/* ============================================================
   青岛博威特建材有限公司 · 高端品牌官网
   Design System v1.0 — 深色奢华 · 金色点缀 · 大图留白
   ============================================================ */

:root{
  --ink:#0c0d0f;
  --ink-2:#121417;
  --ink-3:#1a1d22;
  --line:rgba(255,255,255,.08);
  --gold:#c8a45c;
  --gold-2:#e4c98a;
  --paper:#f4f1ea;
  --paper-2:#ffffff;
  --gray:#9aa0a8;
  --gray-2:#6b7178;
  --serif:"Noto Serif SC","Songti SC","SimSun",serif;
  --sans:"Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --ease:cubic-bezier(.22,.61,.36,1);
}

*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:var(--sans);
  background:var(--ink);
  color:var(--paper);
  line-height:1.8;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
img{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
ul{list-style:none}

.wrap{width:min(1200px,92%);margin:0 auto}
.section{padding:110px 0;position:relative}
.section--light{background:var(--paper);color:var(--ink-2)}
.section--gray{background:#f0ede6;color:var(--ink-2)}

/* ---------- 标题系统 ---------- */
.kicker{
  font-size:13px;letter-spacing:.42em;text-transform:uppercase;
  color:var(--gold);margin-bottom:14px;font-weight:600;
}
.kicker--dark{color:var(--gold)}
h1,h2,h3,.title-serif{font-family:var(--serif);font-weight:600}
.h2{font-size:clamp(26px,3.6vw,44px);line-height:1.35;letter-spacing:.04em}
.h3{font-size:clamp(18px,2vw,24px);letter-spacing:.04em}
.sub{color:var(--gray);font-size:15px;max-width:640px;margin-top:16px}
.section--light .sub{color:#5d636b}
.sec-head{text-align:center;margin-bottom:64px}
.sec-head .sub{margin-left:auto;margin-right:auto}
.divider{width:56px;height:1px;background:var(--gold);margin:22px auto 0}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;gap:10px;
  padding:14px 34px;border:1px solid var(--gold);
  color:var(--gold);font-size:14px;letter-spacing:.14em;
  transition:all .35s var(--ease);cursor:pointer;background:transparent;
}
.btn:hover{background:var(--gold);color:#0c0d0f}
.btn--solid{background:var(--gold);color:#0c0d0f}
.btn--solid:hover{background:var(--gold-2);border-color:var(--gold-2)}
.btn--light{color:var(--ink-2);border-color:var(--ink-2)}
.btn--light:hover{background:var(--ink-2);color:var(--paper)}

/* ---------- 顶部导航 ---------- */
.nav{
  position:fixed;inset:0 0 auto 0;z-index:100;
  padding:26px 0;transition:all .4s var(--ease);
  background:linear-gradient(rgba(12,13,15,.72),transparent);
}
.nav.scrolled{background:rgba(12,13,15,.96);padding:16px 0;backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.nav-inner{display:flex;align-items:center;justify-content:space-between}
.logo{display:flex;align-items:center;gap:14px}
.logo-mark{
  width:44px;height:44px;border:1px solid var(--gold);
  display:flex;align-items:center;justify-content:center;
  font-family:var(--serif);font-weight:700;color:var(--gold);font-size:18px;
  letter-spacing:1px;
}
.logo-name{font-family:var(--serif);font-size:20px;letter-spacing:.12em;line-height:1.2}
.logo-name small{display:block;font-size:10px;color:var(--gold);letter-spacing:.34em;margin-top:2px;font-family:var(--sans);font-weight:400}
.nav-links{display:flex;gap:38px;align-items:center}
.nav-links a{font-size:14px;letter-spacing:.12em;color:rgba(244,241,234,.82);position:relative;padding:6px 0;transition:color .3s}
.nav-links a::after{content:"";position:absolute;left:0;bottom:0;width:0;height:1px;background:var(--gold);transition:width .35s var(--ease)}
.nav-links a:hover,.nav-links a.active{color:var(--gold-2)}
.nav-links a:hover::after,.nav-links a.active::after{width:100%}
.nav-cta{border:1px solid var(--gold);padding:10px 24px;color:var(--gold);font-size:13px;letter-spacing:.14em;transition:all .3s}
.nav-cta:hover{background:var(--gold);color:#0c0d0f}
.nav-burger{display:none;flex-direction:column;gap:5px;cursor:pointer;background:none;border:none}
.nav-burger span{width:26px;height:1.5px;background:var(--paper);transition:all .3s}

