/* =========================================================
   gnzk-website 前端样式 —— 复刻深蓝 + 能源绿科技风
   ========================================================= */
:root{
  --brand-dark:#0a2540;
  --brand:#0e4d92;
  --brand-light:#2a7fd4;
  --energy:#18c29c;
  --energy-dark:#0f9b7d;
  --energy-light:#d7f7ee;
  --slate-900:#0f172a;
  --slate-800:#1e293b;
  --slate-600:#475569;
  --slate-500:#64748b;
  --slate-400:#94a3b8;
  --bg-soft:#f6f9fc;
  --white:#fff;
  --radius:14px;
  --radius-lg:20px;
  --shadow:0 4px 20px rgba(10,37,64,.06);
  --shadow-hover:0 14px 34px rgba(10,37,64,.14);
  --maxw:1180px;
  --nav-h:68px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",Roboto,Helvetica,Arial,sans-serif;
  color:var(--slate-800);
  background:var(--white);
  line-height:1.65;
  -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 20px}
h1,h2,h3,h4{line-height:1.25;color:var(--slate-900);font-weight:700}
.section{padding:72px 0}
.section-head{text-align:center;max-width:640px;margin:0 auto 40px}
.section-head h2{font-size:30px}
.section-head p{margin-top:10px;color:var(--slate-500)}
.section-head .bar{width:48px;height:4px;border-radius:4px;background:var(--energy);margin:14px auto 0}

/* ---------- 按钮 ---------- */
.btn{display:inline-block;padding:12px 28px;border-radius:999px;font-weight:600;font-size:15px;transition:.2s;border:1px solid transparent;cursor:pointer}
.btn-energy{background:var(--energy);color:var(--brand-dark)}
.btn-energy:hover{background:var(--energy-dark);color:#fff}
.btn-ghost{border-color:rgba(255,255,255,.6);color:#fff}
.btn-ghost:hover{background:rgba(255,255,255,.12)}
.btn-brand{background:var(--brand);color:#fff}
.btn-brand:hover{background:var(--brand-light)}

/* ---------- 顶部导航 ---------- */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);backdrop-filter:blur(8px);border-bottom:1px solid #eef2f7}
.nav-wrap{display:flex;align-items:center;justify-content:space-between;height:var(--nav-h)}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:20px;color:var(--brand-dark)}
.brand img{height:34px;width:auto;border-radius:8px}
.brand-name{letter-spacing:.04em}
.nav ul{display:flex;align-items:center;gap:6px;list-style:none}
.nav a{padding:8px 14px;border-radius:8px;font-size:15px;color:var(--slate-600);transition:.2s}
.nav a:hover{color:var(--brand)}
.nav li.active a{color:var(--brand);font-weight:600}
.nav-cta{background:var(--energy);color:var(--brand-dark)!important;font-weight:600}
.nav-cta:hover{background:var(--energy-dark);color:#fff!important}
.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(--slate-800);border-radius:2px;transition:.2s}

/* ---------- Hero ---------- */
.hero{position:relative;overflow:hidden;color:#fff;background:linear-gradient(135deg,var(--brand-dark),var(--brand) 55%,var(--brand-light))}
.hero::before{content:"";position:absolute;right:-120px;top:-140px;width:460px;height:460px;border-radius:50%;border:26px solid rgba(24,194,156,.18)}
.hero::after{content:"";position:absolute;left:-100px;bottom:-150px;width:380px;height:380px;border-radius:50%;border:22px solid rgba(255,255,255,.08)}
.hero-inner{position:relative;z-index:1;text-align:center;padding:120px 0 110px}
.hero .eyebrow{letter-spacing:.3em;font-weight:600;color:var(--energy);font-size:14px;text-transform:uppercase}
.hero h1{font-size:clamp(30px,5vw,52px);margin:14px 0 16px;color:#fff}
.hero .lead{font-size:clamp(18px,2.4vw,26px);font-weight:600;color:var(--energy)}
.hero .sub{max-width:680px;margin:18px auto 0;color:rgba(219,234,254,.9);font-size:16px}
.hero-actions{margin-top:36px;display:flex;gap:16px;justify-content:center;flex-wrap:wrap}

/* ---------- 数据条 ---------- */
.stats{background:var(--brand-dark);color:#fff}
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;padding:48px 0;text-align:center}
.stat .num{font-size:clamp(28px,4vw,42px);font-weight:800;color:var(--energy)}
.stat .lbl{margin-top:6px;font-size:13px;color:rgba(219,234,254,.7)}

/* ---------- 卡片网格 ---------- */
.grid{display:grid;gap:22px}
.grid-4{grid-template-columns:repeat(4,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.card{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden;transition:.25s;border:1px solid #eef2f7}
.card:hover{transform:translateY(-6px);box-shadow:var(--shadow-hover)}
.card .thumb{height:180px;overflow:hidden;background:linear-gradient(135deg,#eaf2fb,#dff5ef)}
.card .thumb img{width:100%;height:100%;object-fit:cover;transition:.3s}
.card:hover .thumb img{transform:scale(1.05)}
.card .body{padding:22px}
.card .body h3{font-size:18px}
.card .body p{margin-top:8px;color:var(--slate-500);font-size:14px}
.card .more{display:inline-block;margin-top:12px;font-size:13px;font-weight:600;color:var(--brand);opacity:0;transition:.2s}
.card:hover .more{opacity:1}

