/* ===== 基础 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --primary: #1f5eff;
  --primary-dark: #1646b8;
  --text: #1c2333;
  --text-muted: #5a6478;
  --bg-alt: #f4f6fa;
  --border: #e3e8f0;
  --radius: 12px;
}

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--text);
  line-height: 1.7;
  background: #fff;
}

.container { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ===== 导航 ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.logo { font-size: 20px; font-weight: 700; color: var(--text); }
.logo:hover { text-decoration: none; }
.nav { display: flex; gap: 28px; }
.nav a { color: var(--text-muted); font-size: 15px; }
.nav a.active, .nav a:hover { color: var(--primary); text-decoration: none; }

/* ===== Hero ===== */
.hero {
  padding: 96px 0 88px;
  background: linear-gradient(180deg, #eef3ff 0%, #ffffff 100%);
  text-align: center;
}
.hero h1 { font-size: 40px; line-height: 1.3; margin-bottom: 16px; }
.hero p { font-size: 18px; color: var(--text-muted); max-width: 640px; margin: 0 auto 32px; }

.btn {
  display: inline-block; padding: 12px 28px; border-radius: 8px;
  font-size: 15px; margin: 0 6px; transition: .2s;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { border: 1px solid var(--primary); color: var(--primary); }
.btn-outline:hover { background: #eef3ff; }

/* ===== 区块 ===== */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { font-size: 28px; text-align: center; margin-bottom: 8px; }
.section-desc { text-align: center; color: var(--text-muted); margin-bottom: 40px; }

/* ===== 产品卡片 ===== */
.product-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}
.product-card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; transition: .2s; color: inherit;
}
.product-card:hover {
  text-decoration: none; transform: translateY(-4px);
  box-shadow: 0 12px 28px rgba(31,94,255,.12);
}
.product-thumb {
  height: 160px; display: flex; align-items: center; justify-content: center;
  color: rgba(255,255,255,.85); font-size: 15px; letter-spacing: 2px;
}
.thumb-1 { background: linear-gradient(135deg, #4f7cff, #7ba3ff); }
.thumb-2 { background: linear-gradient(135deg, #16a085, #48c9a9); }
.thumb-3 { background: linear-gradient(135deg, #e67e22, #f0b26b); }
.thumb-4 { background: linear-gradient(135deg, #8e44ad, #b07cd6); }
.product-info { padding: 18px 20px 22px; }
.product-info h3 { font-size: 17px; margin-bottom: 6px; }
.product-info p { font-size: 14px; color: var(--text-muted); margin-bottom: 12px; }
.link-arrow { font-size: 14px; color: var(--primary); font-weight: 500; }

/* ===== 关于我们 ===== */
.about-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 48px; align-items: center; }
.about-text p { margin-bottom: 14px; color: var(--text-muted); }
.about-stats { list-style: none; display: grid; gap: 20px; }
.about-stats li { text-align: center; background: #fff; border-radius: var(--radius); padding: 18px; border: 1px solid var(--border); }
.about-stats strong { display: block; font-size: 26px; color: var(--primary); }
.about-stats span { font-size: 13px; color: var(--text-muted); }

/* ===== 联系 ===== */
.contact-box { background: var(--bg-alt); border-radius: var(--radius); padding: 56px 40px; }
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; margin-top: 24px; }
.contact-grid h4 { margin-bottom: 8px; font-size: 16px; }
.contact-grid p { color: var(--text-muted); font-size: 14px; }

/* ===== 页脚 ===== */
.site-footer { background: #1c2333; color: #9aa3b5; padding: 32px 0; }
.footer-inner { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 14px; }
.site-footer a { color: #c6cdd9; }

/* ===== 商品详情页 ===== */
.detail-hero { padding: 64px 0 40px; }
.detail-hero .crumb { font-size: 14px; color: var(--text-muted); margin-bottom: 20px; }
.detail-hero h1 { font-size: 32px; margin-bottom: 10px; }
.detail-hero .subtitle { color: var(--text-muted); font-size: 17px; }

.detail-body { display: grid; grid-template-columns: 5fr 7fr; gap: 40px; padding-bottom: 72px; }
.detail-media {
  border-radius: var(--radius); min-height: 320px;
  display: flex; align-items: center; justify-content: center;
  color: rgba(255,255,255,.85); font-size: 16px; letter-spacing: 2px;
}
.detail-content h2 { font-size: 20px; margin: 28px 0 10px; }
.detail-content h2:first-child { margin-top: 0; }
.detail-content p, .detail-content li { color: var(--text-muted); font-size: 15px; }
.detail-content ul { padding-left: 20px; margin: 8px 0; }
.detail-content li { margin-bottom: 6px; }

.spec-table { width: 100%; border-collapse: collapse; margin-top: 8px; font-size: 14px; }
.spec-table th, .spec-table td { border: 1px solid var(--border); padding: 10px 14px; text-align: left; }
.spec-table th { background: var(--bg-alt); font-weight: 600; width: 140px; }

.detail-cta { margin-top: 32px; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .hero h1 { font-size: 28px; }
  .about-grid, .detail-body, .contact-grid { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; }
  .nav { gap: 16px; }
  .nav a { font-size: 13px; }
}