/* ============================================
   科索照明官网 1:1 还原（基于凡科原站）
   主色：#1C52AC 企业蓝，辅 #26A59A
   ============================================ */

:root {
  --primary: #1c52ac;
  --primary-dark: #14407f;
  --secondary: #26a59a;
  --text: #333;
  --text-mute: #888;
  --bg: #fff;
  --bg-soft: #f7f9fc;
  --border: #dedede;
  --maxw: 1200px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: "Microsoft YaHei", "微软雅黑", "PingFang SC", "Hiragino Sans GB", sans-serif;
  color: var(--text);
  font-size: 14px;
  line-height: 1.7;
  background: var(--bg);
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ============ 顶部导航 ============ */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: 80px; background: rgba(255,255,255,0.97);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center;
}
.header .wrap { display: flex; align-items: center; justify-content: space-between; height: 100%; }
.logo { display: flex; align-items: center; gap: 10px; }
.logo img { height: 56px; }
.nav { display: flex; gap: 4px; }
.nav a {
  padding: 10px 22px; font-size: 16px; color: #555; position: relative;
  transition: color .2s;
}
.nav a:hover, .nav a.active { color: var(--primary); }
.nav a.active::after {
  content: ""; position: absolute; left: 22px; right: 22px; bottom: -28px;
  height: 3px; background: var(--primary);
}
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 24px; height: 2px; background: #333; margin: 4px 0; transition: .2s; }

/* ============ Hero 视频 ============ */
.hero {
  position: relative; height: 100vh; min-height: 560px; max-height: 760px;
  margin-top: 80px; overflow: hidden;
  background: #0b1320;
}
.hero video {
  position: absolute; inset: 0; width: 100%; height: 100%;
  object-fit: cover; z-index: 0;
}
.hero::after {
  content: ""; position: absolute; inset: 0; z-index: 1;
  background: linear-gradient(to bottom, rgba(0,0,0,.25) 0%, rgba(0,0,0,.55) 100%);
}
.hero-content {
  position: relative; z-index: 2; color: #fff; text-align: center;
  height: 100%; display: flex; flex-direction: column; justify-content: flex-end;
  padding-bottom: 90px;
}
.hero-content h1 { font-size: 48px; font-weight: 700; margin: 0 0 18px; letter-spacing: 4px; text-shadow: 0 4px 16px rgba(0,0,0,.5); }
.hero-content p { font-size: 18px; letter-spacing: 8px; margin: 0; opacity: .9; }

/* ============ 通用 Section ============ */
.section { padding: 80px 0; }
.section-title { text-align: center; margin-bottom: 60px; }
.section-title h2 { font-size: 32px; color: var(--primary); margin: 0 0 12px; letter-spacing: 2px; }
.section-title .en { font-size: 14px; color: var(--text-mute); letter-spacing: 4px; }
.section-title::after {
  content: ""; display: block; width: 50px; height: 2px; background: var(--secondary);
  margin: 18px auto 0;
}

/* ============ 品牌介绍 ============ */
.intro { background: var(--bg-soft); }
.intro-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.intro-text p { font-size: 16px; line-height: 2; color: #444; text-align: justify; }
.intro-img img { border-radius: 6px; box-shadow: 0 8px 32px rgba(28,82,172,.12); }

