:root{
  --brand:#1f4e5f;
  --brand-dark:#163a47;
  --brand-light:#2c6b80;
  --accent:#c8a15a;
  --accent-dark:#a9853f;
  --bg:#f6f8f9;
  --surface:#ffffff;
  --ink:#1d262b;
  --muted:#5a6b70;
  --line:#e2e9ec;
  --radius:12px;
  --shadow:0 1px 4px rgba(0,0,0,.06),0 8px 24px rgba(31,78,95,.06);
  --maxw:1180px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:"Microsoft YaHei","PingFang SC","Hiragino Sans GB",sans-serif;
  background:var(--bg);color:var(--ink);line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:var(--brand);text-decoration:none}
a:hover{color:var(--accent-dark)}
h1,h2,h3,h4{color:var(--brand-dark);line-height:1.3;font-weight:700}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ===== Nav ===== */
.nav{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.92);backdrop-filter:blur(8px);
  border-bottom:1px solid var(--line);
  transition:background .3s,box-shadow .3s;
}
.nav.scrolled{box-shadow:0 2px 12px rgba(0,0,0,.08)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;color:var(--brand-dark);font-size:18px}
.brand img{height:34px;width:auto}
.nav-links{display:flex;gap:26px;list-style:none;font-size:15px}
.nav-links a{color:var(--ink);position:relative}
.nav-links a::after{content:"";position:absolute;left:0;bottom:-6px;width:0;height:2px;background:var(--accent);transition:width .25s}
.nav-links a:hover::after,.nav-links a.active::after{width:100%}
.nav-cta{background:var(--accent);color:#3a2c08;padding:9px 18px;border-radius:30px;font-weight:600;font-size:14px}
.nav-cta:hover{background:var(--accent-dark);color:#2b2006}
.nav-toggle{display:none;background:none;border:none;font-size:26px;color:var(--brand-dark);cursor:pointer}

/* ===== Hero ===== */
.hero{
  position:relative;min-height:78vh;display:flex;align-items:center;justify-content:center;
  color:#fff;text-align:center;overflow:hidden;
}
.hero-bg{position:absolute;inset:0;background:linear-gradient(135deg,rgba(22,58,71,.92),rgba(44,107,128,.82)),url('../images/01-hero.jpg') center/cover no-repeat;transform:scale(1.05)}
.hero-inner{position:relative;z-index:2;padding:40px 20px;max-width:860px}
.hero h1{color:#fff;font-size:clamp(28px,5vw,46px);margin-bottom:16px;text-shadow:0 2px 16px rgba(0,0,0,.3)}
.hero p.lead{font-size:clamp(15px,2.4vw,20px);color:#eaf3f6;margin-bottom:28px}
.hero-tags{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;margin-bottom:30px}
.hero-tags span{background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.3);padding:6px 14px;border-radius:20px;font-size:13px}
.btn{display:inline-block;padding:13px 30px;border-radius:30px;font-weight:600;font-size:15px;transition:transform .15s,box-shadow .2s}
.btn-primary{background:var(--accent);color:#3a2c08}
.btn-primary:hover{background:var(--accent-dark);transform:translateY(-2px);box-shadow:0 8px 20px rgba(200,161,90,.4)}
.btn-ghost{border:1.5px solid #fff;color:#fff;margin-left:12px}
.btn-ghost:hover{background:rgba(255,255,255,.14);color:#fff}

/* ===== Sections ===== */
section{padding:64px 0}
.section-head{text-align:center;max-width:760px;margin:0 auto 44px}
.section-head h2{font-size:clamp(24px,4vw,34px);margin-bottom:12px}
.section-head h2 .bar{display:inline-block;width:42px;height:4px;background:var(--accent);border-radius:2px;vertical-align:middle;margin-right:12px}
.section-head p{color:var(--muted);font-size:16px}

