* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --navy: #1a2b4c;
  --blue: #1559b7;
  --yellow: #ffc107;
  --red: #e63946;
  --gray-bg: #f5f7fa;
  --text: #1a2b4c;
  --text-muted: #666;
  --border: #e0e6ee;
}
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Arial, sans-serif;
  color: var(--text);
  background: #fff;
  font-size: 14px;
  line-height: 1.5;
}
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }
button { cursor: pointer; font-family: inherit; }
.container { max-width: 1280px; margin: 0 auto; padding: 0 20px; }

/* ===== 顶部信息条 ===== */
.top-bar {
  background: var(--navy);
  color: #99a8bc;
  font-size: 12px;
  padding: 8px 0;
}
.top-bar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.top-bar a { color: #fff; }
.top-bar span { margin: 0 10px; }

/* ===== 促销条 ===== */
.promo-bar {
  background: var(--yellow);
  color: var(--text);
  font-size: 13px;
  font-weight: 700;
  padding: 8px 0;
  text-align: center;
}

/* ===== 导航 ===== */
.nav {
  background: #fff;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}
.nav .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.logo {
  font-size: 24px;
  font-weight: 900;
  color: var(--navy);
}
.logo span { color: var(--red); }
.nav-menu {
  display: flex;
  gap: 30px;
  list-style: none;
}
.nav-menu a {
  color: var(--text);
  font-weight: 600;
  font-size: 14px;
}
.nav-cta {
  background: var(--red);
  color: #fff !important;
  padding: 10px 20px;
  border-radius: 4px;
  font-weight: 700;
}

/* ===== 面包屑 ===== */
.breadcrumb {
  padding: 20px 0;
  font-size: 13px;
  color: var(--text-muted);
}
.breadcrumb a { color: var(--blue); }

/* ===== 详情页布局 ===== */
.detail-layout {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 40px;
  padding-bottom: 50px;
}

/* ===== 左侧图片区 ===== */
.gallery-main {
  background: var(--gray-bg);
  border-radius: 8px;
  aspect-ratio: 4/3;
  margin-bottom: 15px;
  overflow: hidden;
}
.gallery-main img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.gallery-thumbs {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}
.thumb {
  background: var(--gray-bg);
  border-radius: 6px;
  aspect-ratio: 4/3;
  cursor: pointer;
  overflow: hidden;
  border: 2px solid transparent;
}
.thumb.active { border-color: var(--blue); }
.thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ===== 右侧信息区 ===== */
.vehicle-info {
  background: #fff;
}
.vehicle-tag {
  display: inline-block;
  background: var(--red);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 5px 12px;
  border-radius: 3px;
  margin-bottom: 12px;
}
.vehicle-info h1 {
  font-size: 28px;
  font-weight: 900;
  color: var(--navy);
  margin-bottom: 5px;
}
.vehicle-id {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.price-box {
  background: var(--gray-bg);
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 20px;
}
.price-label {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 5px;
}
.price-value {
  font-size: 32px;
  font-weight: 900;
  color: var(--red);
  margin-bottom: 3px;
}
.price-note {
  font-size: 12px;
  color: var(--text-muted);
}

.cta-buttons {
  display: grid;
  gap: 10px;
  margin-bottom: 25px;
}
.btn-primary {
  display: block;
  text-align: center;
  background: var(--yellow);
  color: var(--navy);
  padding: 14px;
  border-radius: 5px;
  font-weight: 800;
  font-size: 15px;
}
.btn-primary:hover { background: #e6a800; text-decoration: none; }
.btn-secondary {
  display: block;
  text-align: center;
  background: var(--navy);
  color: #fff;
  padding: 14px;
  border-radius: 5px;
  font-weight: 700;
  font-size: 15px;
}
.btn-secondary:hover { background: var(--blue); text-decoration: none; }

/* ===== 规格表 ===== */
.specs-section {
  margin-top: 30px;
}
.specs-section h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border);
}
.specs-table {
  width: 100%;
  border-collapse: collapse;
}
.specs-table td {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}
.specs-table td:first-child {
  color: var(--text-muted);
  width: 40%;
}

/* ===== 车辆描述 ===== */
.description-section {
  margin-top: 30px;
}
.description-section h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border);
}
.description-section p {
  color: var(--text-muted);
  line-height: 1.8;
}

/* ===== 联系卖家卡片 ===== */
.contact-card {
  background: var(--gray-bg);
  border-radius: 8px;
  padding: 20px;
  margin-top: 30px;
}
.contact-card h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 10px;
}
.contact-card p {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 15px;
}
.contact-methods {
  display: grid;
  gap: 8px;
}
.contact-methods a {
  display: block;
  padding: 10px;
  background: #fff;
  border-radius: 5px;
  font-size: 13px;
  font-weight: 600;
}

/* ===== 相似车源 ===== */
.similar-section {
  padding: 50px 0;
  background: var(--gray-bg);
}
.similar-section h2 {
  font-size: 24px;
  font-weight: 900;
  color: var(--navy);
  margin-bottom: 25px;
}
.similar-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

/* ===== CTA区 ===== */
.cta-section {
  background: var(--navy);
  padding: 50px 0;
  text-align: center;
}
.cta-section h2 {
  color: #fff;
  font-size: 28px;
  font-weight: 900;
  margin-bottom: 10px;
}
.cta-section p {
  color: #99a8bc;
  margin-bottom: 25px;
}
.cta-btn {
  display: inline-block;
  background: var(--yellow);
  color: var(--navy);
  padding: 14px 35px;
  border-radius: 5px;
  font-weight: 800;
  font-size: 16px;
}
.cta-btn:hover { background: #e6a800; text-decoration: none; }

/* ===== Footer ===== */
.footer {
  background: #0f1a2e;
  color: #99a8bc;
  padding: 50px 0 20px;
  font-size: 13px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer h4 {
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 15px;
}
.footer ul { list-style: none; }
.footer li { margin-bottom: 8px; }
.footer a { color: #99a8bc; }
.footer a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #2a3a55;
  padding-top: 20px;
  text-align: center;
  font-size: 12px;
}

/* ===== WhatsApp悬浮球 ===== */
.whatsapp-float {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 56px;
  height: 56px;
  background: #25d366;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(0,0,0,0.25);
  z-index: 1000;
  font-size: 28px;
  color: #fff;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .detail-layout {
    grid-template-columns: 1fr;
  }
  .similar-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .nav-menu {
    display: none;
  }
}
@media (max-width: 480px) {
  .similar-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .vehicle-info h1 {
    font-size: 22px;
  }
  .price-value {
    font-size: 26px;
  }
}