/* ============================================================
   CHANGLONG 外贸站全站样式 v1.0
   规范：工业深蓝+工程橙 / SVG图标(Font Awesome) / 禁用Emoji
   ============================================================ */
:root {
  --navy: #0f2a43; --navy-2: #16395c; --steel: #5b7186;
  --accent: #f59e0b; --accent-dark: #d97706;
  --bg: #ffffff; --bg-soft: #f4f7fa;
  --text: #1e293b; --muted: #64748b; --line: #e8edf2;
  --radius: 14px; --shadow: 0 10px 30px rgba(15,42,67,.10);
  --max: 1160px;
}
* { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; }
body { font-family:"Segoe UI","Helvetica Neue",Arial,"PingFang SC","Microsoft YaHei",sans-serif; color:var(--text); background:var(--bg); line-height:1.6; }
img { max-width:100%; display:block; }
a { text-decoration:none; color:inherit; }
.container { max-width:var(--max); margin:0 auto; padding:0 24px; }
section { padding:80px 0; }
.sec-head { text-align:center; max-width:660px; margin:0 auto 50px; }
.sec-head h2 { font-size:32px; color:var(--navy); margin-bottom:12px; }
.sec-head p { color:var(--muted); font-size:16px; }
.tagline { display:inline-block; background:rgba(245,158,11,.12); color:var(--accent-dark); font-weight:700; font-size:13px; letter-spacing:1.5px; text-transform:uppercase; padding:6px 16px; border-radius:999px; margin-bottom:18px; }

/* ---------- 按钮 ---------- */
.btn { display:inline-block; padding:13px 30px; border-radius:999px; font-weight:700; font-size:15px; transition:all .2s; cursor:pointer; border:none; }
.btn-primary { background:var(--accent); color:#fff; box-shadow:0 6px 18px rgba(245,158,11,.35); }
.btn-primary:hover { background:var(--accent-dark); transform:translateY(-2px); }
.btn-ghost { background:transparent; color:#fff; border:2px solid rgba(255,255,255,.55); }
.btn-ghost:hover { border-color:#fff; background:rgba(255,255,255,.08); }
.btn-outline { background:transparent; color:var(--navy); border:2px solid var(--navy); }
.btn-outline:hover { background:var(--navy); color:#fff; }
.btn-sm { padding:9px 20px; font-size:13px; }

/* ---------- 顶栏（两行布局） ---------- */
.topbar { background:var(--navy); color:#c6d4e2; font-size:13px; }
.topbar .container { display:flex; justify-content:space-between; align-items:center; height:40px; }
.topbar .brand { display:flex; align-items:center; gap:10px; color:#fff; font-weight:800; letter-spacing:1px; font-size:16px; }
.topbar .brand i { color:var(--accent); }
.topbar .brand small { color:#8fa3b5; font-weight:500; letter-spacing:0; }
.topbar .contact-links { display:flex; gap:20px; align-items:center; }
.topbar .contact-links a { color:#c6d4e2; }
.topbar .contact-links a:hover { color:var(--accent); }
.topbar .contact-links i { color:var(--accent); margin-right:6px; }

/* ---------- 主导航 ---------- */
header.site { position:sticky; top:0; z-index:100; background:rgba(255,255,255,.96); backdrop-filter:blur(10px); border-bottom:1px solid var(--line); box-shadow:0 2px 12px rgba(15,42,67,.06); }
.nav-row { display:flex; align-items:center; justify-content:space-between; height:64px; }
.mainnav { display:flex; align-items:center; gap:6px; }
.mainnav > ul { display:flex; list-style:none; gap:4px; }
.mainnav > ul > li { position:relative; }
.mainnav > ul > li > a { display:block; padding:10px 16px; font-weight:600; font-size:15px; color:var(--navy-2); border-radius:8px; }
.mainnav > ul > li > a:hover { color:var(--accent-dark); background:var(--bg-soft); }
.mainnav > ul > li > a i { font-size:11px; margin-left:4px; opacity:.6; }
/* 下拉菜单 */
.subnav { position:absolute; top:100%; left:0; min-width:250px; background:#fff; border:1px solid var(--line); border-radius:12px; box-shadow:var(--shadow); list-style:none; padding:8px; opacity:0; visibility:hidden; transform:translateY(8px); transition:all .2s; }
.mainnav li:hover > .subnav, .mainnav li:focus-within > .subnav { opacity:1; visibility:visible; transform:translateY(0); }
.subnav a { display:flex; align-items:center; gap:10px; padding:10px 14px; border-radius:8px; font-size:14px; color:var(--text); }
.subnav a:hover { background:var(--bg-soft); color:var(--accent-dark); }
.subnav i { color:var(--accent-dark); width:18px; text-align:center; }
/* 移动端汉堡 */
#menu-toggle { display:none; }
.burger { display:none; font-size:22px; color:var(--navy); cursor:pointer; }