/* ============ 发展历程时间线 ============ */
.timeline { position: relative; max-width: 980px; margin: 0 auto; padding: 40px 0; }
.timeline::before {
  content: ""; position: absolute; left: 50%; top: 0; bottom: 0; width: 2px;
  background: linear-gradient(to bottom, transparent, var(--primary) 12%, var(--primary) 88%, transparent);
  transform: translateX(-50%);
}
.tl-item { display: flex; align-items: center; gap: 40px; margin-bottom: 60px; }
.tl-item:nth-child(odd) { flex-direction: row; }
.tl-item:nth-child(even) { flex-direction: row-reverse; }
.tl-year {
  flex: 0 0 50%; text-align: right; padding-right: 40px;
}
.tl-item:nth-child(even) .tl-year { text-align: left; padding-right: 0; padding-left: 40px; }
.tl-year .y { font-size: 38px; color: var(--primary); font-weight: 700; line-height: 1; letter-spacing: 2px; }
.tl-year .e { font-size: 12px; color: var(--text-mute); letter-spacing: 3px; }
.tl-card {
  flex: 0 0 50%; background: #fff; border: 1px solid var(--border);
  border-radius: 8px; padding: 24px 28px; box-shadow: 0 6px 20px rgba(0,0,0,.06);
  position: relative;
}
.tl-card::before {
  content: ""; position: absolute; top: 32px; width: 14px; height: 14px;
  background: var(--primary); border-radius: 50%; border: 3px solid #fff;
  box-shadow: 0 0 0 2px var(--primary);
}
.tl-item:nth-child(odd) .tl-card::before { left: -50px; }
.tl-item:nth-child(even) .tl-card::before { right: -50px; }
.tl-card h4 { margin: 0 0 8px; font-size: 18px; color: var(--primary); }
.tl-card p { margin: 0; color: #666; }
.tl-card .icon {
  position: absolute; top: -22px; right: 20px; width: 44px; height: 44px;
  border-radius: 50%; background: var(--secondary); display: flex; align-items: center; justify-content: center;
}
.tl-card .icon img { width: 22px; height: 22px; filter: brightness(0) invert(1); }

/* ============ 服务理念 ============ */
.service { background: #fff; }
.svc-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; }
.svc-item { text-align: center; padding: 40px 24px; border-radius: 8px; transition: .25s; }
.svc-item:hover { transform: translateY(-6px); box-shadow: 0 16px 40px rgba(28,82,172,.12); }
.svc-item img { width: 180px; height: 180px; margin: 0 auto 24px; border-radius: 50%; object-fit: cover; }
.svc-item h3 { font-size: 22px; color: var(--primary); margin: 0 0 12px; letter-spacing: 2px; }
.svc-item p { color: #666; margin: 0; }

/* ============ 产品视频网格 ============ */
.video-section { padding: 70px 0; }
.vgroup { margin-bottom: 70px; }
.vgroup-title { text-align: center; margin-bottom: 40px; }
.vgroup-title h3 { font-size: 28px; color: var(--primary); margin: 0; letter-spacing: 6px; position: relative; display: inline-block; }
.vgroup-title h3::before, .vgroup-title h3::after {
  content: ""; position: absolute; top: 50%; width: 60px; height: 2px; background: var(--secondary);
}
.vgroup-title h3::before { right: 100%; margin-right: 24px; }
.vgroup-title h3::after { left: 100%; margin-left: 24px; }
.vgroup-title .en { font-size: 13px; color: var(--text-mute); letter-spacing: 4px; margin-top: 8px; }
.vgrid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.vgrid-3 { grid-template-columns: repeat(3, 1fr); }
.vgrid-5 { grid-template-columns: repeat(5, 1fr); }
.vcard { background: #fff; border-radius: 8px; overflow: hidden; box-shadow: 0 4px 16px rgba(0,0,0,.06); transition: .25s; }
.vcard:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(28,82,172,.14); }
.vbox { position: relative; aspect-ratio: 16/10; background: #0b1320; overflow: hidden; }
.vbox video { width: 100%; height: 100%; object-fit: cover; cursor: pointer; display: block; }
.vname { padding: 14px 16px; text-align: center; font-size: 15px; color: #333; }

/* ============ 案例网格 ============ */
.case-tabs { display: flex; justify-content: center; gap: 10px; margin-bottom: 50px; flex-wrap: wrap; }
.case-tab { padding: 10px 30px; border: 1px solid var(--primary); color: var(--primary); background: #fff; cursor: pointer; border-radius: 4px; font-size: 16px; transition: .2s; }
.case-tab.active, .case-tab:hover { background: var(--primary); color: #fff; }
.case-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.case-card { position: relative; border-radius: 8px; overflow: hidden; aspect-ratio: 1; cursor: pointer; box-shadow: 0 4px 16px rgba(0,0,0,.08); transition: .3s; }
.case-card img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s; }
.case-card:hover { transform: translateY(-4px); }
.case-card:hover img { transform: scale(1.08); }
.case-card::after {
  content: ""; position: absolute; inset: 0; background: linear-gradient(to top, rgba(0,0,0,.65) 0%, transparent 50%);
}
.case-name {
  position: absolute; bottom: 14px; left: 14px; right: 14px; z-index: 2; color: #fff;
  font-size: 14px; letter-spacing: 1px;
}
.case-cat-tag {
  position: absolute; top: 12px; right: 12px; z-index: 3;
  background: rgba(28,82,172,.85); color: #fff;
  padding: 4px 12px; font-size: 12px; border-radius: 3px; letter-spacing: 1px;
}