/* ---------- 优势 ---------- */
.feature{background:var(--bg-soft)}
.feature-card{border-top:4px solid var(--energy);background:#fff;border-radius:var(--radius);padding:32px;box-shadow:var(--shadow)}
.feature-card .idx{font-size:40px;font-weight:800;color:#eef2f7}
.feature-card h3{margin:8px 0;color:var(--brand)}
.feature-card p{color:var(--slate-500);font-size:14px}

/* ---------- 新闻 ---------- */
.news-card .body{padding:22px}
.news-card .tag{display:inline-block;background:var(--energy-light);color:var(--energy-dark);font-size:12px;font-weight:600;padding:2px 10px;border-radius:999px}
.news-card .date{color:var(--slate-400);font-size:13px;margin-left:10px}
.news-card .src{display:block;margin-top:8px;color:var(--energy-dark);font-size:12px;font-weight:600}
.article-source{margin-top:24px;padding:14px 16px;background:#f4f7fb;border-radius:var(--radius);font-size:14px;color:var(--slate-900)}
.article-source a{color:var(--brand);font-weight:600}
.news-card h3{font-size:17px;margin-top:10px}
.news-card p{color:var(--slate-500);font-size:14px;margin-top:8px}

/* ---------- CTA ---------- */
.cta{background:linear-gradient(90deg,var(--brand-dark),var(--brand));color:#fff;text-align:center;padding:64px 0}
.cta h2{color:#fff;font-size:28px}
.cta p{color:rgba(219,234,254,.85);margin:12px 0 28px}

/* ---------- 面包屑 / 详情 ---------- */
.page-hero{background:linear-gradient(135deg,var(--brand-dark),var(--brand));color:#fff;padding:64px 0}
.page-hero h1{color:#fff;font-size:34px}
.page-hero p{color:rgba(219,234,254,.85);margin-top:10px}
.breadcrumb{padding:16px 0;color:var(--slate-400);font-size:14px}
.breadcrumb a{color:var(--slate-500)}
.prod-detail{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:start}
.prod-detail .cover{border-radius:var(--radius-lg);overflow:hidden;box-shadow:var(--shadow)}
.spec-list{list-style:none;margin-top:20px}
.spec-list li{display:flex;justify-content:space-between;padding:12px 0;border-bottom:1px dashed #e2e8f0;font-size:15px}
.spec-list li span:first-child{color:var(--slate-500)}
.spec-list li span:last-child{font-weight:600;color:var(--slate-800)}
.prose{max-width:760px}
.prose h2{font-size:22px;margin:28px 0 12px}
.prose p{margin-bottom:14px;color:var(--slate-600);font-size:16px}

/* ---------- 联系 / 表单 ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px}
.info-list{list-style:none}
.info-list li{padding:14px 0;border-bottom:1px solid #eef2f7;color:var(--slate-600)}
.form{background:#fff;border-radius:var(--radius);padding:30px;box-shadow:var(--shadow)}
.form label{display:block;font-size:14px;font-weight:600;margin:14px 0 6px;color:var(--slate-700)}
.form input,.form textarea,.form select{
  width:100%;padding:11px 14px;border:1px solid #dbe3ec;border-radius:10px;font-size:15px;font-family:inherit;transition:.2s;background:#fff;
}
.form input:focus,.form textarea:focus,.form select:focus{outline:none;border-color:var(--brand-light);box-shadow:0 0 0 3px rgba(42,127,212,.12)}
.form textarea{resize:vertical;min-height:110px}
.form .err{color:#dc2626;font-size:13px;margin-top:4px}
.form .ok{color:var(--energy-dark);font-size:14px;margin-top:10px;font-weight:600}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:14px}

/* ---------- 页脚 ---------- */
.site-footer{background:var(--brand-dark);color:#cbd5e1;padding:56px 0 0}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.2fr;gap:30px}
.footer-brand{font-size:22px;font-weight:800;color:#fff}
.footer-slogan{color:#94a3b8;font-size:14px;margin-top:10px;max-width:280px}
.site-footer h4{color:#fff;font-size:15px;margin-bottom:14px}
.site-footer ul{list-style:none}
.site-footer li{margin-bottom:8px;font-size:14px}
.site-footer a:hover{color:var(--energy)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);margin-top:40px;padding:18px 0;text-align:center;font-size:13px;color:#64748b;display:flex;gap:14px;justify-content:center;flex-wrap:wrap}

/* ---------- 响应式 ---------- */
@media (max-width:980px){
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .grid-3{grid-template-columns:repeat(2,1fr)}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
  .prod-detail,.contact-grid{grid-template-columns:1fr}
}
@media (max-width:680px){
  .nav{position:absolute;top:var(--nav-h);left:0;right:0;background:#fff;flex-direction:column;padding:10px 20px;box-shadow:var(--shadow);display:none}
  .nav.open{display:block}
  .nav ul{flex-direction:column;align-items:stretch;gap:2px}
  .nav a{display:block;padding:12px 10px}
  .nav-cta{text-align:center;margin-top:8px}
  .nav-toggle{display:flex}
  .grid-4,.grid-3,.grid-2{grid-template-columns:1fr}
  .form-row{grid-template-columns:1fr}
  .section{padding:52px 0}
}