/* ---------- WhatsApp 悬浮按钮 ---------- */
.wa-float { position:fixed; right:22px; bottom:22px; z-index:200; width:58px; height:58px; border-radius:50%; background:#25d366; color:#fff; display:flex; align-items:center; justify-content:center; font-size:30px; box-shadow:0 8px 24px rgba(37,211,102,.4); transition:transform .2s; }
.wa-float:hover { transform:scale(1.08); }

/* ---------- Hero ---------- */
.hero { background:linear-gradient(135deg,var(--navy) 0%,var(--navy-2) 55%,#1d4a75 100%); color:#fff; padding:100px 0 110px; position:relative; overflow:hidden; }
.hero::after { content:""; position:absolute; right:-140px; top:-140px; width:480px; height:480px; border-radius:50%; background:radial-gradient(circle,rgba(245,158,11,.25),transparent 65%); }
.hero .container { position:relative; z-index:1; max-width:820px; text-align:center; }
.hero h1 { font-size:44px; line-height:1.2; margin-bottom:20px; }
.hero h1 span { color:var(--accent); }
.hero p { font-size:17px; color:#c6d4e2; margin-bottom:34px; }
.hero-btns { display:flex; gap:16px; justify-content:center; flex-wrap:wrap; }

/* ---------- 内页横幅 ---------- */
.page-hero { background:linear-gradient(135deg,var(--navy),#1d4a75); color:#fff; padding:64px 0; text-align:center; }
.page-hero h1 { font-size:36px; margin-bottom:10px; }
.page-hero p { color:#c6d4e2; max-width:700px; margin:0 auto; }
.breadcrumb { font-size:13px; color:#8fa3b5; margin-top:12px; }
.breadcrumb a { color:#c6d4e2; }
.breadcrumb a:hover { color:var(--accent); }

/* ---------- 数据条 ---------- */
.stats { background:var(--bg-soft); padding:40px 0; }
.stats-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:20px; text-align:center; }
.stat b { font-size:34px; color:var(--navy); display:block; }
.stat span { color:var(--muted); font-size:14px; }

/* ---------- 网格与卡片 ---------- */
.grid { display:grid; grid-template-columns:repeat(3,1fr); gap:26px; }
.grid-4 { display:grid; grid-template-columns:repeat(4,1fr); gap:26px; }
.grid-2 { display:grid; grid-template-columns:repeat(2,1fr); gap:26px; }
.card { background:#fff; border:1px solid var(--line); border-radius:var(--radius); overflow:hidden; transition:all .25s; }
.card:hover { transform:translateY(-6px); box-shadow:var(--shadow); border-color:transparent; }
.card-img { height:170px; display:flex; align-items:center; justify-content:center; font-size:52px; color:#fff; background:linear-gradient(135deg,var(--navy-2),var(--steel)); padding:0; overflow:hidden; }
.card-img img { width:100%; height:100%; object-fit:cover; display:block; transition:transform .35s; }
.card:hover .card-img img { transform:scale(1.05); }
.card-img i { font-size:48px; }
.card-img.alt { background:linear-gradient(135deg,#1d4a75,#4a7aa5); }
.card-body { padding:22px 24px 26px; }
.card-body h3 { color:var(--navy); font-size:18px; margin-bottom:8px; }
.card-body p { color:var(--muted); font-size:14px; margin-bottom:14px; }
.card-body a.more { color:var(--accent-dark); font-weight:700; font-size:14px; }
.card-body a.more:hover { text-decoration:underline; }

/* ---------- Feature ---------- */
.feat { background:#fff; border-radius:var(--radius); padding:30px 28px; border:1px solid var(--line); }
.feat-icon { width:52px; height:52px; border-radius:12px; background:rgba(245,158,11,.14); display:flex; align-items:center; justify-content:center; font-size:22px; color:var(--accent-dark); margin-bottom:18px; }
.feat h3 { color:var(--navy); font-size:17px; margin-bottom:8px; }
.feat p { color:var(--muted); font-size:14px; }

