flex;
  align-items:center;
  gap:14px;
  padding:9px 10px 9px 12px;
  background:rgba(15,22,34,.88);
  border:1px solid var(--line-steel);
  border-radius:var(--r-capsule);
  box-shadow:0 26px 60px -42px rgba(0,0,0,.96), inset 0 1px 0 rgba(243,247,255,.04);
  transition:padding .28s var(--ease), width .28s var(--ease), background .28s var(--ease), border-color .28s var(--ease);
}
.header-capsule::after{
  content:"";
  position:absolute;
  left:11%;
  right:11%;
  bottom:-1px;
  height:1px;
  background:linear-gradient(90deg,transparent,var(--blue-volt) 18%,var(--cyan-signal) 52%,var(--magenta-neon) 82%,transparent);
  opacity:0;
  transition:opacity .3s var(--ease);
  pointer-events:none;
}
[data-header][data-condensed] .header-capsule{
  width:min(1120px, calc(100% - var(--gutter)));
  padding:5px 8px 5px 10px;
  background:rgba(11,18,32,.95);
  border-color:#33405340;
}
[data-header][data-condensed] .header-capsule::after{opacity:.9;}
[data-header][data-condensed] .site-header{padding-top:12px;}

/* ---------- 品牌 ---------- */
.brand{
  display:flex;
  align-items:center;
  gap:10px;
  flex:0 0 auto;
  padding:3px 10px 3px 3px;
  border-radius:var(--r-capsule);
}
.brand-sigil{
  position:relative;
  flex:0 0 auto;
  width:32px;
  height:32px;
  border-radius:11px;
  border:1px solid var(--line-steel);
  background:linear-gradient(150deg,#152340 0%,#070B14 100%);
  overflow:hidden;
}
.brand-sigil::before{
  content:"";
  position:absolute;
  left:5px;
  right:5px;
  top:50%;
  height:1px;
  transform:translateY(-50%) rotate(-24deg);
  background:linear-gradient(90deg,var(--cyan-signal),var(--blue-volt));
  box-shadow:0 0 10px rgba(36,224,214,.75);
}
.brand-sigil::after{
  content:"";
  position:absolute;
  top:5px;
  right:5px;
  width:5px;
  height:5px;
  border-radius:50%;
  background:var(--magenta-neon);
  box-shadow:0 0 8px rgba(255,79,216,.8);
}
.brand-words{display:flex;flex-direction:column;line-height:1.12;}
.brand-name{
  font-family:var(--font-display);
  font-size:15px;
  font-weight:800;
  letter-spacing:.01em;
  color:var(--white-hi);
  white-space:nowrap;
}
.brand-sub{
  font-family:var(--font-mono);
  font-size:9px;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--grey-index);
  white-space:nowrap;
}

/* ---------- 上级栏目标记 ---------- */
.nav-sector{
  flex:0 0 auto;
  padding-left:12px;
  border-left:1px solid var(--line-steel);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--cyan-signal);
  white-space:nowrap;
}

/* ---------- 导航主体 ---------- */
.nav{
  display:flex;
  flex:1 1 auto;
  min-width:0;
  align-items:center;
  justify-content:flex-end;
  gap:16px;
}
.nav-list{
  display:flex;
  align-items:center;
  gap:4px;
}
.nav-item{display:block;min-width:0;}
.nav-link{
  position:relative;
  display:inline-block;
  padding:8px 13px;
  border-radius:var(--r-capsule);
  border:1px solid transparent;
  font-size:14px;
  line-height:1.2;
  color:var(--grey-index);
  white-space:nowrap;
  transition:color .2s var(--ease), border-color .2s var(--ease), background .2s var(--ease), transform .2s var(--ease);
}
.nav-link:hover{
  color:var(--white-hi);
  border-color:var(--line-steel);
  background:rgba(47,107,255,.10);
  transform:translateY(-1px);
}
.nav-link[aria-current="page"]{
  color:var(--white-hi);
  border-color:rgba(36,224,214,.36);
  background:rgba(36,224,214,.08);
}
.nav-link[aria-current="page"]::after{
  content:"";
  position:absolute;
  left:-1px;
  top:50%;
  width:4px;
  height:4px;
  border-radius:50%;
  transform:translate(-50%,-50%);
  background:var(--cyan-signal);
  box-shadow:0 0 10px var(--cyan-signal);
}

.nav-tail{
  display:flex;
  align-items:center;
  gap:8px;
  padding-left:12px;
  border-left:1px solid var(--line-steel);
}
.ver-chip{
  display:inline-flex;
  align-items:center;
  padding:3px 8px;
  border-radius:6px;
  border:1px solid rgba(36,224,214,.38);
  background:rgba(36,224,214,.08);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  color:var(--cyan-signal);
}

