/* ===== 基础变量与重置 ===== */
:root{
  --primary:#143d6b;
  --primary-2:#1e5499;
  --accent:#c79a4b;
  --accent-2:#e3b865;
  --ink:#1f2733;
  --muted:#5b6675;
  --line:#e6eaf0;
  --bg:#ffffff;
  --bg-alt:#f5f8fc;
  --radius:14px;
  --shadow:0 10px 30px rgba(20,61,107,.08);
  --maxw:1140px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:"PingFang SC","Microsoft YaHei","Hiragino Sans GB",system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;
  color:var(--ink);
  background:var(--bg);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 22px}

/* ===== 顶部导航 ===== */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.92);
  backdrop-filter:saturate(160%) blur(10px);
  border-bottom:1px solid var(--line);
}
.nav-wrap{display:flex;align-items:center;justify-content:space-between;height:68px}
.brand{display:flex;align-items:center;gap:12px;color:var(--primary)}
.brand-mark{color:var(--accent);display:flex}
.brand-text{display:flex;flex-direction:column;line-height:1.15}
.brand-text strong{font-size:15px;letter-spacing:.3px;line-height:1.2;word-break:break-word}
.brand-text small{font-size:10px;letter-spacing:2px;color:var(--muted)}
.nav{display:flex;gap:30px}
.nav a{font-size:15px;color:var(--ink);position:relative;padding:6px 0;transition:color .2s}
.nav a::after{content:"";position:absolute;left:0;bottom:0;width:0;height:2px;background:var(--accent);transition:width .25s}
.nav a:hover{color:var(--primary)}
.nav a:hover::after{width:100%}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:8px}
.nav-toggle span{width:24px;height:2px;background:var(--ink);border-radius:2px;transition:.3s}

/* ===== 按钮 ===== */
.btn{display:inline-block;padding:13px 28px;border-radius:999px;font-size:15px;font-weight:600;cursor:pointer;border:1.5px solid transparent;transition:transform .15s,box-shadow .2s,background .2s}
.btn-primary{background:linear-gradient(135deg,var(--primary),var(--primary-2));color:#fff;box-shadow:0 8px 20px rgba(20,61,107,.25)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 12px 26px rgba(20,61,107,.32)}
.btn-ghost{border-color:rgba(255,255,255,.7);color:#fff}
.btn-ghost:hover{background:rgba(255,255,255,.12)}

/* ===== Hero ===== */
.hero{position:relative;color:#fff;overflow:hidden}
.hero-bg{position:absolute;inset:0;background:
  radial-gradient(1200px 500px at 80% -10%,rgba(199,154,75,.45),transparent 60%),
  linear-gradient(135deg,#0e2c52 0%,#143d6b 45%,#1e5499 100%)}
.hero-bg::after{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.04) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.04) 1px,transparent 1px);background-size:46px 46px;mask:radial-gradient(900px 600px at 70% 30%,#000,transparent)}
.hero-inner{position:relative;padding:96px 22px 72px;max-width:var(--maxw);margin:0 auto}
.hero-eyebrow{letter-spacing:4px;font-size:13px;text-transform:uppercase;color:var(--accent-2);margin-bottom:18px}
.hero-title{font-size:clamp(30px,5vw,52px);line-height:1.2;font-weight:800;letter-spacing:1px}
.hero-sub{margin:22px 0 32px;max-width:620px;font-size:17px;color:rgba(255,255,255,.86)}
.hero-actions{display:flex;gap:16px;flex-wrap:wrap}
.hero-stats{list-style:none;display:flex;flex-wrap:wrap;gap:40px;margin-top:54px;padding-top:34px;border-top:1px solid rgba(255,255,255,.18)}
.hero-stats li{display:flex;flex-direction:column}
.hero-stats strong{font-size:26px;font-weight:800;color:#fff}
.hero-stats span{font-size:13px;color:rgba(255,255,255,.75);letter-spacing:1px}

/* ===== 通用区块 ===== */
.section{padding:84px 0}
.section-alt{background:var(--bg-alt)}
.section-head{text-align:center;max-width:720px;margin:0 auto 52px}
.kicker{display:inline-block;font-size:12px;letter-spacing:3px;color:var(--accent);font-weight:700;margin-bottom:10px}
.section-head h2{font-size:clamp(26px,3.4vw,36px);color:var(--primary);font-weight:800;letter-spacing:1px}
.section-head p{margin-top:12px;color:var(--muted);font-size:16px}

/* ===== 关于 ===== */
.about-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:40px;align-items:start}
.about-text p{margin-bottom:18px;font-size:16px;color:#36404e}
.about-text strong{color:var(--primary)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:30px}
.facts h3{color:var(--primary);font-size:18px;margin-bottom:16px}
.facts dl{display:flex;flex-direction:column;gap:0}
.facts dl > div{display:flex;justify-content:space-between;gap:14px;padding:11px 0;border-bottom:1px dashed var(--line);font-size:14px}
.facts dl > div:last-child{border-bottom:0}
.facts dt{color:var(--muted);flex-shrink:0}
.facts dd{text-align:right;font-weight:600;color:var(--ink)}