/* ============ 关于我们 ============ */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: stretch; }
.about-info { background: var(--bg-soft); border-radius: 8px; padding: 40px; }
.about-info h3 { margin: 0 0 24px; font-size: 26px; color: var(--primary); letter-spacing: 2px; }
.about-info ul { list-style: none; padding: 0; margin: 0; }
.about-info li { padding: 14px 0; border-bottom: 1px dashed var(--border); display: flex; gap: 12px; align-items: flex-start; }
.about-info li b { color: var(--primary); flex: 0 0 80px; }
.about-map { border-radius: 8px; overflow: hidden; min-height: 360px; background: #d8e6f4 url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><rect fill="%23d8e6f4" width="100" height="100"/></svg>') center/cover; }

/* ============ 视频中心分类列表 ============ */
.vcat-list { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.vcat { background: #fff; border-radius: 8px; overflow: hidden; box-shadow: 0 4px 16px rgba(0,0,0,.06); text-align: center; transition: .25s; }
.vcat:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(28,82,172,.14); }
.vcat video { width: 100%; aspect-ratio: 16/10; object-fit: cover; background: #0b1320; }
.vcat .name { padding: 16px; font-size: 18px; color: var(--primary); letter-spacing: 2px; }

/* ============ Footer ============ */
.footer { background: #1a2540; color: #bcc6dc; padding: 50px 0 24px; margin-top: 60px; }
.footer-top { display: grid; grid-template-columns: 1.5fr 1fr 1fr; gap: 50px; padding-bottom: 30px; border-bottom: 1px solid #2a3a5e; }
.footer-top h5 { color: #fff; font-size: 16px; margin: 0 0 18px; letter-spacing: 2px; }
.footer-top ul { list-style: none; padding: 0; margin: 0; }
.footer-top li { padding: 6px 0; }
.footer-top a:hover { color: #fff; }
.footer-brand p { line-height: 1.8; }
.footer-bottom { text-align: center; padding-top: 20px; font-size: 13px; }

/* ============ Reveal 动画 ============ */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity .8s ease, transform .8s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ============ 响应式 ============ */
@media (max-width: 980px) {
  .header { height: 64px; }
  .logo img { height: 44px; }
  .nav { position: fixed; top: 64px; right: 0; bottom: 0; width: 220px; background: #fff; flex-direction: column; padding: 20px; transform: translateX(100%); transition: .3s; box-shadow: -4px 0 20px rgba(0,0,0,.1); }
  .nav.open { transform: translateX(0); }
  .nav a { padding: 14px 12px; border-bottom: 1px solid #eee; }
  .nav a.active::after { display: none; }
  .nav-toggle { display: block; }
  .hero { margin-top: 64px; min-height: 380px; }
  .hero-content h1 { font-size: 30px; letter-spacing: 2px; }
  .hero-content p { font-size: 14px; letter-spacing: 4px; }
  .intro-inner, .about-grid { grid-template-columns: 1fr; gap: 30px; }
  .svc-grid, .vgrid, .vgrid-3, .vgrid-5, .case-grid, .vcat-list { grid-template-columns: repeat(2, 1fr); }
  .timeline::before { left: 24px; }
  .tl-item, .tl-item:nth-child(even) { flex-direction: row; padding-left: 0; }
  .tl-year { flex: 0 0 100%; text-align: left !important; padding: 0 0 10px 50px !important; }
  .tl-year .y { font-size: 26px; }
  .tl-card { flex: 0 0 100%; }
  .tl-card::before, .tl-item:nth-child(even) .tl-card::before { left: 18px !important; right: auto !important; }
  .footer-top { grid-template-columns: 1fr; gap: 24px; }
  .section-title h2 { font-size: 26px; }
}