/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    font-family: "Helvetica Neue", Arial, sans-serif;
    background-color: #f9f9f9;
    color: #333;
    line-height: 1.6;
  }
  
  .container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
  }
  
  /* 导航栏 */
  .navbar {
    background-color: #ffffff;
    border-bottom: 1px solid #eaeaea;
    position: sticky;
    top: 0;
    z-index: 1000;
  }
  .navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
  }
  .logo {
    font-size: 1.5rem;
    font-weight: bold;
  }
  .nav-links a {
    margin: 0 1rem;
    text-decoration: none;
    color: #555;
  }
  .nav-links a:hover {
    color: #000;
  }
  .user-actions {
    display: flex;
    align-items: center;
  }
  .search-box {
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    margin-right: 1rem;
  }
  .btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
  }
  .btn.login {
    background-color: #4caf50;
    color: #fff;
    margin-right: 0.5rem;
  }
  .btn.register {
    background-color: #2196f3;
    color: #fff;
  }
  
  /* 焦点横幅 */
  .hero {
    background: url('banner.jpg') no-repeat center center/cover;
    text-align: center;
    padding: 4rem 0;
    margin-bottom: 2rem;
  }
  .hero h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
  }
  .hero p {
    font-size: 1.2rem;
  }
  
  /* 文章卡片区 */
  .articles {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
  }
  .card {
    background-color: #fff;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
  }
  .card h2 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
  }
  .card p {
    flex-grow: 1;
    margin-bottom: 1rem;
  }
  .tag {
    display: inline-block;
    background-color: #e0e0e0;
    padding: 0.3rem 0.6rem;
    border-radius: 12px;
    font-size: 0.8rem;
    margin-right: 0.5rem;
  }
  .read-more {
    align-self: flex-end;
    text-decoration: none;
    background-color: #ff9800;
    color: #fff;
    padding: 0.5rem 1rem;
    border-radius: 4px;
  }
  .read-more:hover {
    background-color: #fb8c00;
  }
  
  /* 侧边栏 */
  .sidebar {
    margin-top: 2rem;
    background-color: #fff;
    padding: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  }
  .widget + .widget {
    margin-top: 1.5rem;
  }
  .widget h3 {
    margin-bottom: 1rem;
    font-size: 1.1rem;
  }
  .tags a {
    display: inline-block;
    margin: 0.2rem;
    text-decoration: none;
    color: #2196f3;
    font-size: 0.9rem;
  }
  
  /* 页脚 */
  .footer {
    background-color: #ffffff;
    border-top: 1px solid #eaeaea;
    text-align: center;
    padding: 1rem 0;
    margin-top: 2rem;
  }
  .footer p a {
    color: #555;
    text-decoration: none;
    margin: 0 0.5rem;
  }
  .footer p a:hover {
    color: #000;
  }
  
  /* 响应式 */
  @media (max-width: 768px) {
    .navbar .container {
      flex-direction: column;
      align-items: flex-start;
    }
    .nav-links {
      margin-top: 1rem;
    }
    .user-actions {
      margin-top: 1rem;
      width: 100%;
    }
    .search-box {
      width: 100%;
      margin-bottom: 0.5rem;
    }
  }