/* ---------- FAQ ---------- */
.faq-list { max-width:780px; margin:0 auto; }
details { background:#fff; border:1px solid var(--line); border-radius:12px; margin-bottom:14px; overflow:hidden; }
summary { cursor:pointer; font-weight:700; color:var(--navy); padding:18px 22px; font-size:15px; list-style:none; position:relative; padding-right:48px; }
summary::-webkit-details-marker { display:none; }
summary::after { content:"+"; position:absolute; right:20px; top:50%; transform:translateY(-50%); font-size:22px; color:var(--accent-dark); transition:transform .2s; }
details[open] summary::after { transform:translateY(-50%) rotate(45deg); }
details .ans { padding:0 22px 18px; color:var(--muted); font-size:14px; }

/* ---------- 表格（规格/对比） ---------- */
.tbl { width:100%; border-collapse:collapse; font-size:14px; margin:18px 0; }
.tbl th { background:var(--navy); color:#fff; padding:11px 14px; text-align:left; }
.tbl td { border:1px solid var(--line); padding:10px 14px; }
.tbl tr:nth-child(even) td { background:var(--bg-soft); }

/* ---------- 清单 ---------- */
.check-list { list-style:none; }
.check-list li { padding-left:30px; position:relative; margin-bottom:10px; color:var(--text); font-size:15px; }
.check-list li::before { content:"\f00c"; font-family:"Font Awesome 6 Free"; font-weight:900; position:absolute; left:0; color:var(--accent-dark); }

/* ---------- 步骤流程 ---------- */
.steps { display:grid; grid-template-columns:repeat(3,1fr); gap:20px; counter-reset:step; }
.step { background:#fff; border:1px solid var(--line); border-radius:var(--radius); padding:24px; position:relative; }
.step::before { counter-increment:step; content:counter(step); position:absolute; top:-16px; left:22px; width:34px; height:34px; border-radius:50%; background:var(--accent); color:#fff; font-weight:800; display:flex; align-items:center; justify-content:center; }
.step h3 { color:var(--navy); font-size:16px; margin:10px 0 8px; }
.step p { color:var(--muted); font-size:14px; }

/* ---------- 文章页 ---------- */
.article { max-width:780px; margin:0 auto; font-size:16px; }
.article h2 { font-size:24px; color:var(--navy); margin:36px 0 14px; }
.article h3 { font-size:18px; color:var(--navy-2); margin:26px 0 10px; }
.article p { margin-bottom:16px; color:var(--text); }
.article ul { margin:0 0 16px 22px; }
.article li { margin-bottom:8px; }

/* ---------- 询盘表单 ---------- */
.cta { background:linear-gradient(135deg,var(--navy),#1d4a75); color:#fff; }
.cta-wrap { display:grid; grid-template-columns:1fr 1fr; gap:60px; align-items:center; }
.cta h2 { font-size:32px; margin-bottom:16px; }
.cta h2 span { color:var(--accent); }
.cta p { color:#c6d4e2; margin-bottom:24px; }
.contact-list { list-style:none; font-size:15px; color:#dbe6f0; }
.contact-list li { margin-bottom:12px; }
.contact-list i { color:var(--accent); width:22px; }
.contact-list a:hover { color:var(--accent); }
.form-box { background:#fff; border-radius:var(--radius); padding:34px; box-shadow:var(--shadow); color:var(--text); }
.form-box h3 { color:var(--navy); margin-bottom:6px; }
.form-box .hint { color:var(--muted); font-size:13px; margin-bottom:20px; }
.form-box label { display:block; font-size:13px; font-weight:700; color:var(--navy-2); margin:14px 0 6px; }
.form-box input, .form-box textarea, .form-box select { width:100%; padding:12px 14px; border:1.5px solid #d9e2ec; border-radius:9px; font-size:14px; font-family:inherit; outline:none; transition:border .2s; }
.form-box input:focus, .form-box textarea:focus { border-color:var(--accent); }
.form-box button { width:100%; margin-top:22px; }
.form-2col { display:grid; grid-template-columns:1fr 1fr; gap:0 16px; }