/* ---------- Hero ---------- */
.hero{position:relative;min-height:100vh;display:flex;align-items:center;overflow:hidden}
.hero-bg{position:absolute;inset:0}
.hero-bg img{width:100%;height:100%;object-fit:cover;transform:scale(1.06);animation:heroZoom 14s var(--ease) forwards}
@keyframes heroZoom{to{transform:scale(1)}}
.hero-bg::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(12,13,15,.55) 0%,rgba(12,13,15,.35) 40%,var(--ink) 100%)}
.hero-inner{position:relative;z-index:2;width:min(1200px,92%);margin:0 auto;padding-top:60px}
.hero .kicker{animation:fadeUp .9s var(--ease) .1s both}
.hero h1{
  font-size:clamp(38px,6vw,74px);line-height:1.22;letter-spacing:.06em;
  margin:8px 0 6px;animation:fadeUp .9s var(--ease) .25s both;
}
.hero h1 .gold{color:var(--gold)}
.hero .hero-sub{font-size:clamp(15px,1.6vw,19px);color:rgba(244,241,234,.85);max-width:560px;margin-top:18px;animation:fadeUp .9s var(--ease) .4s both}
.hero-actions{display:flex;gap:18px;margin-top:40px;animation:fadeUp .9s var(--ease) .55s both}
@keyframes fadeUp{from{opacity:0;transform:translateY(26px)}to{opacity:1;transform:none}}
.hero-scroll{
  position:absolute;bottom:34px;left:50%;transform:translateX(-50%);
  font-size:11px;letter-spacing:.3em;color:rgba(244,241,234,.5);
  display:flex;flex-direction:column;align-items:center;gap:10px;z-index:2;
}
.hero-scroll::after{content:"";width:1px;height:44px;background:linear-gradient(var(--gold),transparent);animation:scrollLine 2s infinite}
@keyframes scrollLine{0%{transform:scaleY(0);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}51%{transform-origin:bottom}100%{transform:scaleY(0);transform-origin:bottom}}

/* ---------- 数据统计 ---------- */
.stats{border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:64px 0}
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:30px;text-align:center}
.stat-num{font-family:var(--serif);font-size:clamp(34px,4vw,56px);color:var(--gold-2);line-height:1.1}
.stat-label{font-size:13px;letter-spacing:.18em;color:var(--gray);margin-top:10px}

/* ---------- 品牌主张 ---------- */
.statement{text-align:center}
.statement .big{
  font-family:var(--serif);font-size:clamp(22px,2.8vw,34px);line-height:1.7;letter-spacing:.06em;
  max-width:900px;margin:8px auto 0;
}
.statement .big .gold{color:var(--gold)}
.features{display:grid;grid-template-columns:repeat(3,1fr);gap:30px;margin-top:80px}
.feature{border:1px solid var(--line);padding:42px 34px;transition:all .4s var(--ease);position:relative;overflow:hidden}
.feature::before{content:"";position:absolute;inset:0;background:linear-gradient(135deg,rgba(200,164,92,.08),transparent 60%);opacity:0;transition:opacity .4s}
.feature:hover{transform:translateY(-6px);border-color:rgba(200,164,92,.4)}
.feature:hover::before{opacity:1}
.feature .feat-no{font-family:var(--serif);color:var(--gold);font-size:13px;letter-spacing:.3em}
.feature h3{margin:14px 0 10px;font-size:20px}
.feature p{color:var(--gray);font-size:14px;line-height:1.9}

/* ---------- 产品概览 ---------- */
.products-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:2px;background:var(--line)}
.product-card{background:var(--ink);padding:46px 30px;transition:all .4s var(--ease);position:relative;min-height:270px;display:flex;flex-direction:column;justify-content:flex-end}
.product-card:hover{background:var(--ink-3)}
.product-card .p-no{font-size:12px;letter-spacing:.28em;color:var(--gold);margin-bottom:16px}
.product-card h3{font-size:19px;margin-bottom:10px}
.product-card p{color:var(--gray);font-size:13.5px;line-height:1.85;opacity:0;max-height:0;transition:all .45s var(--ease)}
.product-card:hover p{opacity:1;max-height:140px}
.product-card .p-arrow{position:absolute;top:34px;right:30px;color:var(--gold);font-size:22px;opacity:.5;transition:opacity .3s}
.product-card:hover .p-arrow{opacity:1}
.section--light .product-card{background:var(--paper-2)}
.section--light .product-card p{color:#5d636b}
.section--light .products-grid{background:#d8d3c8}
.section--light .product-card:hover{background:#fff}

