/* ============ 基础变量（主题在 theme-x.css 中覆盖） ============ */
:root{
  --bg:#ffffff; --bg-alt:#f5f7fb; --surface:#ffffff;
  --text:#1d2433; --text-soft:#5b6678;
  --primary:#1f6feb; --primary-2:#0b4fc4; --accent:#16c79a;
  --border:#e7ecf3; --radius:16px; --shadow:0 10px 30px rgba(20,40,80,.08);
  --font:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
  --maxw:1180px; --header-h:66px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--font);color:var(--text);background:var(--bg);line-height:1.7;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ============ 顶部导航 ============ */
.site-header{position:sticky;top:0;z-index:50;height:var(--header-h);
  background:color-mix(in srgb,var(--bg) 88%, transparent);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--border)}
.nav-wrap{height:100%;display:flex;align-items:center;justify-content:space-between}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:19px}
.brand-logo{width:34px;height:34px;border-radius:9px;display:grid;place-items:center;color:#fff;
  background:linear-gradient(135deg,var(--primary),var(--primary-2));font-size:18px}
.nav-links{display:flex;gap:26px;font-size:15px}
.nav-links a{position:relative;padding:6px 0;color:var(--text-soft);transition:.2s}
.nav-links a:hover{color:var(--primary)}
.nav-links a::after{content:"";position:absolute;left:0;bottom:0;width:0;height:2px;background:var(--primary);transition:.25s}
.nav-links a:hover::after{width:100%}
.nav-toggle{display:none;background:none;border:0;font-size:24px;cursor:pointer;color:var(--text)}

/* ============ Hero ============ */
.hero{position:relative;height:88vh;min-height:520px;overflow:hidden}
.hero-slides{height:100%;position:relative}
.hero-slide{position:absolute;inset:0;opacity:0;transition:opacity .8s;background-size:cover;background-position:center;display:flex;align-items:center}
.hero-slide.active{opacity:1}
.hero-slide::before{content:"";position:absolute;inset:0;background:linear-gradient(120deg,rgba(8,20,45,.78),rgba(8,20,45,.35))}
.hero-inner{position:relative;z-index:2;color:#fff;max-width:760px;padding:0 20px;margin:0 auto;width:100%}
.hero-inner{max-width:var(--maxw)}
.hero-slide h1{font-size:clamp(28px,5vw,52px);line-height:1.2;margin-bottom:16px;font-weight:800}
.hero-slide p{font-size:clamp(15px,2vw,20px);opacity:.92;margin-bottom:26px}
.hero-cta{display:inline-block;background:var(--accent);color:#06281f;padding:13px 30px;border-radius:40px;font-weight:700;transition:.2s}
.hero-cta:hover{transform:translateY(-2px);box-shadow:0 12px 26px rgba(22,199,154,.4)}
.hero-dots{position:absolute;bottom:22px;left:50%;transform:translateX(-50%);z-index:3;display:flex;gap:10px}
.hero-dots button{width:11px;height:11px;border-radius:50%;border:0;background:rgba(255,255,255,.5);cursor:pointer}
.hero-dots button.active{background:#fff;width:26px;border-radius:6px}
.hero-scroll{position:absolute;bottom:18px;right:24px;z-index:3;color:#fff;font-size:30px;animation:bob 1.8s infinite}
@keyframes bob{0%,100%{transform:translateY(0)}50%{transform:translateY(8px)}}

/* ============ 区块通用 ============ */
.section{padding:78px 0}
.section-alt{background:var(--bg-alt)}
.sec-head{text-align:center;margin-bottom:46px;position:relative}
.sec-tag{display:inline-block;letter-spacing:3px;font-size:13px;color:var(--primary);font-weight:700;margin-bottom:8px}
.sec-title{font-size:clamp(24px,3.4vw,34px);font-weight:800;position:relative;display:inline-block}
.sec-title::after{content:"";display:block;width:46px;height:4px;border-radius:3px;background:var(--primary);margin:12px auto 0}
.sec-sub{color:var(--text-soft);margin-top:12px}
.sec-more{position:absolute;right:0;top:6px;color:var(--primary);font-weight:600;font-size:14px}

/* ============ 关于我们 ============ */
.about-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:40px;align-items:center}
.about-text p{color:var(--text-soft);font-size:16px;text-align:justify}
.about-stats{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}
.stat{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:22px;text-align:center;box-shadow:var(--shadow)}
.stat b{display:block;font-size:30px;color:var(--primary);font-weight:800}
.stat span{color:var(--text-soft);font-size:14px}

/* ============ 卡片网格（业务） ============ */
.card-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.s-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:28px;transition:.25s;box-shadow:var(--shadow)}
.s-card:hover{transform:translateY(-6px);border-color:var(--primary)}
.s-icon{width:52px;height:52px;border-radius:14px;display:grid;place-items:center;font-size:26px;margin-bottom:16px;
  background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff}
.s-card h3{font-size:19px;margin-bottom:8px}
.s-card p{color:var(--text-soft);font-size:14.5px}
.s-card .s-more{display:inline-block;margin-top:14px;color:var(--primary);font-size:14px;font-weight:600}