/* ---------- 产品详情页 (PDP) ---------- */
.pdp { display:grid; grid-template-columns:1.05fr 1fr; gap:44px; align-items:start; }
.pdp-main-img { width:100%; border-radius:var(--radius); border:1px solid var(--line); aspect-ratio:4/3; object-fit:contain; background:#fff; }
.pdp-thumbs { display:grid; grid-template-columns:repeat(5,1fr); gap:10px; margin-top:12px; }
.pdp-thumbs img { width:100%; aspect-ratio:4/3; object-fit:cover; border-radius:8px; border:2px solid var(--line); cursor:pointer; transition:border .15s; }
.pdp-thumbs img:hover, .pdp-thumbs img.on { border-color:var(--accent); }
.pdp h1 { font-size:26px; color:var(--navy); line-height:1.3; margin-bottom:8px; }
.pdp .sub { color:var(--muted); font-size:14px; margin-bottom:16px; }
.pdp-keyfacts { display:grid; grid-template-columns:repeat(3,1fr); gap:12px; margin:18px 0; }
.pdp-keyfacts div { background:var(--bg-soft); border-radius:10px; padding:12px 14px; text-align:center; }
.pdp-keyfacts b { display:block; color:var(--navy); font-size:15px; }
.pdp-keyfacts span { color:var(--muted); font-size:12px; }
.pdp-btns { display:flex; gap:12px; flex-wrap:wrap; margin-top:20px; }
.pdp-btns .btn-wa { background:#25d366; color:#fff; }
.pdp-btns .btn-wa:hover { background:#1da851; }
.pdp-sec { margin:56px 0 0; }
.pdp-sec h2 { font-size:24px; color:var(--navy); margin-bottom:16px; padding-left:12px; border-left:4px solid var(--accent); }
.badge-row { display:flex; gap:12px; flex-wrap:wrap; }
.badge-row span { background:var(--bg-soft); border:1px solid var(--line); border-radius:999px; padding:8px 18px; font-size:13px; color:var(--navy-2); font-weight:600; }
.badge-row span i { color:var(--accent-dark); margin-right:6px; }

/* ---------- 体验组件：返回顶部 / 灯箱 / 滚动淡入 ---------- */
.to-top { position:fixed; right:22px; bottom:92px; z-index:190; width:44px; height:44px; border-radius:50%; background:var(--navy); color:#fff; border:none; cursor:pointer; font-size:16px; box-shadow:0 6px 18px rgba(15,42,67,.3); opacity:0; visibility:hidden; transition:all .25s; }
.to-top.show { opacity:1; visibility:visible; }
.to-top:hover { background:var(--accent-dark); }
.lightbox { position:fixed; inset:0; z-index:300; background:rgba(10,25,40,.92); display:none; align-items:center; justify-content:center; cursor:zoom-out; }
.lightbox.open { display:flex; }
.lightbox img { max-width:92%; max-height:90%; border-radius:8px; box-shadow:0 20px 60px rgba(0,0,0,.5); }
.reveal { opacity:0; transform:translateY(22px); transition:opacity .6s ease, transform .6s ease; }
.reveal.in { opacity:1; transform:none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity:1; transform:none; transition:none; } }

/* ---------- 案例区组件 ---------- */
.pill { display:inline-block; background:var(--bg-soft); border:1px solid var(--line); border-radius:999px; padding:3px 12px; font-size:12px; font-weight:600; color:var(--navy-2); margin-right:6px; }
.pill i { color:var(--accent-dark); margin-right:4px; }
.metric { color:var(--accent-dark); font-weight:700; font-size:14px; }
.metric i { margin-right:6px; }
.filter-chips { display:flex; gap:10px; justify-content:center; flex-wrap:wrap; margin-bottom:34px; }
.chip { background:#fff; border:1.5px solid var(--line); border-radius:999px; padding:8px 22px; font-size:14px; font-weight:600; color:var(--navy-2); cursor:pointer; transition:all .15s; }
.chip:hover { border-color:var(--accent); color:var(--accent-dark); }
.chip.on { background:var(--navy); border-color:var(--navy); color:#fff; }
.case-grid-hide { display:none !important; }

/* ---------- Hero 轮播 ---------- */
.hero-slides { position:absolute; inset:0; }
.hero-slides img { position:absolute; inset:0; width:100%; height:100%; object-fit:cover; opacity:0; animation:heroFade 15s infinite; }
.hero-slides img:nth-child(2) { animation-delay:5s; }
.hero-slides img:nth-child(3) { animation-delay:10s; }
@keyframes heroFade { 0%{opacity:0} 5%{opacity:1} 30%{opacity:1} 38%{opacity:0} 100%{opacity:0} }
.hero-dim { position:absolute; inset:0; background:linear-gradient(135deg, rgba(15,42,67,.90), rgba(22,57,92,.84)); }

/* ---------- WhatsApp 气泡提示 ---------- */
.wa-bubble { position:absolute; right:70px; top:50%; transform:translateY(-50%); background:var(--navy); color:#fff; font-size:13px; font-weight:600; padding:9px 16px; border-radius:10px; white-space:nowrap; opacity:0; visibility:hidden; transition:all .3s; box-shadow:var(--shadow); }
.wa-bubble::after { content:""; position:absolute; right:-6px; top:50%; transform:translateY(-50%); border:6px solid transparent; border-left-color:var(--navy); }
.wa-float:hover .wa-bubble, .wa-bubble.show { opacity:1; visibility:visible; }

