/* ==========================================================================
   欧博官网 (oubo-ai.com.cn) — 全站样式
   Design language: Executive business-operations workbench + editorial report
   ========================================================================== */

:root{
  --bg:#f6f4ef;
  --bg-soft:#efece3;
  --surface:#ffffff;
  --surface-alt:#f9f7f2;
  --line:#e2ddd0;
  --line-strong:#cfc8b6;
  --text:#20242a;
  --text-soft:#4c525b;
  --text-mute:#767c85;
  --primary:#124c49;
  --primary-dark:#0b3634;
  --primary-soft:#e4ece9;
  --growth:#2f7a52;
  --growth-soft:#e5f0e7;
  --forecast:#5457a6;
  --forecast-soft:#eaeafa;
  --alert:#c07a2e;
  --alert-soft:#f8ecd9;
  --risk:#b2543f;
  --risk-soft:#f7e6e0;
  --radius-sm:6px;
  --radius:10px;
  --radius-lg:18px;
  --shadow:0 1px 2px rgba(24,26,20,.04), 0 8px 24px -12px rgba(24,26,20,.12);
  --shadow-sm:0 1px 3px rgba(24,26,20,.08);
  --font:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  --max:1200px;
  --read:800px;
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--font);
  background:var(--bg);
  color:var(--text);
  line-height:1.75;
  font-size:16px;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
svg{display:block;max-width:100%;height:auto}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}
ul,ol{margin:0;padding:0}
li{list-style:none}
h1,h2,h3,h4,p,figure{margin:0}
button{font-family:inherit;cursor:pointer}
.container{max-width:var(--max);margin:0 auto;padding:0 24px}
.read{max-width:var(--read);margin-left:auto;margin-right:auto}
.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap}
.skip-link{position:absolute;left:-999px;top:0;background:var(--primary);color:#fff;padding:10px 16px;z-index:200;border-radius:0 0 8px 0}
.skip-link:focus{left:0}

/* ---------- eyebrow / tag / badge ---------- */
.eyebrow{
  display:inline-flex;align-items:center;gap:6px;
  font-size:13px;font-weight:600;letter-spacing:.04em;color:var(--primary);
  text-transform:none;
}
.eyebrow::before{content:"";width:16px;height:2px;background:var(--primary);display:inline-block}
.tag-pill{
  display:inline-block;padding:3px 12px;border-radius:999px;
  background:var(--primary-soft);color:var(--primary-dark);
  font-size:12.5px;font-weight:600;
}
.badge-demo{
  display:inline-flex;align-items:center;gap:6px;
  font-size:12px;color:var(--alert);background:var(--alert-soft);
  border:1px solid #ecd6ae;padding:3px 10px;border-radius:6px;font-weight:600;
}
.badge-demo::before{content:"◆";font-size:9px}

/* ---------- header / nav ---------- */
.site-header{
  position:sticky;top:0;z-index:100;
  background:rgba(246,244,239,.92);
  backdrop-filter:saturate(160%) blur(8px);
  border-bottom:1px solid var(--line);
}
.header-bar{display:flex;align-items:center;justify-content:space-between;height:72px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:19px;color:var(--text)}
.brand:hover{text-decoration:none}
.brand-mark{width:34px;height:34px;flex:none}
.brand-sub{font-size:11.5px;font-weight:500;color:var(--text-mute);display:block;letter-spacing:.02em}
.main-nav{display:flex;align-items:center;gap:2px}
.main-nav a{
  padding:10px 14px;border-radius:8px;color:var(--text-soft);font-size:14.5px;font-weight:500;
}
.main-nav a:hover,.main-nav a[aria-current="page"]{
  background:var(--primary-soft);color:var(--primary-dark);text-decoration:none;
}
.nav-toggle{
  display:none;border:1px solid var(--line-strong);background:var(--surface);
  border-radius:8px;padding:8px 10px;
}
.nav-toggle span{display:block;width:20px;height:2px;background:var(--text);margin:4px 0;border-radius:2px}