/* ============ 发展历程 ============ */
.timeline{position:relative;max-width:820px;margin:0 auto;padding-left:30px}
.timeline::before{content:"";position:absolute;left:8px;top:0;bottom:0;width:2px;background:var(--border)}
.tl-item{position:relative;padding:0 0 30px 26px}
.tl-item::before{content:"";position:absolute;left:-26px;top:4px;width:18px;height:18px;border-radius:50%;
  background:var(--primary);border:4px solid var(--bg);box-shadow:0 0 0 2px var(--primary)}
.tl-year{font-weight:800;color:var(--primary);font-size:17px}
.tl-item h4{font-size:17px;margin:4px 0}
.tl-item p{color:var(--text-soft);font-size:14.5px}

/* ============ 案例 ============ */
.case-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.case{background:var(--surface);border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);box-shadow:var(--shadow);transition:.25s}
.case:hover{transform:translateY(-5px)}
.case img{height:180px;width:100%;object-fit:cover}
.case-body{padding:18px}
.case-body h4{font-size:16px;margin-bottom:6px}
.case-body p{color:var(--text-soft);font-size:13.5px}

/* ============ 合作伙伴 ============ */
.partner-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px}
.partner{background:var(--surface);border:1px solid var(--border);border-radius:12px;height:80px;display:grid;place-items:center;
  font-weight:700;color:var(--text-soft);transition:.2s}
.partner:hover{color:var(--primary);border-color:var(--primary)}

/* ============ 新闻 ============ */
.news-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.news{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:.25s;display:flex;flex-direction:column}
.news:hover{transform:translateY(-5px)}
.news img{height:190px;width:100%;object-fit:cover}
.news-body{padding:18px;flex:1;display:flex;flex-direction:column}
.news-body .tag{font-size:12px;color:var(--primary);font-weight:700}
.news-body h4{font-size:17px;margin:6px 0 8px;line-height:1.4}
.news-body p{color:var(--text-soft);font-size:13.5px;flex:1;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.news-body .date{margin-top:10px;color:var(--text-soft);font-size:12.5px}

/* ============ 联系 ============ */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:46px;align-items:start}
.contact-lead{color:var(--text-soft);margin:14px 0 22px}
.contact-list{list-style:none;display:flex;flex-direction:column;gap:14px}
.contact-list li{display:flex;gap:12px;align-items:flex-start}
.contact-list .ic{width:38px;height:38px;border-radius:10px;background:var(--primary);color:#fff;display:grid;place-items:center;flex:none}
.contact-list b{display:block;font-size:14px;color:var(--text-soft);font-weight:600}
.contact-form{display:flex;flex-direction:column;gap:12px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.contact-form input,.contact-form textarea{border:1px solid var(--border);border-radius:10px;padding:12px 14px;font:inherit;background:var(--bg);color:var(--text)}
.contact-form input:focus,.contact-form textarea:focus{outline:none;border-color:var(--primary)}
.btn-primary{background:var(--primary);color:#fff;border:0;border-radius:10px;padding:12px 18px;font-weight:700;cursor:pointer;transition:.2s}
.btn-primary:hover{background:var(--primary-2)}

/* ============ 页脚 ============ */
.site-footer{background:color-mix(in srgb,var(--text) 92%, #000);color:#cfd6e4;padding:54px 0 0}
.footer-wrap{display:grid;grid-template-columns:1.6fr 1fr 1fr;gap:30px}
.site-footer .brand-name{color:#fff}
.footer-desc{color:#9aa6bb;font-size:14px;margin-top:14px;max-width:420px}
.site-footer h4{color:#fff;margin-bottom:14px;font-size:15px}
.footer-col a{display:block;color:#9aa6bb;font-size:14px;padding:4px 0}
.footer-col a:hover{color:var(--accent)}
.footer-bar{border-top:1px solid rgba(255,255,255,.08);margin-top:36px;padding:18px 20px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px;color:#8c97ad;font-size:13px}

/* ============ 主题预览切换器 ============ */
.theme-picker{position:fixed;right:18px;bottom:18px;z-index:60;background:var(--surface);border:1px solid var(--border);
  border-radius:40px;padding:8px 12px;display:flex;align-items:center;gap:8px;box-shadow:var(--shadow);font-size:13px}
.theme-picker span{color:var(--text-soft)}
.theme-picker button{width:30px;height:30px;border-radius:50%;border:2px solid var(--border);cursor:pointer;font-weight:700;background:#fff;color:var(--text)}
.theme-picker button.active{border-color:var(--primary);background:var(--primary);color:#fff}

/* ============ 响应式 ============ */
@media (max-width:980px){
  .card-grid,.case-grid,.news-grid{grid-template-columns:repeat(2,1fr)}
  .partner-grid{grid-template-columns:repeat(3,1fr)}
  .about-grid,.contact-grid{grid-template-columns:1fr}
}
@media (max-width:680px){
  .nav-links{position:absolute;top:var(--header-h);left:0;right:0;background:var(--bg);flex-direction:column;gap:0;
    padding:8px 0;border-bottom:1px solid var(--border);transform:translateY(-120%);transition:.3s;box-shadow:var(--shadow)}
  .nav-links.open{transform:translateY(0)}
  .nav-links a{padding:12px 20px}
  .nav-toggle{display:block}
  .sec-more{position:static;display:block;margin-top:10px}
  .card-grid,.case-grid,.news-grid,.partner-grid{grid-template-columns:1fr}
  .hero{height:70vh}
  .section{padding:54px 0}
}