/* ===== 基础变量 ===== */
:root {
  --color-primary: #1a3a5c;
  --color-primary-light: #2a5a8c;
  --color-accent: #c8a45c;
  --color-accent-light: #e8c87a;
  --color-text: #2c3e50;
  --color-text-light: #6b7c93;
  --color-bg: #ffffff;
  --color-bg-alt: #f7f9fc;
  --color-border: #e8edf3;
  --font-family: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'WenQuanYi Micro Hei', sans-serif;
  --shadow-sm: 0 2px 8px rgba(26, 58, 92, 0.06);
  --shadow-md: 0 8px 30px rgba(26, 58, 92, 0.1);
  --shadow-lg: 0 20px 60px rgba(26, 58, 92, 0.12);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: 0.3s ease;
}

/* ===== 重置 ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition);
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  display: block;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 36px;
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  letter-spacing: 0.5px;
}

.btn-primary {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}

.btn-primary:hover {
  background: var(--color-accent-light);
  border-color: var(--color-accent-light);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(200, 164, 92, 0.35);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.6);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: #fff;
}

.btn-block {
  width: 100%;
}

/* ===== 导航 ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.98);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.header.scrolled {
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--color-primary);
  color: var(--color-accent);
  font-size: 18px;
  font-weight: 700;
  border-radius: var(--radius);
}

.logo-text {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-primary);
  letter-spacing: 2px;
}

.nav {
  display: flex;
  gap: 36px;
}

.nav-link {
  font-size: 15px;
  color: var(--color-text-light);
  font-weight: 400;
  position: relative;
  padding: 4px 0;
}

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

.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-primary);
  transition: all var(--transition);
}

/* ===== 首屏 ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 120px 0 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--color-primary) 0%, #0f2847 50%, #1a3a5c 100%);
  z-index: -1;
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 80%;
  height: 150%;
  background: radial-gradient(ellipse, rgba(200, 164, 92, 0.08) 0%, transparent 70%);
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 200px;
  background: linear-gradient(to top, var(--color-bg), transparent);
}

.hero-content {
  text-align: center;
  color: #fff;
}

.hero-tag {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 4px;
  color: var(--color-accent);
  margin-bottom: 24px;
  font-weight: 500;
}

.hero-title {
  font-size: clamp(48px, 8vw, 80px);
  font-weight: 700;
  letter-spacing: 12px;
  margin-bottom: 16px;
  line-height: 1.2;
}

.hero-subtitle {
  font-size: clamp(18px, 3vw, 24px);
  font-weight: 300;
  letter-spacing: 4px;
  margin-bottom: 20px;
  opacity: 0.9;
}

.hero-desc {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.7);
  max-width: 600px;
  margin: 0 auto 40px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 64px;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
  padding-top: 48px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.stat {
  text-align: center;
}

.stat-num {
  display: block;
  font-size: 32px;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
  letter-spacing: 1px;
}

/* ===== 通用区块 ===== */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 4px;
  color: var(--color-accent);
  font-weight: 500;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 16px;
  letter-spacing: 2px;
}

.section-desc {
  font-size: 16px;
  color: var(--color-text-light);
  max-width: 500px;
  margin: 0 auto;
}

/* ===== 产品中心 ===== */
.products {
  background: var(--color-bg-alt);
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.product-card {
  background: var(--color-bg);
  padding: 40px 32px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.product-icon {
  width: 56px;
  height: 56px;
  color: var(--color-accent);
  margin-bottom: 24px;
}

.product-icon svg {
  width: 100%;
  height: 100%;
}

.product-card h3 {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.product-card p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.8;
  margin-bottom: 20px;
}

.product-link {
  font-size: 14px;
  color: var(--color-accent);
  font-weight: 500;
  transition: color var(--transition);
}

.product-link:hover {
  color: var(--color-primary);
}

/* ===== 批发优势 ===== */
.advantage-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}

.advantage-item {
  text-align: center;
  padding: 40px 24px;
}

.advantage-num {
  font-size: 48px;
  font-weight: 700;
  color: rgba(200, 164, 92, 0.2);
  margin-bottom: 16px;
  line-height: 1;
}

