/* ========== 全局变量 ========== */
:root {
  --primary: #1a1a2e;
  --secondary: #16213e;
  --accent: #0f4c5c;
  --accent-light: #e8b4b8;
  --bg: #fafafa;
  --white: #ffffff;
  --text: #333333;
  --text-light: #777777;
  --shadow: 0 2px 15px rgba(0,0,0,0.08);
  --radius: 12px;
  --transition: all 0.3s ease;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

a {
  text-decoration: none;
  color: inherit;
}

.section {
  padding: 80px 0;
}

.section-title {
  text-align: center;
  font-size: 36px;
  font-weight: 300;
  color: var(--primary);
  margin-bottom: 50px;
  letter-spacing: 2px;
}

/* ========== 顶部导航 ========== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
  z-index: 1000;
  padding: 15px 0;
}

.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 1px;
}

.nav {
  display: flex;
  gap: 30px;
}

.nav a {
  font-size: 14px;
  color: var(--text-light);
  transition: var(--transition);
  position: relative;
}

.nav a:hover {
  color: var(--accent);
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: var(--transition);
}

.nav a:hover::after {
  width: 100%;
}

.btn-inquire {
  padding: 10px 24px;
  background: var(--accent);
  color: var(--white);
  border: none;
  border-radius: 30px;
  font-size: 14px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-inquire:hover {
  background: #0d3d4a;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(15, 76, 92, 0.3);
}

/* ========== Hero 横幅 ========== */
.hero {
  margin-top: 70px;
  height: 600px;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f4c5c 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.3);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: var(--white);
  padding: 20px;
}

.hero-content h1 {
  font-size: 56px;
  font-weight: 300;
  margin-bottom: 20px;
  letter-spacing: 3px;
}

.hero-content p {
  font-size: 20px;
  opacity: 0.9;
  margin-bottom: 30px;
}

.btn-primary {
  padding: 15px 40px;
  background: var(--accent);
  color: var(--white);
  border: none;
  border-radius: 30px;
  font-size: 16px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-primary:hover {
  background: #0d3d4a;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(15, 76, 92, 0.3);
}

/* ========== 产品选型 ========== */
.filter-tabs {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 40px;
}

.filter-tab {
  padding: 10px 24px;
  border: 1px solid #ddd;
  background: var(--white);
  border-radius: 30px;
  cursor: pointer;
  font-size: 14px;
  transition: var(--transition);
  color: var(--text-light);
}

.filter-tab:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.filter-tab.active {
  background: var(--primary);
  color: var(--white);
  border-color: var(--primary);
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 25px;
}

.product-card {
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  cursor: pointer;
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12);
}

.product-img {
  width: 100%;
  height: 320px;
  object-fit: cover;
  background: #f5f5f5;
}

.product-info {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.product-info h4 {
  font-size: 16px;
  font-weight: 500;
  color: var(--primary);
  line-height: 1.3;
}

.product-meta {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--text-light);
}

.product-price {
  font-size: 18px;
  font-weight: 600;
  color: var(--accent);
  margin: 5px 0;
}

.product-moq {
  font-size: 12px;
  color: var(--text-light);
  padding: 3px 10px;
  background: #f0f0f0;
  border-radius: 12px;
  display: inline-block;
}

/* ========== 关于我们 ========== */
.about-section {
  background: var(--white);
}

.about-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-text h3 {
  font-size: 28px;
  font-weight: 400;
  color: var(--primary);
  margin-bottom: 20px;
}

.about-text p {
  font-size: 15px;
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 15px;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.stat-item {
  text-align: center;
  padding: 30px;
  background: var(--bg);
  border-radius: var(--radius);
}

.stat-number {
  font-size: 48px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 10px;
}

.stat-label {
  font-size: 14px;
  color: var(--text-light);
}

/* ========== 联系我们 ========== */
.contact-section {
  background: var(--bg);
}

.contact-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
}

.contact-form h3,
.contact-info h3 {
  font-size: 24px;
  font-weight: 400;
  color: var(--primary);
  margin-bottom: 30px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 8px;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 14px;
  font-family: inherit;
  transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(15, 76, 92, 0.1);
}

.form-group textarea {
  resize: vertical;
}

.btn-submit {
  padding: 15px 40px;
  background: var(--primary);
  color: var(--white);
  border: none;
  border-radius: 8px;
  font-size: 16px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-submit:hover {
  background: #0d3d4a;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(15, 76, 92, 0.3);
}

.info-item {
  margin-bottom: 25px;
}

.info-item strong {
  display: block;
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 5px;
}

.info-item span {
  font-size: 16px;
  color: var(--primary);
}

/* ========== 页脚 ========== */
.footer {
  background: var(--primary);
  color: rgba(255, 255, 255, 0.8);
  text-align: center;
  padding: 30px 0;
  font-size: 14px;
  line-height: 2;
}

.footer a {
  color: var(--accent-light);
  transition: var(--transition);
}

.footer a:hover {
  color: var(--white);
}

/* ========== 响应式 ========== */
@media (max-width: 768px) {
  .hero {
    height: 400px;
  }

  .hero-content h1 {
    font-size: 36px;
  }

  .hero-content p {
    font-size: 16px;
  }

  .about-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .contact-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .product-grid {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
  }

  .product-img {
    height: 250px;
  }

  .nav {
    gap: 15px;
  }

  .nav a {
    font-size: 13px;
  }
}

@media (max-width: 480px) {
  .hero {
    height: 300px;
  }

  .hero-content h1 {
    font-size: 28px;
  }

  .hero-content p {
    font-size: 14px;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 28px;
    margin-bottom: 30px;
  }

  .about-stats {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .stat-number {
    font-size: 36px;
  }

  .product-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
  }

  .product-img {
    height: 180px;
  }

  .product-info {
    padding: 12px;
  }

  .product-info h4 {
    font-size: 13px;
  }

  .filter-tabs {
    gap: 8px;
  }

  .filter-tab {
    padding: 8px 16px;
    font-size: 13px;
  }
}