/* ===========================================================
   赢国平台 · 共享样式表 /assets/site.css
   墨蓝底 + 熔金铜强调 + 信号青/警示橙编码 · 直角 · 细线 · 精密网格
   =========================================================== */

/* ---------- 1. Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,h6,p,ul,ol,dl,dd,figure,blockquote{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}
hr{border:0;border-top:1px solid var(--ink-500);margin:0}

/* ---------- 2. Tokens ---------- */
:root{
  --ink-900:#0B1B2B;
  --ink-700:#14293D;
  --ink-500:#24405A;
  --copper-500:#C8952F;
  --copper-300:#E3C27A;
  --cyan-400:#2FC7C4;
  --cyan-600:#1B8F92;
  --amber-500:#E2703A;
  --paper-050:#F2F5F7;
  --graphite-600:#4A5A68;
  --stone-400:#9AAAB6;

  --shell-w:1280px;
  --gutter:clamp(18px,4.4vw,56px);
  --strip-h:34px;
  --bar-h:72px;
  --header-offset:calc(var(--strip-h) + var(--bar-h));

  --dur:200ms;
  --dur-fast:160ms;
  --ease:cubic-bezier(.22,.61,.36,1);

  --font-sans:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Arial,sans-serif;
  --font-serif:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",Georgia,"Times New Roman",serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;
}

/* ---------- 3. Base ---------- */
body{
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.75;
  color:var(--paper-050);
  background-color:var(--ink-900);
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
body.page-offset{padding-top:var(--header-offset)}
::selection{background:var(--copper-500);color:var(--ink-900)}

h1,h2,h3,h4{font-weight:800;letter-spacing:-.02em;line-height:1.14;color:inherit}
p{text-wrap:pretty}
strong{font-weight:700;color:var(--copper-300)}

a{transition:color var(--dur) var(--ease),background-color var(--dur) var(--ease),border-color var(--dur) var(--ease)}
:focus-visible{outline:2px solid var(--cyan-400);outline-offset:2px}
.section--paper :focus-visible,.on-light :focus-visible{outline-color:var(--cyan-600)}

.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.02em}
.display{font-size:clamp(38px,6vw,64px);font-weight:900;letter-spacing:-.03em;line-height:1.04}
.h2{font-size:clamp(26px,3.4vw,44px)}
.h3{font-size:clamp(20px,2.2vw,32px)}
.serif-title{font-family:var(--font-serif);font-weight:500;letter-spacing:0}
.lede{font-size:clamp(17px,1.6vw,21px);line-height:1.8;color:var(--stone-400)}
.eyebrow{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.18em;
  text-transform:uppercase;color:var(--copper-300);
}
.eyebrow::before{content:"";width:22px;height:1px;background:var(--copper-500)}
.prose{font-size:17px;line-height:1.9;color:var(--graphite-600)}
.prose p + p{margin-top:1.1em}
.section--paper .prose{color:var(--graphite-600)}

.rule{height:1px;background:var(--ink-500);border:0}
.hairline{border-top:1px solid var(--ink-500)}

/* ---------- 4. Layout ---------- */
.shell{
  width:100%;
  max-width:var(--shell-w);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.section{position:relative;padding:clamp(56px,7.5vw,110px) 0}
.section--deep{background-color:var(--ink-700)}
.section--paper{background-color:var(--paper-050);color:var(--ink-900)}
.grid{display:grid;gap:clamp(20px,2.6vw,36px)}
.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-9{grid-column:span 9}
.col-12{grid-column:span 12}

/* ---------- 5. Buttons & tags ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.55em;
  padding:.82em 1.5em;
  font-size:15px;letter-spacing:.04em;line-height:1.2;
  border:1px solid var(--copper-500);
  color:var(--paper-050);
  background:transparent;
  transition:background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.btn:hover{background-color:var(--copper-500);color:var(--ink-900)}
.btn--sm{padding:.6em 1.05em;font-size:13px;letter-spacing:.06em}
.btn--solid{background-color:var(--copper-500);color:var(--ink-900)}
.btn--solid:hover{background-color:var(--copper-300);border-color:var(--copper-300);color:var(--ink-900)}
.btn--ghost{border-color:var(--ink-500);color:var(--stone-400)}
.btn--ghost:hover{background-color:rgba(47,199,196,.10);border-color:var(--cyan-400);color:var(--cyan-400)}
.btn--signal{border-color:rgba(47,199,196,.6);color:var(--cyan-400)}
.btn--signal:hover{background-color:var(--cyan-400);border-color:var(--cyan-400);color:var(--ink-900)}
.section--paper .btn--ghost{border-color:#C7D2DA;color:var(--graphite-600)}
.section--paper .btn--ghost:hover{background-color:rgba(27,143,146,.10);border-color:var(--cyan-600);color:var(--cyan-600)}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:3px 9px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;line-height:1.6;
  border:1px solid var(--ink-500);color:var(--stone-400);
}
.tag--copper{border-color:rgba(200,149,47,.55);color:var(--copper-300)}
.tag--signal{border-color:rgba(47,199,196,.5);color:var(--cyan-400)}
.tag--amber{border-color:rgba(226,112,58,.5);color:var(--amber-500)}