.advantage-item h3 {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.advantage-item p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.8;
}

/* ===== 关于我们 ===== */
.about {
  background: var(--color-bg-alt);
}

.about-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.about-content .section-tag {
  display: block;
  text-align: left;
}

.about-content .section-title {
  text-align: left;
  margin-bottom: 24px;
}

.about-content p {
  font-size: 15px;
  color: var(--color-text-light);
  margin-bottom: 16px;
  line-height: 1.9;
}

.about-features {
  margin-top: 32px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.about-features li {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 16px 20px;
  background: var(--color-bg);
  border-radius: var(--radius);
  border-left: 3px solid var(--color-accent);
}

.about-features strong {
  font-size: 15px;
  color: var(--color-primary);
  white-space: nowrap;
}

.about-features span {
  font-size: 14px;
  color: var(--color-text-light);
}

.about-visual {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.about-card {
  background: var(--color-primary);
  border-radius: var(--radius-lg);
  padding: 48px 40px;
  color: #fff;
}

.about-card-secondary {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  color: var(--color-text);
  margin-left: 40px;
}

.about-card-label {
  display: block;
  font-size: 12px;
  letter-spacing: 3px;
  color: var(--color-accent);
  margin-bottom: 12px;
  font-weight: 500;
}

.about-card p {
  font-size: 22px;
  font-weight: 500;
  line-height: 1.6;
  letter-spacing: 1px;
}

.about-card-secondary .about-card-label {
  color: var(--color-text-light);
}

.about-card-secondary p {
  color: var(--color-primary);
}

/* ===== 联系我们 ===== */
.contact-inner {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 64px;
  align-items: start;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.contact-item {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.contact-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg-alt);
  border-radius: var(--radius);
  color: var(--color-accent);
}

.contact-icon svg {
  width: 22px;
  height: 22px;
}

.contact-item h4 {
  font-size: 14px;
  color: var(--color-text-light);
  font-weight: 400;
  margin-bottom: 4px;
}

.contact-item p {
  font-size: 16px;
  color: var(--color-primary);
  font-weight: 500;
}

.contact-form {
  background: var(--color-bg-alt);
  padding: 40px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

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

.form-group label {
  display: block;
  font-size: 14px;
  color: var(--color-text);
  margin-bottom: 8px;
  font-weight: 500;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  font-size: 15px;
  font-family: var(--font-family);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-bg);
  color: var(--color-text);
  transition: border-color var(--transition);
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--color-accent);
}

.form-group textarea {
  resize: vertical;
  min-height: 100px;
}

/* ===== 页脚 ===== */
.footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.7);
  padding-top: 64px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.2fr 2fr;
  gap: 64px;
  padding-bottom: 48px;
}

.footer-brand .logo-text {
  color: #fff;
}

.footer-brand p {
  margin-top: 16px;
  font-size: 14px;
  line-height: 1.8;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.footer-col h4 {
  font-size: 15px;
  color: #fff;
  font-weight: 500;
  margin-bottom: 20px;
  letter-spacing: 1px;
}

.footer-col a,
.footer-col span {
  display: block;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: 10px;
  transition: color var(--transition);
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 24px 0;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.4);
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .product-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .advantage-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-inner {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .contact-inner {
    grid-template-columns: 1fr;
    gap: 48px;
  }
}

@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--color-bg);
    flex-direction: column;
    padding: 24px;
    gap: 0;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-120%);
    opacity: 0;
    transition: all var(--transition);
    pointer-events: none;
  }

  .nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-link {
    padding: 14px 0;
    border-bottom: 1px solid var(--color-border);
  }

  .nav-toggle {
    display: flex;
  }

  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .nav-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .hero-title {
    letter-spacing: 6px;
  }

  .hero-stats {
    gap: 32px;
  }

  .product-grid {
    grid-template-columns: 1fr;
  }

  .advantage-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .about-card-secondary {
    margin-left: 0;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .footer-links {
    grid-template-columns: 1fr 1fr;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 480px) {
  .section {
    padding: 72px 0;
  }

  .footer-links {
    grid-template-columns: 1fr;
  }

  .contact-form {
    padding: 24px;
  }
}