/* ---------- PDP 标签页 ---------- */
.pdp-tabbar { display:flex; gap:8px; flex-wrap:wrap; margin:52px 0 22px; border-bottom:2px solid var(--line); padding-bottom:0; }
.pdp-tabbar button { background:none; border:none; border-bottom:3px solid transparent; padding:12px 20px; font-size:15px; font-weight:700; color:var(--muted); cursor:pointer; transition:all .15s; font-family:inherit; }
.pdp-tabbar button:hover { color:var(--navy); }
.pdp-tabbar button.on { color:var(--navy); border-bottom-color:var(--accent); }
.tabpane { display:none; }
.tabpane.on { display:block; animation:paneIn .3s ease; }
@keyframes paneIn { from{opacity:0; transform:translateY(8px)} to{opacity:1; transform:none} }

/* ---------- 页脚 ---------- */
footer.site { background:#0b1f33; color:#8fa3b5; padding:56px 0 0; font-size:14px; }
.foot-grid { display:grid; grid-template-columns:2fr 1fr 1fr 1.4fr; gap:40px; padding-bottom:40px; }
.foot-grid h4 { color:#fff; font-size:15px; margin-bottom:16px; }
.foot-grid ul { list-style:none; }
.foot-grid li { margin-bottom:9px; }
.foot-grid a:hover { color:var(--accent); }
.foot-grid .socials { display:flex; gap:12px; margin-top:14px; }
.foot-grid .socials a { width:36px; height:36px; border-radius:8px; background:rgba(255,255,255,.08); display:flex; align-items:center; justify-content:center; color:#c6d4e2; }
.foot-grid .socials a:hover { background:var(--accent); color:#fff; }
.foot-bottom { border-top:1px solid rgba(255,255,255,.08); padding:18px 0; text-align:center; font-size:13px; }

/* ---------- 占位提示 ---------- */
.todo-note { background:#fffbeb; border:1px dashed var(--accent); border-radius:10px; padding:12px 16px; font-size:13px; color:#92400e; margin:14px 0; }

/* ---------- 响应式 ---------- */
@media (max-width:920px) {
  .grid, .feat-grid { grid-template-columns:repeat(2,1fr); }
  .grid-4, .steps { grid-template-columns:repeat(2,1fr); }
  .stats-grid { grid-template-columns:repeat(2,1fr); }
  .cta-wrap, .grid-2 { grid-template-columns:1fr; }
  .hero h1 { font-size:34px; }
  .foot-grid { grid-template-columns:1fr 1fr; }
  /* 移动端导航 */
  .burger { display:block; }
  .mainnav { display:none; position:absolute; top:64px; left:0; right:0; background:#fff; flex-direction:column; align-items:stretch; padding:14px 20px 20px; border-bottom:1px solid var(--line); box-shadow:var(--shadow); }
  .mainnav > ul { flex-direction:column; gap:2px; }
  .subnav { position:static; opacity:1; visibility:visible; transform:none; box-shadow:none; border:none; padding-left:18px; }
  #menu-toggle:checked ~ .mainnav { display:flex; }
  .topbar .contact-links span.hide-m { display:none; }
}
@media (max-width:560px) {
  .grid, .grid-4, .steps, .feat-grid { grid-template-columns:1fr; }
  section { padding:56px 0; }
  .hero { padding:72px 0; }
  .form-2col { grid-template-columns:1fr; }
}
.grid-3 { display:grid; grid-template-columns:repeat(3,1fr); gap:24px; }
@media (max-width:900px){ .grid-3{ grid-template-columns:repeat(2,1fr);} }
@media (max-width:640px){ .grid-3{ grid-template-columns:1fr;} }
.contact-person { display:flex; gap:14px; align-items:flex-start; background:#fceef2; border:1px solid #f6dde4; border-radius:14px; padding:16px 18px; margin-top:16px; }
.cp-avatar { width:52px; height:52px; border-radius:50%; background:var(--accent); color:#fff; font-size:22px; font-weight:700; display:flex; align-items:center; justify-content:center; flex:none; }
.cp-info b { display:block; color:var(--navy); font-size:16px; }
.cp-info span { display:block; color:var(--muted); font-size:13px; margin-bottom:6px; }
.cp-links { display:flex; flex-direction:column; gap:3px; }
.cp-links a { font-size:13px; color:var(--accent-dark); font-weight:600; }