/* ---------- 案例 ---------- */
.cases-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.case-card{position:relative;overflow:hidden;aspect-ratio:4/3;cursor:pointer}
.case-card img{width:100%;height:100%;object-fit:cover;transition:transform 1.2s var(--ease)}
.case-card:hover img{transform:scale(1.08)}
.case-card .case-mask{position:absolute;inset:0;background:linear-gradient(180deg,transparent 40%,rgba(10,11,13,.88) 100%);opacity:.85;transition:opacity .4s;display:flex;flex-direction:column;justify-content:flex-end;padding:26px}
.case-card:hover .case-mask{opacity:1}
.case-card .case-tag{font-size:11px;letter-spacing:.24em;color:var(--gold);margin-bottom:6px}
.case-card h3{font-size:18px}

/* ---------- 资质 ---------- */
.certs{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.cert-card{background:#fff;padding:16px;box-shadow:0 6px 30px rgba(0,0,0,.16);transition:all .4s var(--ease)}
.cert-card:hover{transform:translateY(-6px);box-shadow:0 18px 46px rgba(0,0,0,.28)}
.cert-card img{aspect-ratio:3/4;object-fit:cover;width:100%}
.cert-card p{font-size:12.5px;color:#4a4f55;margin-top:12px;text-align:center;line-height:1.6}

/* ---------- 磨匠团 ---------- */
.team-wrap{display:grid;grid-template-columns:1.1fr 1fr;gap:70px;align-items:center}
.team-img{position:relative}
.team-img img{width:100%;max-height:520px;object-fit:cover}
.team-img::after{content:"";position:absolute;inset:0;border:1px solid rgba(200,164,92,.5);transform:translate(16px,16px);z-index:-1}
.team-list{margin-top:34px;display:grid;gap:14px}
.team-list li{display:flex;gap:14px;align-items:flex-start;color:var(--gray);font-size:15px}
.team-list li::before{content:"◆";color:var(--gold);font-size:11px;margin-top:7px}

/* ---------- CTA ---------- */
.cta{position:relative;overflow:hidden;text-align:center;padding:130px 0}
.cta-bg{position:absolute;inset:0}
.cta-bg img{width:100%;height:100%;object-fit:cover}
.cta-bg::after{content:"";position:absolute;inset:0;background:rgba(12,13,15,.82)}
.cta-inner{position:relative;z-index:2}
.cta h2{font-size:clamp(26px,3.4vw,44px);letter-spacing:.05em}
.cta p{color:rgba(244,241,234,.75);margin:18px auto 40px;max-width:520px;font-size:15px}

/* ---------- 页脚 ---------- */
.footer{border-top:1px solid var(--line);padding:70px 0 34px;background:#0a0b0d}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.2fr;gap:50px;margin-bottom:60px}
.footer h4{font-family:var(--serif);font-size:17px;letter-spacing:.1em;margin-bottom:22px;color:var(--gold)}
.footer p,.footer li{color:var(--gray);font-size:13.5px;line-height:2.1}
.footer a:hover{color:var(--gold-2)}
.footer-bottom{border-top:1px solid var(--line);padding-top:26px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;font-size:12px;color:var(--gray-2)}

/* ---------- 内页 Hero ---------- */
.page-hero{position:relative;padding:190px 0 90px;overflow:hidden;border-bottom:1px solid var(--line)}
.page-hero .bg{position:absolute;inset:0}
.page-hero .bg img{width:100%;height:100%;object-fit:cover}
.page-hero .bg::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(12,13,15,.72),rgba(12,13,15,.9))}
.page-hero .wrap{position:relative;z-index:2}
.page-hero h1{font-size:clamp(30px,4vw,50px);letter-spacing:.08em;margin-top:6px}
.page-hero .crumbs{font-size:12px;letter-spacing:.2em;color:var(--gray);margin-top:18px}
.page-hero .crumbs .gold{color:var(--gold)}