/* advantage cards */
.grid{display:grid;gap:22px}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow);transition:transform .2s,box-shadow .2s}
.card:hover{transform:translateY(-4px);box-shadow:0 12px 30px rgba(31,78,95,.12)}
.card .ico{font-size:30px;margin-bottom:12px}
.card h3{font-size:19px;margin-bottom:10px}
.card p{color:var(--muted);font-size:14.5px}
.card .num{font-size:30px;font-weight:800;color:var(--accent);line-height:1}
.card .num small{font-size:14px;color:var(--muted);font-weight:400;margin-left:4px}

/* product / case image cards */
.img-card{border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);background:var(--surface)}
.img-card img{width:100%;height:220px;object-fit:cover}
.img-card .body{padding:18px}
.img-card .body h3{font-size:17px;margin-bottom:6px}
.img-card .body p{color:var(--muted);font-size:13.5px}

/* stats strip */
.stats{background:var(--brand-dark);color:#fff}
.stats .grid-4{grid-template-columns:repeat(4,1fr);text-align:center}
.stats .num{font-size:34px;font-weight:800;color:var(--accent)}
.stats p{color:#cfe0e5;font-size:14px;margin-top:4px}

/* FAQ */
.faq-item{border:1px solid var(--line);border-radius:var(--radius);margin-bottom:12px;background:var(--surface);overflow:hidden}
.faq-q{padding:18px 22px;cursor:pointer;font-weight:600;color:var(--brand-dark);display:flex;justify-content:space-between;align-items:center;font-size:16px}
.faq-q .plus{transition:transform .25s;color:var(--accent);font-size:20px}
.faq-item.open .faq-q .plus{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .3s ease;padding:0 22px;color:var(--muted);font-size:14.5px}
.faq-item.open .faq-a{max-height:400px;padding:0 22px 18px}

/* about */
.about-wrap{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center}
.about-wrap img{border-radius:var(--radius);box-shadow:var(--shadow)}
.about-text h2{font-size:28px;margin-bottom:16px}
.about-text p{color:var(--muted);margin-bottom:14px}
.fact-box{background:#eef5f7;border-left:4px solid var(--accent);border-radius:8px;padding:16px 18px;font-size:14.5px;color:var(--ink)}
.fact-box strong{color:var(--brand-dark)}

/* contact */
.contact-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:36px}
.contact-info p{margin-bottom:14px;font-size:15px}
.contact-info .label{font-weight:600;color:var(--brand-dark);display:inline-block;min-width:84px}
.map-placeholder{background:linear-gradient(135deg,#e8f0f2,#d6e4e9);border-radius:var(--radius);min-height:280px;display:flex;align-items:center;justify-content:center;color:var(--muted);text-align:center;padding:20px;border:1px dashed var(--brand-light)}

/* footer */
footer{background:var(--brand-dark);color:#bcd2d8;padding:44px 0 26px;font-size:14px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:30px;margin-bottom:26px}
footer h4{color:#fff;font-size:16px;margin-bottom:14px}
footer a{color:#bcd2d8;display:block;margin-bottom:8px;font-size:13.5px}
footer a:hover{color:var(--accent)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.12);padding-top:18px;text-align:center;color:#8fb0b9;font-size:12.5px}
.footer-bottom a{display:inline;color:#8fb0b9}

/* news / articles list */
.post-card{display:grid;grid-template-columns:200px 1fr;gap:20px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;margin-bottom:20px;box-shadow:var(--shadow)}
.post-card .meta{background:var(--brand);color:#fff;padding:18px;display:flex;flex-direction:column;justify-content:center;text-align:center}
.post-card .meta .d{font-size:22px;font-weight:800}
.post-card .meta .m{font-size:13px;opacity:.85}
.post-card .body{padding:20px 22px}
.post-card .body h3{font-size:18px;margin-bottom:8px}
.post-card .body p{color:var(--muted);font-size:14px}
.tag{display:inline-block;background:#eef5f7;color:var(--brand);font-size:12px;padding:3px 10px;border-radius:12px;margin-right:6px;margin-bottom:6px}