/* ---------- 移动按钮 ---------- */
.nav-toggle{
  display:none;
  margin-left:auto;
  align-items:center;
  gap:8px;
  padding:8px 13px;
  border-radius:var(--r-capsule);
  border:1px solid var(--line-steel);
  color:var(--white-hi);
  background:rgba(243,247,255,.03);
  transition:border-color .2s var(--ease), color .2s var(--ease);
}
.nav-toggle-glyph{display:flex;flex-direction:column;gap:3px;width:16px;}
.nav-toggle-glyph i{
  display:block;
  height:1.5px;
  border-radius:2px;
  background:currentColor;
  transition:transform .22s var(--ease), opacity .18s var(--ease);
}
.nav-toggle-label{font-size:13px;font-weight:700;letter-spacing:.02em;}
.nav-toggle[aria-expanded="true"]{
  border-color:rgba(36,224,214,.5);
  color:var(--cyan-signal);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-glyph i:nth-child(1){transform:translateY(4.5px) rotate(45deg);}
.nav-toggle[aria-expanded="true"] .nav-toggle-glyph i:nth-child(2){opacity:0;}
.nav-toggle[aria-expanded="true"] .nav-toggle-glyph i:nth-child(3){transform:translateY(-4.5px) rotate(-45deg);}

/* ============================================================
   通用按钮
   ============================================================ */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:11px 18px;
  border-radius:var(--r-capsule);
  border:1px solid transparent;
  font-family:var(--font-body);
  font-size:14px;
  font-weight:700;
  line-height:1;
  white-space:nowrap;
  transition:transform .18s var(--ease), background .18s var(--ease), border-color .18s var(--ease), color .18s var(--ease), box-shadow .18s var(--ease);
}
.btn-sm{padding:8px 14px;font-size:13px;}
.btn-solid{
  background:linear-gradient(120deg,var(--blue-volt) 0%,#4E8BFF 100%);
  color:#FFFFFF;
  box-shadow:0 14px 30px -18px rgba(47,107,255,.95);
}
.btn-solid:hover{
  transform:translateY(-2px);
  box-shadow:0 20px 38px -18px rgba(47,107,255,1);
}
.btn-ghost{
  border-color:var(--line-steel);
  background:rgba(243,247,255,.02);
  color:var(--white-hi);
}
.btn-ghost:hover{
  transform:translateY(-2px);
  border-color:rgba(36,224,214,.5);
  color:var(--cyan-signal);
}

/* ============================================================
   版心 / 分区 / 排版
   ============================================================ */
.shell{
  width:min(var(--shell), calc(100% - var(--gutter)));
  margin-inline:auto;
}
.page-band{padding:72px 0;}
.page-band + .page-band{padding-top:0;}

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:9px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--cyan-signal);
}
.eyebrow::before{content:"";width:18px;height:1px;background:currentColor;}

.display-title{
  font-family:var(--font-display);
  font-weight:280;
  font-size:clamp(44px,7.4vw,104px);
  line-height:.98;
  letter-spacing:-.03em;
  color:var(--white-hi);
}
.section-title{
  font-family:var(--font-display);
  font-size:clamp(26px,3.2vw,38px);
  font-weight:800;
  line-height:1.16;
  letter-spacing:-.01em;
  color:var(--white-hi);
}
.plate-title{
  font-family:var(--font-display);
  font-size:20px;
  font-weight:700;
  line-height:1.3;
  color:var(--white-hi);
}
.lede{
  max-width:62ch;
  font-size:16px;
  line-height:1.8;
  color:var(--grey-index);
}
.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  justify-content:space-between;
  gap:16px 32px;
  margin-bottom:40px;
}
.section-head > *{min-width:0;}

.index-num{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.16em;
  color:var(--grey-index);
}

/* ---------- 浅雾底阅读分区 ---------- */
.band-mist{
  background:var(--mist);
  color:var(--ink-deep);
  border-top:1px solid rgba(11,18,32,.08);
  border-bottom:1px solid rgba(11,18,32,.08);
}
.band-mist h1,
.band-mist h2,
.band-mist h3,
.band-mist .section-title,
.band-mist .display-title,
.band-mist .plate-title{color:var(--ink-deep);}
.band-mist p,
.band-mist li,
.band-mist .lede{color:#33405A;}
.band-mist .eyebrow{color:#1B54D8;}
.band-mist .index-num,
.band-mist .plate-label{color:#5A6A85;}
.band-mist .plate{
  background:#FFFFFF;
  border-color:rgba(11,18,32,.10);
  box-shadow:0 20px 44px -36px rgba(11,18,32,.55), inset 0 1px 0 #FFFFFF;
}
.band-mist .tag{color:#3A4A66;border-color:rgba(11,18,32,.16);}