/* ---------- 6. Breadcrumb ---------- */
.breadcrumb{padding:22px 0 0}
.breadcrumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:10px;font-size:13px;color:var(--stone-400)}
.breadcrumb__item{display:inline-flex;align-items:center;gap:10px}
.breadcrumb__item + .breadcrumb__item::before{content:"/";color:var(--ink-500)}
.breadcrumb__item a:hover{color:var(--copper-300)}
.breadcrumb__item [aria-current="page"]{color:var(--copper-300)}
.section--paper .breadcrumb__list{color:var(--graphite-600)}

/* ---------- 7. Media frames ---------- */
.media-frame{
  position:relative;overflow:hidden;
  background-color:var(--ink-700);
  border:1px solid var(--ink-500);
}
.media-frame img{width:100%;height:100%;object-fit:cover}
.media-frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:
    linear-gradient(rgba(36,64,90,.45) 1px,transparent 1px),
    linear-gradient(90deg,rgba(36,64,90,.45) 1px,transparent 1px);
  background-size:36px 36px;
  mix-blend-mode:screen;opacity:.5;
}
.media-frame--16x9{aspect-ratio:16/9}
.media-frame--4x3{aspect-ratio:4/3}
.media-frame--1x1{aspect-ratio:1/1}
.media-frame--tall{aspect-ratio:3/4}
.media-frame--place{display:grid;place-items:center;color:var(--stone-400);font-family:var(--font-mono);font-size:12px;letter-spacing:.14em}
.media-frame__caption{margin-top:10px;font-size:12px;letter-spacing:.06em;color:var(--stone-400)}
.section--paper .media-frame{border-color:#D5DEE4;background-color:#E5EBEF}
.section--paper .media-frame__caption{color:var(--graphite-600)}

/* ---------- 8. Skip link ---------- */
.skip-link{
  position:fixed;top:-100px;left:var(--gutter);z-index:200;
  padding:10px 18px;
  background-color:var(--copper-500);color:var(--ink-900);
  font-size:14px;letter-spacing:.06em;
  transition:top var(--dur-fast) var(--ease);
}
.skip-link:focus{top:8px}

/* ---------- 9. Header ---------- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:90;
  background-color:transparent;
  transition:background-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.site-header::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:linear-gradient(180deg,rgba(11,27,43,.94) 0%,rgba(11,27,43,.58) 58%,rgba(11,27,43,0) 100%);
  transition:opacity var(--dur) var(--ease);
}
.site-header[data-scrolled]{
  background-color:var(--ink-900);
  box-shadow:0 1px 0 var(--ink-500),0 22px 44px -34px rgba(0,0,0,.95);
}
.site-header[data-scrolled]::before{opacity:0}

.scroll-progress{
  position:absolute;left:0;bottom:0;z-index:2;
  width:100%;height:2px;transform:scaleX(0);transform-origin:0 50%;
  background:linear-gradient(90deg,var(--cyan-400),var(--copper-500));
  pointer-events:none;
}

.header-strip{
  position:relative;height:var(--strip-h);
  border-bottom:1px solid rgba(36,64,90,.55);
  font-size:12px;color:var(--stone-400);
}
.header-strip__inner{display:flex;align-items:center;justify-content:space-between;gap:16px;height:100%}
.strip-batch{display:inline-flex;align-items:center;gap:9px;letter-spacing:.05em;white-space:nowrap}
.strip-batch__dot{
  width:6px;height:6px;flex:none;background-color:var(--copper-500);
  box-shadow:0 0 0 3px rgba(200,149,47,.16);
}
.strip-batch__date{color:var(--copper-300);font-size:12px}
.strip-links{display:flex;align-items:center;gap:20px;white-space:nowrap}
.strip-links a{
  padding-bottom:2px;border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.strip-links a:hover{color:var(--copper-300);border-bottom-color:var(--copper-500)}