/* ===== 业务卡片 ===== */
.biz-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.biz-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px 24px;transition:transform .2s,box-shadow .2s,border-color .2s}
.biz-card:hover{transform:translateY(-6px);box-shadow:var(--shadow);border-color:var(--accent)}
.biz-icon{font-size:30px;margin-bottom:14px}
.biz-card h3{font-size:17px;color:var(--primary);margin-bottom:8px}
.biz-card p{font-size:14px;color:var(--muted)}

/* ===== 优势 ===== */
.adv-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.adv-item{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:30px 26px;position:relative;overflow:hidden}
.adv-item::before{content:"";position:absolute;left:0;top:0;width:100%;height:4px;background:linear-gradient(90deg,var(--accent),var(--accent-2))}
.adv-num{font-size:34px;font-weight:800;color:var(--bg-alt);-webkit-text-stroke:1px var(--accent);display:block;margin-bottom:10px}
.adv-item h3{font-size:18px;color:var(--primary);margin-bottom:8px}
.adv-item p{font-size:14px;color:var(--muted)}

/* ===== 联系 ===== */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:32px}
.contact-info h3,.contact-form h3{color:var(--primary);font-size:19px;margin-bottom:18px}
.info-list{list-style:none;display:flex;flex-direction:column;gap:14px}
.info-list li{font-size:15px;color:#36404e;display:flex;gap:12px;align-items:flex-start}
.info-list li span{flex-shrink:0;font-weight:700;color:var(--primary);min-width:78px}
.info-note{margin-top:20px;font-size:13px;color:var(--muted);background:var(--bg-alt);padding:14px 16px;border-radius:10px}
.field{margin-bottom:16px}
.field label{display:block;font-size:14px;color:var(--ink);margin-bottom:7px;font-weight:600}
.field input,.field textarea{width:100%;padding:12px 14px;border:1px solid var(--line);border-radius:10px;font-size:15px;font-family:inherit;color:var(--ink);transition:border-color .2s,box-shadow .2s;background:#fbfdff}
.field input:focus,.field textarea:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px rgba(199,154,75,.15)}
.form-feedback{margin-top:12px;font-size:14px;min-height:20px}
.form-feedback.ok{color:#1d7a4d}
.form-feedback.err{color:#c0392b}

/* ===== 页脚 ===== */
.site-footer{background:#0e2c52;color:#cdd8e6}
.footer-inner{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:20px;padding:42px 22px}
.footer-brand strong{font-size:16px;color:#fff;letter-spacing:.5px;word-break:break-word}
.footer-brand p{font-size:13px;color:#9fb1c6;margin-top:6px}
.footer-nav{display:flex;gap:26px;flex-wrap:wrap}
.footer-nav a{font-size:14px;color:#cdd8e6;transition:color .2s}
.footer-nav a:hover{color:var(--accent-2)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding:18px 0;font-size:12px;color:#8ea2ba;text-align:center}
.footer-bottom .disclaimer{margin-top:6px;color:#6f86a3}

/* ===== 返回顶部 ===== */
.to-top{position:fixed;right:22px;bottom:22px;width:46px;height:46px;border-radius:50%;border:0;background:var(--primary);color:#fff;font-size:20px;cursor:pointer;box-shadow:0 8px 20px rgba(20,61,107,.3);opacity:0;visibility:hidden;transition:.25s;z-index:40}
.to-top.show{opacity:1;visibility:visible}
.to-top:hover{background:var(--primary-2)}

/* ===== 响应式 ===== */
@media (max-width:900px){
  .about-grid{grid-template-columns:1fr}
  .biz-grid{grid-template-columns:repeat(2,1fr)}
  .adv-grid{grid-template-columns:repeat(2,1fr)}
  .contact-grid{grid-template-columns:1fr}
}
@media (max-width:640px){
  .nav{position:fixed;inset:68px 0 auto 0;flex-direction:column;background:#fff;border-bottom:1px solid var(--line);padding:14px 22px;gap:6px;transform:translateY(-120%);transition:transform .3s;box-shadow:var(--shadow)}
  .nav.open{transform:translateY(0)}
  .nav a{padding:10px 0;border-bottom:1px solid var(--line)}
  .nav-toggle{display:flex}
  .nav-toggle.open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
  .nav-toggle.open span:nth-child(2){opacity:0}
  .nav-toggle.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}
  .biz-grid,.adv-grid{grid-template-columns:1fr}
  .hero-stats{gap:24px}
  .section{padding:60px 0}
}