/* ---------- 关于页 ---------- */
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:80px;align-items:start}
.about-txt p{color:var(--gray);font-size:15px;line-height:2.1;margin-bottom:20px}
.section--light .about-txt p{color:#4a4f55}
.timeline{position:relative;padding-left:34px;margin-top:40px}
.timeline::before{content:"";position:absolute;left:8px;top:6px;bottom:6px;width:1px;background:var(--gold)}
.timeline li{position:relative;padding-bottom:34px}
.timeline li::before{content:"";position:absolute;left:-31px;top:8px;width:9px;height:9px;background:var(--gold);transform:rotate(45deg)}
.timeline .t-year{font-family:var(--serif);color:var(--gold);font-size:15px;letter-spacing:.14em}
.timeline .t-txt{font-size:14.5px;color:var(--gray);margin-top:6px;line-height:1.9}

/* ---------- 产品页 ---------- */
.prod-block{border:1px solid var(--line);padding:54px 50px;margin-bottom:28px;transition:border-color .4s}
.prod-block:hover{border-color:rgba(200,164,92,.45)}
.prod-block h3{font-size:22px;margin-bottom:6px}
.prod-block .en{color:var(--gold);font-size:12px;letter-spacing:.3em;margin-bottom:18px}
.prod-block .tags{display:flex;flex-wrap:wrap;gap:10px;margin:18px 0}
.prod-block .tags span{border:1px solid var(--line);padding:5px 16px;font-size:12px;color:var(--gray)}
.prod-block p{color:var(--gray);font-size:14.5px;line-height:2}

/* ---------- 联系页 ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1.2fr;gap:70px}
.contact-info li{display:flex;gap:18px;padding:22px 0;border-bottom:1px solid var(--line)}
.contact-info li:last-child{border-bottom:none}
.contact-info .ic{color:var(--gold);font-family:var(--serif);font-size:13px;letter-spacing:.2em;min-width:52px}
.contact-info .tx b{display:block;font-size:15px;font-weight:500;letter-spacing:.05em}
.contact-info .tx span{color:var(--gray);font-size:13.5px}
.form{display:grid;gap:18px}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.form input,.form textarea,.form select{
  width:100%;background:transparent;border:1px solid var(--line);color:var(--paper);
  padding:15px 18px;font-size:14px;font-family:var(--sans);transition:border-color .3s;outline:none;
}
.form input:focus,.form textarea:focus,.form select:focus{border-color:var(--gold)}
.form textarea{min-height:130px;resize:vertical}
.form ::placeholder{color:var(--gray-2)}
.form select option{background:var(--ink-2)}

/* ---------- 动画 ---------- */
.reveal{opacity:0;transform:translateY(34px);transition:opacity .9s var(--ease),transform .9s var(--ease)}
.reveal.in{opacity:1;transform:none}
.reveal-d1{transition-delay:.12s}
.reveal-d2{transition-delay:.24s}
.reveal-d3{transition-delay:.36s}

/* ---------- 移动端 ---------- */
@media(max-width:960px){
  .nav-links{position:fixed;inset:0;background:rgba(12,13,15,.99);flex-direction:column;gap:30px;justify-content:center;display:none;z-index:99}
  .nav-links.open{display:flex}
  .nav-burger{display:flex;z-index:100}
  .stats-grid{grid-template-columns:repeat(2,1fr);gap:40px}
  .features{grid-template-columns:1fr}
  .products-grid{grid-template-columns:repeat(2,1fr)}
  .cases-grid{grid-template-columns:1fr 1fr}
  .certs{grid-template-columns:repeat(2,1fr)}
  .team-wrap,.about-grid,.contact-grid{grid-template-columns:1fr;gap:50px}
  .footer-grid{grid-template-columns:1fr 1fr}
  .form-row{grid-template-columns:1fr}
  .hero-actions{flex-direction:column;align-items:flex-start}
  .section{padding:80px 0}
}
@media(max-width:560px){
  .products-grid{grid-template-columns:1fr}
  .cases-grid{grid-template-columns:1fr}
  .certs{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .prod-block{padding:38px 26px}
}