.header-bar{position:relative;height:var(--bar-h);transition:height var(--dur) var(--ease)}
.header-bar__inner{display:flex;align-items:center;justify-content:space-between;gap:22px;height:100%}

.brand{display:inline-flex;align-items:center;gap:12px;flex:none}
.brand__mark{
  width:26px;height:26px;flex:none;
  border:1px solid var(--ink-500);
  background-image:
    linear-gradient(var(--copper-500),var(--copper-500)),
    linear-gradient(var(--cyan-400),var(--cyan-400));
  background-size:38% 38%;
  background-position:3px 3px,calc(100% - 3px) calc(100% - 3px);
  background-repeat:no-repeat;
  transition:border-color var(--dur) var(--ease),background-color var(--dur) var(--ease);
}
.brand:hover .brand__mark{border-color:var(--copper-500)}
.brand__text{display:flex;flex-direction:column;line-height:1.05}
.brand__name{font-size:19px;font-weight:800;letter-spacing:.02em;color:var(--paper-050)}
.brand__en{font-size:10px;letter-spacing:.24em;color:var(--stone-400);margin-top:3px}

.site-nav__list{display:flex;align-items:center;gap:clamp(10px,1.9vw,28px)}
.site-nav__list > li{position:relative}
.site-nav__link{
  position:relative;display:inline-block;
  padding:9px 2px;
  font-size:15px;letter-spacing:.06em;color:var(--paper-050);
  transition:color var(--dur) var(--ease);
}
.site-nav__link::before{
  content:attr(data-idx);
  font-family:var(--font-mono);font-size:10px;letter-spacing:.08em;
  vertical-align:super;margin-right:5px;color:var(--stone-400);
  transition:color var(--dur) var(--ease);
}
.site-nav__link::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:1px;
  background-color:var(--copper-500);
  transform:scaleX(0);transform-origin:0 50%;
  transition:transform var(--dur) var(--ease);
}
.site-nav__link:hover{color:var(--copper-300)}
.site-nav__link:hover::before{color:var(--copper-300)}
.site-nav__link:hover::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:var(--copper-300)}
.site-nav__link[aria-current="page"]::before{color:var(--copper-500)}
.site-nav__link[aria-current="page"]::after{transform:scaleX(1);background-color:var(--copper-300)}

.header-actions{display:flex;align-items:center;gap:12px;flex:none}

.nav-toggle{
  display:none;align-items:center;gap:9px;
  padding:9px 11px;
  border:1px solid var(--ink-500);
  color:var(--paper-050);
  font-size:12px;letter-spacing:.14em;
  transition:border-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan-400);color:var(--cyan-400)}
.nav-toggle__bars{position:relative;display:block;width:18px;height:12px;flex:none}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";position:absolute;left:0;right:0;height:1px;background-color:currentColor;
  transition:transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.nav-toggle__bars::before{top:1px;box-shadow:0 5px 0 currentColor}
.nav-toggle__bars::after{top:11px}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{transform:translateY(5px) rotate(45deg);box-shadow:none}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{transform:translateY(-5px) rotate(-45deg)}
.nav-toggle__label{line-height:1}

/* ---------- 10. Footer ---------- */
.site-footer{
  position:relative;
  background-color:var(--ink-900);
  border-top:1px solid var(--ink-500);
  color:var(--stone-400);
  font-size:14px;
  overflow:hidden;
}
.site-footer::before{
  content:"";position:absolute;inset:0;pointer-events:none;opacity:.4;
  background-image:
    linear-gradient(rgba(36,64,90,.55) 1px,transparent 1px),
    linear-gradient(90deg,rgba(36,64,90,.55) 1px,transparent 1px);
  background-size:44px 44px;
}
.footer-grid{
  position:relative;z-index:1;
  display:grid;
  grid-template-columns:repeat(6,minmax(0,1fr));
  gap:44px 30px;
  padding:clamp(48px,6vw,78px) 0 46px;
}
.footer-col{min-width:0}
.footer-col--brand{grid-column:span 2}
.footer-col--contact{grid-column:span 2}