/* ---------- 面包屑 ---------- */
.crumbs{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--grey-index);
}
.crumbs ol{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
}
.crumbs li{display:flex;align-items:center;gap:10px;}
.crumbs li + li::before{content:"/";color:#3B4759;}
.crumbs a{color:var(--grey-index);transition:color .18s var(--ease);}
.crumbs a:hover{color:var(--cyan-signal);}
.crumbs [aria-current="page"]{color:var(--white-hi);}

/* ============================================================
   网格骨架
   ============================================================ */
.grid{display:grid;gap:var(--gap);}
.grid-12{grid-template-columns:repeat(12,minmax(0,1fr));}
.col-3{grid-column:span 3;}
.col-4{grid-column:span 4;}
.col-5{grid-column:span 5;}
.col-6{grid-column:span 6;}
.col-7{grid-column:span 7;}
.col-8{grid-column:span 8;}
.col-12{grid-column:span 12;}

/* ---------- 展签卡片 ---------- */
.plate{
  position:relative;
  padding:22px;
  border:1px solid var(--line-steel);
  border-radius:var(--r-card);
  background:linear-gradient(160deg,rgba(15,22,34,.92) 0%,rgba(9,13,20,.92) 100%);
  box-shadow:inset 0 1px 0 rgba(243,247,255,.035), 0 24px 54px -46px rgba(0,0,0,.95);
  transition:transform .2s var(--ease), border-color .2s var(--ease);
}
.plate:hover{border-color:rgba(47,107,255,.42);}
.plate-label{
  display:block;
  margin-bottom:10px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--grey-index);
}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border-radius:var(--r-capsule);
  border:1px solid var(--line-steel);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--grey-index);
}
.tag-signal{
  color:var(--cyan-signal);
  border-color:rgba(36,224,214,.36);
  background:rgba(36,224,214,.07);
}

/* ---------- 图片容器基础规则 ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  aspect-ratio:16 / 10;
  border:1px solid var(--line-steel);
  border-radius:var(--r-card);
  background:
    radial-gradient(120% 120% at 12% 6%, rgba(47,107,255,.26), transparent 58%),
    radial-gradient(90% 90% at 88% 94%, rgba(36,224,214,.16), transparent 62%),
    linear-gradient(150deg,#0B1220 0%,#070B12 100%);
}
.media-frame > img{
  width:100%;
  height:100%;
  object-fit:cover;
  transition:transform .4s var(--ease);
}
.media-frame > img[alt]:not([alt=""]){color:var(--grey-index);font-size:12px;}
.media-frame[data-ratio="21-9"]{aspect-ratio:21 / 9;}
.media-frame[data-ratio="16-9"]{aspect-ratio:16 / 9;}
.media-frame[data-ratio="16-10"]{aspect-ratio:16 / 10;}
.media-frame[data-ratio="4-3"]{aspect-ratio:4 / 3;}
.media-frame[data-ratio="1-1"]{aspect-ratio:1 / 1;}
.media-frame[data-ratio="3-4"]{aspect-ratio:3 / 4;}

/* ---------- 进场 ---------- */
.reveal{transition:opacity .5s var(--ease), transform .5s var(--ease);}
.js-motion .reveal{opacity:0;transform:translateY(18px);}
.js-motion .reveal.is-in{opacity:1;transform:none;}

/* ============================================================
   页脚 · 宽幅信号线
   ============================================================ */
.site-footer{
  position:relative;
  z-index:1;
  margin-top:120px;
  background:linear-gradient(180deg,#070B13 0%,#05070C 100%);
  border-top:1px solid var(--line-steel);
  color:var(--grey-index);
  font-size:14px;
}
.footer-signal{
  height:2px;
  background:linear-gradient(90deg,transparent 0%,rgba(47,107,255,.85) 14%,var(--cyan-signal) 46%,var(--magenta-neon) 78%,transparent 100%);
  opacity:.75;
}
.footer-inner{
  width:min(var(--shell), calc(100% - var(--gutter)));
  margin:0 auto;
  padding:68px 0 44px;
  display:grid;
  grid-template-columns:minmax(240px,1fr) 2.4fr;
  gap:56px;
  align-items:start;
}
.footer-brand{display:flex;flex-direction:column;gap:16px;}
.footer-brand .brand{padding:0;}
.footer-brand .brand-name{font-size:17px;}
.footer-brand .brand-sub{letter-spacing:.2em;}
.footer-note{
  max-width:34ch;
  font-size:13px;
  line-height:1.85;
  color:var(--grey-index);
}
.footer-cols{
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:28px;
}
.footer-col{display:flex;flex-direction:column;gap:14px;min-width:0;}
.footer-col-title{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--white-hi);
}
.footer-list{display:flex;flex-direction:column;gap:9px;}
.footer-list a{
  display:inline-block;
  font-size:13.5px;
  color:var(--grey-index);
  transition:color .18s var(--ease), transform .18s var(--ease);
}
.footer-list a:hover{color:var(--cyan-signal);transform:translateX(3px);}