/* breadcrumb */
.crumb{font-size:13px;color:var(--muted);padding:14px 0}
.crumb a{color:var(--muted)}

/* reveal animation */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .6s ease,transform .6s ease}
.reveal.in{opacity:1;transform:none}

/* gallery (4-col product detail grid) */
.grid-4{grid-template-columns:repeat(4,1fr)}
.gallery .img-card img{height:172px}
.gallery .img-card .body{padding:12px 14px}
.gallery .img-card .body h3{font-size:15px;margin-bottom:2px}

/* responsive */
/* ---- 平板 / 大手机：≤900px ---- */
@media(max-width:900px){
  section{padding:52px 0}
  .grid-3,.grid-4{grid-template-columns:1fr 1fr}
  .about-wrap,.contact-grid,.footer-grid,.grid-2{grid-template-columns:1fr}
  .post-card{grid-template-columns:1fr}
  .stats .grid-4{grid-template-columns:1fr}
  .nav-links{display:none;position:absolute;top:60px;left:0;right:0;background:#fff;flex-direction:column;padding:14px 24px;gap:4px;box-shadow:0 8px 20px rgba(0,0,0,.1)}
  .nav-links.show{display:flex}
  .nav-links a{padding:10px 0;font-size:16px;border-bottom:1px solid var(--line)}
  .nav-links li:last-child a{border-bottom:none}
  .nav-toggle{display:block;order:3}
  .nav-cta{order:2;margin-left:auto}
}
/* ---- 手机：≤768px ---- */
@media(max-width:768px){
  section{padding:44px 0}
  .section-head{margin:0 auto 32px}
  .section-head h2{font-size:23px}
  .hero{min-height:auto;padding:64px 0}
  .hero-inner{padding:32px 18px}
  .hero p.lead{font-size:15px;margin-bottom:22px}
  .hero-tags span{font-size:12px;padding:5px 11px}
  .nav-inner{height:60px}
  .brand{font-size:16px}
  .brand img{height:30px}
  .nav-cta{padding:7px 13px;font-size:12px;white-space:nowrap}
  .card{padding:22px}
  .card p{font-size:14px}
  .img-card img{height:190px}
  .gallery .img-card img{height:150px}
  /* 数据条 2×2，比单列更紧凑 */
  .stats .grid-4{grid-template-columns:1fr 1fr;gap:18px}
  .stats .num{font-size:30px}
  /* 文章/新闻卡片：日期块改为横排 */
  .post-card .meta{flex-direction:row;justify-content:flex-start;gap:8px;padding:14px 18px;text-align:left}
  .post-card .meta .d{font-size:20px}
  .post-card .body h3{font-size:17px}
  .post-card .body p{font-size:13.5px}
  .faq-q{font-size:15px;padding:16px 18px}
  .faq-a{font-size:14px}
  footer{padding:36px 0 22px}
  footer h4{font-size:15px}
  .footer-grid{gap:22px}
}
/* ---- 小手机：≤480px ---- */
@media(max-width:480px){
  .container{padding:0 16px}
  .hero h1{font-size:25px}
  .hero p.lead{font-size:14px}
  .hero .btn{display:block;width:100%;max-width:300px;margin:0 auto 12px;box-sizing:border-box}
  .hero .btn-ghost{margin-left:0}
  .section-head p{font-size:14px}
  .card{padding:18px}
  .card h3{font-size:17px}
  .img-card img{height:170px}
  .img-card .body h3{font-size:16px}
  .grid-3,.grid-4{grid-template-columns:1fr}
  .stats .grid-4{grid-template-columns:1fr 1fr}
  .contact-info .label{min-width:0;display:block;margin-bottom:2px}
  .tag{font-size:11px}
  .footer-bottom{font-size:11.5px;line-height:1.7}
  .gallery .img-card img{height:130px}
}