/* ========================================
   响应式设计样式
   遵循移动优先的设计原则
   ======================================== */

/* ========================================
   移动端汉堡菜单
   ======================================== */
.navbar-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  transition: background-color var(--transition-fast);
}

.navbar-toggle:hover {
  background-color: var(--background-secondary);
}

.hamburger {
  width: 24px;
  height: 18px;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.hamburger span {
  width: 100%;
  height: 2px;
  background-color: var(--text-primary);
  transition: all var(--transition-fast);
  border-radius: 1px;
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(6px, 6px);
}

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

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(8px, -8px);
}

/* ========================================
   小屏幕设备 (手机)
   最大宽度: 768px
   ======================================== */
@media (max-width: 768px) {
  /* 导航栏调整 */
  .navbar-container {
    padding: 0 var(--spacing-md);
  }
  
  .navbar-toggle {
    display: block;
  }
  
  .navbar-nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background-color: var(--background-primary);
    border-bottom: 1px solid var(--border-color);
    flex-direction: column;
    gap: 0;
    padding: var(--spacing-lg) 0;
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-medium);
    box-shadow: 0 4px 16px var(--shadow-light);
  }
  
  .navbar-nav.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  
  .navbar-nav li {
    padding: var(--spacing-sm) var(--spacing-lg);
  }
  
  .navbar-nav a {
    font-size: var(--font-size-lg);
    display: block;
    padding: var(--spacing-md) 0;
  }
  
  .navbar-nav a::after {
    display: none;
  }
  
  /* 容器调整 */
  .container,
  .container-narrow {
    padding: 0 var(--spacing-md);
  }
  
  /* 英雄区域调整 */
  .hero-section {
    padding: var(--spacing-2xl) 0;
  }
  
  .hero-title {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-md);
  }
  
  .hero-subtitle {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-xl);
  }
  
  /* 网格布局调整 */
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }
  
  /* 卡片调整 */
  .card {
    padding: var(--spacing-lg);
  }
  
  /* 按钮调整 */
  .btn {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: var(--font-size-lg);
    width: 100%;
    max-width: 280px;
  }
  
  /* 间距调整 */
  .section-padding {
    padding: var(--spacing-2xl) 0;
  }
}

/* ========================================
   平板设备 (竖屏)
   768px - 1024px
   ======================================== */
@media (min-width: 768px) and (max-width: 1024px) {
  .container {
    padding: 0 var(--spacing-xl);
  }
  
  .hero-title {
    font-size: var(--font-size-4xl);
  }
  
  .navbar-nav {
    gap: var(--spacing-lg);
  }
  
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ========================================
   大屏幕设备
   最小宽度: 1440px
   ======================================== */
@media (min-width: 1440px) {
  .container {
    max-width: 1400px;
  }
  
  .hero-title {
    font-size: var(--font-size-5xl);
  }
  
  .hero-subtitle {
    font-size: var(--font-size-2xl);
  }
}

/* ========================================
   触摸设备优化
   ======================================== */
@media (hover: none) and (pointer: coarse) {
  /* 增大触摸目标 */
  .btn {
    min-height: 44px;
    padding: var(--spacing-md) var(--spacing-xl);
  }
  
  .navbar-nav a {
    min-height: 44px;
    display: flex;
    align-items: center;
  }
  
  /* 移除悬停效果 */
  .card:hover {
    transform: none;
    box-shadow: 0 2px 12px var(--shadow-light);
  }
  
  .btn-primary:hover {
    transform: none;
    box-shadow: none;
  }
  
  .btn-secondary:hover {
    transform: none;
    box-shadow: 0 2px 12px var(--shadow-light);
  }
}

/* ========================================
   打印样式
   ======================================== */
@media print {
  * {
    background: white !important;
    color: black !important;
    box-shadow: none !important;
  }
  
  .navbar,
  .navbar-toggle,
  .btn {
    display: none !important;
  }
  
  .main-content {
    margin-top: 0 !important;
  }
  
  .hero-section {
    padding: var(--spacing-lg) 0 !important;
  }
  
  .card {
    border: 1px solid #ccc !important;
    page-break-inside: avoid;
  }
  
  a {
    text-decoration: underline !important;
  }
  
  .footer {
    margin-top: var(--spacing-lg) !important;
    page-break-before: always;
  }
}

/* ========================================
   高对比度模式支持
   ======================================== */
@media (prefers-contrast: high) {
  :root {
    --text-primary: #000000;
    --text-secondary: #333333;
    --border-color: #666666;
    --primary-blue: #0000EE;
    --primary-blue-hover: #0000CC;
  }
  
  .btn {
    border: 2px solid currentColor;
  }
  
  .card {
    border: 2px solid var(--border-color);
  }
}

/* ========================================
   动画减少模式支持
   ======================================== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}