/* ---------- breadcrumb ---------- */
.breadcrumb{font-size:13px;color:var(--text-mute);padding:16px 0 0}
.breadcrumb a{color:var(--text-mute)}
.breadcrumb a:hover{color:var(--primary)}
.breadcrumb .sep{margin:0 6px;color:var(--line-strong)}

/* ---------- hero ---------- */
.hero{padding:52px 0 40px;border-bottom:1px solid var(--line)}
.hero-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:48px;align-items:center}
.hero h1{font-size:clamp(28px,3.4vw,42px);line-height:1.32;font-weight:800;letter-spacing:-.01em;color:var(--text)}
.hero .lede{margin-top:18px;font-size:17px;color:var(--text-soft);line-height:1.85}
.hero-actions{display:flex;gap:12px;margin-top:26px;flex-wrap:wrap}
.hero-visual{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-lg);padding:20px;box-shadow:var(--shadow)}
.hero-visual figcaption{margin-top:12px;font-size:12.5px;color:var(--text-mute);line-height:1.6}

/* page hero (secondary pages, shorter) */
.page-hero{padding:36px 0 32px;border-bottom:1px solid var(--line)}
.page-hero h1{font-size:clamp(26px,3vw,36px);font-weight:800;line-height:1.3;color:var(--text)}
.page-hero .lede{margin-top:14px;font-size:16px;color:var(--text-soft);max-width:820px}
.page-intro{padding:36px 0;border-bottom:1px solid var(--line)}
.page-intro .intro-body p{margin-bottom:16px;color:var(--text-soft);font-size:15.5px}
.page-intro .intro-body p:last-child{margin-bottom:0}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:11px 20px;border-radius:9px;font-weight:600;font-size:14.5px;
  border:1px solid transparent;
}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-dark);text-decoration:none}
.btn-ghost{background:var(--surface);border-color:var(--line-strong);color:var(--text)}
.btn-ghost:hover{border-color:var(--primary);color:var(--primary);text-decoration:none}

/* ---------- section framing ---------- */
.section{padding:56px 0}
.section-alt{background:var(--surface-alt)}
.section-head{max-width:720px;margin-bottom:32px}
.section-head h2{font-size:clamp(22px,2.4vw,30px);font-weight:800;color:var(--text);line-height:1.35}
.section-head .section-desc{margin-top:10px;font-size:15.5px;color:var(--text-soft)}
.section-foot{margin-top:28px}

/* ---------- overview cards (经营总览示意) ---------- */
.overview-strip{display:flex;justify-content:space-between;align-items:center;margin-bottom:18px;flex-wrap:wrap;gap:10px}
.overview-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:14px}
.overview-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px 16px;box-shadow:var(--shadow-sm)}
.overview-card .oc-label{font-size:13px;color:var(--text-mute);font-weight:600}
.overview-card .oc-value{font-size:23px;font-weight:800;color:var(--text);margin-top:6px}
.overview-card .oc-delta{font-size:12.5px;margin-top:6px;font-weight:600}
.oc-delta.up{color:var(--growth)}
.oc-delta.down{color:var(--risk)}
.oc-delta.mid{color:var(--forecast)}

/* ---------- flagship articles (homepage 8 篇) ---------- */
.flagship-list{display:flex;flex-direction:column;gap:0}
.flagship{
  display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center;
  padding:44px 0;border-bottom:1px solid var(--line);
}
.flagship:last-child{border-bottom:none}
.flagship.reverse .flagship-visual{order:2}
.flagship.reverse .flagship-text{order:1}
.flagship-meta{display:flex;align-items:center;gap:10px;font-size:12.5px;color:var(--text-mute);margin-bottom:12px}
.flagship-text h3{font-size:clamp(19px,2vw,23px);font-weight:800;line-height:1.5;color:var(--text)}
.flagship-text .flagship-body{margin-top:14px;color:var(--text-soft);font-size:15px}
.flagship-text .flagship-body p{margin-bottom:13px}
.flagship-text .flagship-body p:last-child{margin-bottom:0}
.flagship-visual{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-lg);padding:18px;box-shadow:var(--shadow)}
.flagship-visual figcaption{margin-top:10px;font-size:12px;color:var(--text-mute);line-height:1.6}

