/* ============================================
   Global CSS - 全局样式
   ============================================ */

/* CSS 变量 */
:root {
  /* 品牌色 */
  --color-primary: #D4232A;
  --color-primary-dark: #B01D23;
  --color-primary-light: #E8484E;
  --color-secondary: #1A3A6B;
  --color-secondary-dark: #0F2849;
  --color-secondary-light: #2A5299;

  /* 中性色 */
  --color-text: #333333;
  --color-text-light: #666666;
  --color-text-lighter: #999999;
  --color-border: #E0E0E0;
  --color-bg: #FFFFFF;
  --color-bg-light: #F5F5F5;
  --color-bg-dark: #1A1A2E;

  /* 字体 */
  --font-cn: 'Source Han Sans', 'Noto Sans SC', 'Microsoft YaHei', 'PingFang SC', sans-serif;
  --font-en: 'Roboto', 'Arial', sans-serif;
  --font-mono: 'Roboto Mono', 'Courier New', monospace;

  /* 间距 */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 5rem;
  --spacing-3xl: 8rem;

  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  /* 阴影 */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 12px 48px rgba(0, 0, 0, 0.15);

  /* 过渡 */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;

  /* 容器宽度 */
  --container-max: 1200px;
  --container-wide: 1400px;

  /* 断点 */
  --bp-mobile: 768px;
  --bp-tablet: 1024px;
  --bp-desktop: 1200px;
}

/* 容器 */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.container-wide {
  width: 100%;
  max-width: var(--container-wide);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* 通用按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 2rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: all var(--transition-base);
  cursor: pointer;
  letter-spacing: 0.02em;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(212, 35, 42, 0.35);
}

.btn-secondary {
  background-color: transparent;
  color: #ffffff;
  border: 2px solid #ffffff;
}

.btn-secondary:hover {
  background-color: #ffffff;
  color: var(--color-secondary);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn-outline:hover {
  background-color: var(--color-primary);
  color: #ffffff;
}

.btn-sm {
  padding: 0.5rem 1.25rem;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 1rem 2.5rem;
  font-size: 1.125rem;
}

/* 通用板块标题 */
.section-header {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.section-tag {
  display: inline-block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-bottom: var(--spacing-sm);
}

.section-title {
  font-size: 2.25rem;
  color: var(--color-text);
  margin-bottom: var(--spacing-sm);
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
  margin: var(--spacing-sm) auto 0;
  border-radius: 2px;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--color-text-light);
  max-width: 680px;
  margin: var(--spacing-sm) auto 0;
  line-height: 1.8;
}

/* 通用板块 */
.section {
  padding: var(--spacing-3xl) 0;
}

.section-dark {
  background-color: var(--color-bg-dark);
  color: #ffffff;
}

.section-dark .section-title {
  color: #ffffff;
}

.section-dark .section-subtitle {
  color: rgba(255, 255, 255, 0.7);
}

.section-light {
  background-color: var(--color-bg-light);
}

/* 滚动入场动画 */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in-left {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-left.visible {
  opacity: 1;
  transform: translateX(0);
}

.fade-in-right {
  opacity: 0;
  transform: translateX(40px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-right.visible {
  opacity: 1;
  transform: translateX(0);
}

/* 面包屑导航 */
.breadcrumb {
  padding: var(--spacing-md) 0;
  font-size: 0.875rem;
  color: var(--color-text-lighter);
}

.breadcrumb a {
  color: var(--color-text-light);
}

.breadcrumb a:hover {
  color: var(--color-primary);
}

.breadcrumb span {
  margin: 0 0.5rem;
}

/* 页面顶部 banner */
.page-banner {
  background: linear-gradient(135deg, var(--color-secondary-dark) 0%, var(--color-secondary) 50%, var(--color-secondary-light) 100%);
  padding: 8rem 0 4rem;
  text-align: center;
  color: #ffffff;
  position: relative;
  overflow: hidden;
}

.page-banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
  pointer-events: none;
}

.page-banner h1 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-sm);
  position: relative;
}

.page-banner p {
  font-size: 1.125rem;
  opacity: 0.85;
  position: relative;
}

/* 回到顶部 */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  background-color: var(--color-primary);
  color: #ffffff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  z-index: 999;
  cursor: pointer;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-4px);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
}

/* 响应式 */
@media (max-width: 1023px) {
  .section {
    padding: var(--spacing-2xl) 0;
  }

  .section-title {
    font-size: 1.875rem;
  }

  .page-banner h1 {
    font-size: 2rem;
  }
}

@media (max-width: 767px) {
  :root {
    --spacing-3xl: 5rem;
    --spacing-2xl: 3rem;
  }

  .container,
  .container-wide {
    padding: 0 var(--spacing-md);
  }

  .section-title {
    font-size: 1.5rem;
  }

  .section-subtitle {
    font-size: 1rem;
  }

  .page-banner {
    padding: 6rem 0 3rem;
  }

  .page-banner h1 {
    font-size: 1.75rem;
  }

  .btn {
    padding: 0.75rem 1.5rem;
    font-size: 0.9375rem;
  }
}