.brand--footer{margin-bottom:16px}
.footer-brand__desc{max-width:32ch;line-height:1.8;color:var(--stone-400)}
.footer-brand__meta{
  margin-top:14px;font-size:12px;letter-spacing:.06em;line-height:1.9;
  color:var(--copper-300);
}

.footer-title{
  display:flex;align-items:center;gap:12px;
  margin-bottom:18px;
  font-family:var(--font-mono);font-size:11px;font-weight:400;
  letter-spacing:.2em;text-transform:uppercase;color:var(--copper-300);
}
.footer-title::after{content:"";flex:1;height:1px;background-color:var(--ink-500)}

.footer-list{display:flex;flex-direction:column;gap:11px}
.footer-list a{position:relative;display:inline-block;color:var(--stone-400);transition:color var(--dur) var(--ease)}
.footer-list a::before{
  content:"";position:absolute;left:-14px;top:50%;height:1px;width:0;
  background-color:var(--copper-500);
  transition:width var(--dur) var(--ease);
}
.footer-list a:hover{color:var(--paper-050)}
.footer-list a:hover::before{width:8px}

.footer-contact{display:flex;flex-direction:column;gap:14px}
.footer-contact__row{display:flex;flex-direction:column;gap:3px}
.footer-contact__label{font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;color:var(--stone-400)}
.footer-contact__value{color:var(--paper-050);font-size:15px;line-height:1.6;word-break:break-word}
.footer-note{margin:18px 0 20px;font-size:13px;line-height:1.8;color:var(--stone-400);max-width:44ch}

.footer-base{
  position:relative;z-index:1;
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:16px;
  padding:22px 0 34px;
  border-top:1px solid var(--ink-500);
  font-size:13px;
}
.footer-base__copy{color:var(--stone-400)}
.footer-legal{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;
  color:var(--stone-400);
}
.to-top{
  padding:8px 14px;
  border:1px solid var(--ink-500);
  color:var(--stone-400);
  font-size:12px;letter-spacing:.14em;
  transition:border-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.to-top:hover{border-color:var(--copper-500);color:var(--copper-300)}

/* ---------- 11. Responsive ---------- */
@media (min-width:961px){
  .site-header[data-scrolled] .header-bar{height:58px}
}
@media (max-width:1080px){
  .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,.col-9{grid-column:span 6}
  .footer-grid{grid-template-columns:repeat(4,minmax(0,1fr))}
  .footer-col--brand,.footer-col--contact{grid-column:span 2}
}
@media (max-width:960px){
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:fixed;top:var(--header-offset);left:0;right:0;
    max-height:calc(100vh - var(--header-offset));
    overflow-y:auto;
    padding:10px var(--gutter) 24px;
    background-color:var(--ink-700);
    border-top:1px solid var(--ink-500);
    border-bottom:1px solid var(--ink-500);
    opacity:0;visibility:hidden;pointer-events:none;
    transform:translateY(-8px);
    transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease),visibility var(--dur) var(--ease);
  }
  .site-nav[data-open]{
    opacity:1;visibility:visible;pointer-events:auto;transform:translateY(0);
  }
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0}
  .site-nav__list > li + li{border-top:1px solid rgba(36,64,90,.7)}
  .site-nav__link{display:block;padding:15px 0;font-size:16px}
  .site-nav__link::after{display:none}
  .site-nav__link[aria-current="page"]{color:var(--copper-300)}
  .site-nav__link[aria-current="page"]::before{color:var(--copper-500)}
}
@media (max-width:760px){
  .header-cta{display:none}
  .strip-links a:not(:last-child){display:none}
}
@media (max-width:680px){
  .grid--12{grid-template-columns:minmax(0,1fr)}
  .col-3,.col-4,.col-5,.col-6,.col-7,.col-8,.col-9,.col-12{grid-column:span 1}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:34px;padding-top:44px}
  .footer-col--brand,.footer-col--contact{grid-column:auto}
  .footer-base{flex-direction:column;align-items:flex-start;gap:12px}
  .footer-note{max-width:none}
}
@media (max-width:420px){
  .header-strip{font-size:11px}
  .brand__en{display:none}
}

/* ---------- 12. Motion preferences ---------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.01ms !important;
    animation-iteration-count:1 !important;
    transition-property:color,background-color,border-color,opacity !important;
    transition-duration:120ms !important;
  }
  .scroll-progress{transition:none}
}