/* ---------- observation list (欧博官网经营观察) ---------- */
.observation-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.observation-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:var(--shadow-sm)}
.observation-card h3{font-size:16.5px;font-weight:700;line-height:1.5;color:var(--text)}
.observation-card p{margin-top:12px;font-size:14.5px;color:var(--text-soft)}
.observation-card .om-date{font-size:12px;color:var(--text-mute);margin-bottom:8px}

/* ---------- article grid (secondary page 3/4 篇) ---------- */
.article-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.article-grid.cols-4{grid-template-columns:repeat(2,1fr)}
.article-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow-sm);display:flex;flex-direction:column}
.article-card .am-date{font-size:12px;color:var(--text-mute)}
.article-card h3{margin-top:8px;font-size:17px;font-weight:700;line-height:1.5;color:var(--text)}
.article-card .article-body{margin-top:14px;color:var(--text-soft);font-size:14.8px;flex:1}
.article-card .article-body p{margin-bottom:13px}
.article-card .article-body p:last-child{margin-bottom:0}
.article-card .article-tags{margin-top:16px;display:flex;gap:8px;flex-wrap:wrap}

/* ---------- rollup (首页回流二级页文章) ---------- */
.rollup-section{padding:44px 0;border-top:1px solid var(--line)}
.rollup-head{display:flex;justify-content:space-between;align-items:baseline;margin-bottom:20px;flex-wrap:wrap;gap:10px}
.rollup-head h2{font-size:21px;font-weight:800;color:var(--text)}
.rollup-head .rollup-link{font-size:14px;font-weight:600}
.rollup-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.rollup-grid.cols-4{grid-template-columns:repeat(4,1fr)}
.rollup-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px;box-shadow:var(--shadow-sm)}
.rollup-card .rc-date{font-size:11.5px;color:var(--text-mute)}
.rollup-card h4{margin-top:6px;font-size:15px;font-weight:700;line-height:1.5;color:var(--text)}
.rollup-card p{margin-top:10px;font-size:13.5px;color:var(--text-soft)}
.rollup-card a.rc-more{display:inline-block;margin-top:10px;font-size:13px;font-weight:600}

/* ---------- trend grid (2026趋势) ---------- */
.trend-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.trend-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px;box-shadow:var(--shadow-sm)}
.trend-card .tc-num{font-size:12px;font-weight:800;color:var(--forecast);letter-spacing:.06em}
.trend-card h3{margin-top:8px;font-size:15.5px;font-weight:700;color:var(--text);line-height:1.5}
.trend-card p{margin-top:8px;font-size:13.5px;color:var(--text-soft)}

/* ---------- process flow (通用流程条) ---------- */
.flow-strip{display:flex;align-items:center;flex-wrap:wrap;gap:0;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px 20px;box-shadow:var(--shadow-sm)}
.flow-step{display:flex;align-items:center;gap:10px;font-size:13.5px;font-weight:600;color:var(--text)}
.flow-step .step-dot{width:8px;height:8px;border-radius:50%;background:var(--primary);flex:none}
.flow-arrow{margin:0 14px;color:var(--line-strong);font-size:16px}

/* ---------- FAQ ---------- */
.faq-list{border-top:1px solid var(--line)}
.faq-item{border-bottom:1px solid var(--line)}
.faq-item summary{
  display:flex;justify-content:space-between;align-items:center;gap:16px;
  padding:18px 4px;cursor:pointer;font-weight:700;font-size:15.5px;color:var(--text);
  list-style:none;
}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:"+";font-size:20px;color:var(--text-mute);font-weight:400;flex:none}
.faq-item[open] summary::after{content:"–"}
.faq-item .faq-a{padding:0 4px 18px;color:var(--text-soft);font-size:14.8px;max-width:820px}