.footer-contact{display:flex;flex-direction:column;gap:9px;}
.footer-contact-line{
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.02em;
  color:var(--white-hi);
  word-break:break-word;
}
.footer-contact-line--addr{
  font-family:var(--font-body);
  font-size:13px;
  letter-spacing:0;
  line-height:1.75;
  color:var(--grey-index);
}

.footer-base{
  width:min(var(--shell), calc(100% - var(--gutter)));
  margin:0 auto;
  padding:20px 0 36px;
  border-top:1px solid var(--line-steel);
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px 24px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--grey-index);
}
.footer-copy{color:var(--grey-index);}
.footer-icp{color:var(--cyan-signal);}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width:1180px){
  :root{--gutter:40px;}
  .nav-list{gap:0;}
  .nav-link{padding:8px 10px;font-size:13.5px;}
  .nav{gap:12px;}
}
@media (max-width:1060px){
  .nav-tail-ghost{display:none;}
  .brand-sub{display:none;}
}
@media (max-width:900px){
  :root{--gutter:32px;}
  .site-header{padding:12px 0 6px;}
  .header-capsule{padding:8px 8px 8px 10px;gap:10px;}
  .nav-sector{display:none;}
  .nav-toggle{display:inline-flex;}
  .nav{
    position:absolute;
    top:calc(100% + 10px);
    left:0;
    right:0;
    z-index:5;
    flex-direction:column;
    align-items:stretch;
    justify-content:flex-start;
    gap:10px;
    padding:12px;
    border:1px solid var(--line-steel);
    border-radius:22px;
    background:rgba(11,18,32,.98);
    box-shadow:0 34px 74px -46px rgba(0,0,0,1);
    opacity:0;
    visibility:hidden;
    transform:translateY(-6px);
    transition:opacity .2s var(--ease), transform .2s var(--ease), visibility .2s var(--ease);
  }
  .nav[data-open="true"]{opacity:1;visibility:visible;transform:none;}
  .nav-list{flex-direction:column;align-items:stretch;gap:2px;}
  .nav-item{flex:1 1 auto;}
  .nav-link{display:block;padding:12px 16px;border-radius:14px;font-size:15px;}
  .nav-link:hover{transform:none;}
  .nav-link[aria-current="page"]::after{left:auto;right:16px;top:50%;transform:translate(0,-50%);}
  .nav-tail{
    flex-direction:column;
    align-items:stretch;
    gap:8px;
    padding:12px 0 0;
    border-left:0;
    border-top:1px solid var(--line-steel);
  }
  .nav-tail .btn{width:100%;}
  .nav-tail-ghost{display:inline-flex;}
  .ver-chip{align-self:flex-start;}

  .grid-12{grid-template-columns:repeat(6,minmax(0,1fr));}
  .col-3,.col-4,.col-5{grid-column:span 3;}
  .col-6,.col-7,.col-8{grid-column:span 6;}

  .footer-inner{grid-template-columns:1fr;gap:44px;padding:56px 0 36px;}
  .footer-cols{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px 24px;}
  .site-footer{margin-top:96px;}
  .page-band{padding:56px 0;}
}
@media (max-width:620px){
  :root{--gutter:32px;--gap:16px;}
  body{font-size:15.5px;}
  .header-capsule{width:calc(100% - 32px);}
  [data-header][data-condensed] .header-capsule{width:calc(100% - 32px);}
  .shell,
  .footer-inner,
  .footer-base{width:calc(100% - 32px);}
  .grid-12{grid-template-columns:1fr;}
  .col-3,.col-4,.col-5,.col-6,.col-7,.col-8,.col-12{grid-column:span 1;}
  .footer-cols{grid-template-columns:1fr;}
  .display-title{font-size:clamp(38px,12vw,64px);}
  .page-band{padding:44px 0;}
  .footer-base{letter-spacing:.1em;}
}

/* ---------- 动效与可访问性 ---------- */
@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-motion .reveal{opacity:1 !important;transform:none !important;}
  .skip-link{transition:none;}
}