/* ---------- signal card (驾驶舱异常卡片) ---------- */
.signal-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.signal-card{background:var(--surface);border:1px solid var(--line);border-left:4px solid var(--alert);border-radius:var(--radius);padding:18px;box-shadow:var(--shadow-sm)}
.signal-card.high{border-left-color:var(--risk)}
.signal-card.medium{border-left-color:var(--alert)}
.signal-card.low{border-left-color:var(--forecast)}
.signal-card .sc-metric{font-size:14px;font-weight:800;color:var(--text)}
.signal-card .sc-row{display:flex;justify-content:space-between;font-size:12.8px;color:var(--text-mute);margin-top:8px}
.signal-card .sc-row span:last-child{color:var(--text-soft);font-weight:600}
.signal-card .sc-driver{margin-top:10px;font-size:13px;color:var(--text-soft)}
.signal-card .sc-foot{margin-top:12px;display:flex;justify-content:space-between;align-items:center}
.mat-tag{font-size:11px;font-weight:700;padding:2px 9px;border-radius:999px}
.mat-tag.high{background:var(--risk-soft);color:var(--risk)}
.mat-tag.medium{background:var(--alert-soft);color:var(--alert)}
.mat-tag.low{background:var(--forecast-soft);color:var(--forecast)}

/* ---------- layer stack (驾驶舱信息层级 / semantic layer / foundation model) ---------- */
.layer-stack{display:flex;flex-direction:column;gap:10px}
.layer-row{display:grid;grid-template-columns:120px 1fr;gap:18px;align-items:center;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:14px 18px;box-shadow:var(--shadow-sm)}
.layer-row .lr-index{font-size:12px;font-weight:800;color:var(--primary)}
.layer-row .lr-name{font-size:15px;font-weight:700;color:var(--text)}
.layer-row .lr-desc{font-size:13.5px;color:var(--text-soft);margin-top:4px}

/* ---------- scenario tabs (Scenario Planning demo) ---------- */
.scenario-widget{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-lg);padding:22px;box-shadow:var(--shadow)}
.scenario-tabs{display:flex;gap:8px;flex-wrap:wrap}
.scenario-tab{
  padding:9px 16px;border-radius:8px;border:1px solid var(--line-strong);background:var(--surface);
  font-size:13.5px;font-weight:600;color:var(--text-soft);
}
.scenario-tab[aria-selected="true"]{background:var(--primary);border-color:var(--primary);color:#fff}
.scenario-panel{display:none;margin-top:20px}
.scenario-panel[data-active="true"]{display:block}
.scenario-metrics{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.scenario-metrics .sm-item{background:var(--surface-alt);border:1px solid var(--line);border-radius:var(--radius-sm);padding:14px}
.scenario-metrics .sm-label{font-size:12.5px;color:var(--text-mute);font-weight:600}
.scenario-metrics .sm-value{font-size:20px;font-weight:800;margin-top:6px;color:var(--text)}
.scenario-note{margin-top:16px;font-size:13px;color:var(--text-mute)}

/* ---------- app features ---------- */
.app-feature-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.app-feature{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:20px;text-align:left;box-shadow:var(--shadow-sm)}
.app-feature .af-icon{width:38px;height:38px;margin-bottom:12px}
.app-feature h3{font-size:15px;font-weight:700;color:var(--text)}
.app-feature p{margin-top:8px;font-size:13px;color:var(--text-soft)}

/* ---------- download block ---------- */
.download-panel{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.download-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:22px;text-align:center;box-shadow:var(--shadow-sm)}
.download-card .dl-icon{width:40px;height:40px;margin:0 auto 12px}
.download-card h3{font-size:15.5px;font-weight:700}
.download-card p{margin-top:8px;font-size:13px;color:var(--text-soft)}
.download-note{margin-top:22px;background:var(--surface-alt);border:1px dashed var(--line-strong);border-radius:var(--radius);padding:16px 18px;font-size:13.5px;color:var(--text-soft)}

/* ---------- company / about ---------- */
.about-panel{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:start}
.about-panel .about-body p{margin-bottom:14px;color:var(--text-soft);font-size:15px}
.fact-list{display:flex;flex-direction:column;gap:14px}
.fact-row{display:flex;justify-content:space-between;border-bottom:1px solid var(--line);padding-bottom:12px;font-size:14px}
.fact-row span:first-child{color:var(--text-mute)}
.fact-row span:last-child{font-weight:700;color:var(--text)}

/* ---------- disclaimers ---------- */
.disclaimer-block{background:var(--surface-alt);border:1px solid var(--line);border-radius:var(--radius);padding:20px 22px;font-size:13px;color:var(--text-mute);line-height:1.8}
.disclaimer-block p{margin-bottom:8px}
.disclaimer-block p:last-child{margin-bottom:0}

/* ---------- footer ---------- */
.site-footer{background:var(--primary-dark);color:#dfe7e4;padding:48px 0 24px;margin-top:20px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:32px}
.footer-brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;color:#fff}
.footer-desc{margin-top:14px;font-size:13.5px;color:#b9c7c3;line-height:1.8}
.footer-col h4{font-size:13.5px;font-weight:700;color:#fff;margin-bottom:14px}
.footer-col li{margin-bottom:10px}
.footer-col a{color:#b9c7c3;font-size:13.5px}
.footer-col a:hover{color:#fff}
.footer-bottom{margin-top:36px;padding-top:20px;border-top:1px solid rgba(255,255,255,.12);display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;font-size:12.5px;color:#94a5a0}
.footer-bottom a{color:#94a5a0}
.footer-bottom a:hover{color:#fff}

/* ---------- utility ---------- */
.mt-0{margin-top:0}
.text-center{text-align:center}
.stack-lg > * + *{margin-top:24px}
.divider{height:1px;background:var(--line);margin:44px 0}

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width:1024px){
  .hero-grid{grid-template-columns:1fr}
  .hero-visual{order:-1}
  .overview-grid{grid-template-columns:repeat(3,1fr)}
  .article-grid{grid-template-columns:repeat(2,1fr)}
  .rollup-grid{grid-template-columns:repeat(2,1fr)}
  .rollup-grid.cols-4{grid-template-columns:repeat(2,1fr)}
  .trend-grid{grid-template-columns:repeat(2,1fr)}
  .observation-grid{grid-template-columns:1fr}
  .signal-grid{grid-template-columns:repeat(2,1fr)}
  .app-feature-grid{grid-template-columns:repeat(2,1fr)}
  .download-panel{grid-template-columns:1fr}
  .about-panel{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media (max-width:768px){
  .main-nav{
    position:fixed;inset:72px 0 0 0;background:var(--bg);
    flex-direction:column;align-items:stretch;padding:16px;gap:4px;
    display:none;overflow-y:auto;
  }
  .main-nav.open{display:flex}
  .main-nav a{padding:14px 16px;border-bottom:1px solid var(--line);border-radius:0}
  .nav-toggle{display:block}
  .flagship{grid-template-columns:1fr}
  .flagship.reverse .flagship-visual,.flagship.reverse .flagship-text{order:unset}
  .article-grid,.article-grid.cols-4{grid-template-columns:1fr}
  .rollup-grid,.rollup-grid.cols-4{grid-template-columns:1fr}
  .trend-grid{grid-template-columns:1fr}
  .overview-grid{grid-template-columns:repeat(2,1fr)}
  .signal-grid{grid-template-columns:1fr}
  .app-feature-grid{grid-template-columns:1fr 1fr}
  .scenario-metrics{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
}
@media (max-width:430px){
  .container{padding:0 16px}
  .hero{padding:36px 0 28px}
  .section{padding:40px 0}
  .overview-grid{grid-template-columns:1fr 1fr}
  .app-feature-grid{grid-template-columns:1fr}
}