:root {
     --primary-color: #e63946;
     --secondary-color: #f4a261;
     --text-color: #333;
     --light-gray: #f5f5f5;
     --medium-gray: #e0e0e0;
     --dark-gray: #757575;
     --white: #fff;
     --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
 }
 
 * {
     margin: 0;
     padding: 0;
     box-sizing: border-box;
     font-family: "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
 }
 
 body {
     background-color: #f9f9f9;
     color: var(--text-color);
     line-height: 1.6;
 }
 
 .container {
     width: 100%;
     max-width: 1200px;
     margin: 0 auto;
     padding: 0 20px;
 }
 
 /* 导航栏样式 */
 .navbar {
     background-color: var(--white);
     box-shadow: var(--shadow);
     position: sticky;
     top: 0;
     z-index: 100;
 }
 
 .nav-container {
     display: flex;
     justify-content: space-between;
     align-items: center;
     padding: 15px 0;
 }
 
 .logo {
     font-size: 24px;
     font-weight: bold;
     color: var(--primary-color);
 }
 
 .nav-links {
     display: flex;
     gap: 25px;
 }
 
 .nav-links a {
     text-decoration: none;
     color: var(--text-color);
     font-weight: 500;
     transition: color 0.3s;
 }
 
 .nav-links a:hover {
     color: var(--primary-color);
 }
 
 .user-actions {
     display: flex;
     align-items: center;
     gap: 15px;
 }
 
 .search-box {
     position: relative;
     display: flex;
     align-items: center;
     background-color: var(--light-gray);
     border-radius: 20px;
     padding: 5px 15px;
     width: 200px;
     transition: width 0.3s;
 }
 
 .search-box:hover, .search-box:focus-within {
     width: 250px;
 }
 
 .search-box input {
     background: transparent;
     border: none;
     outline: none;
     width: 100%;
     padding: 8px 0;
 }
 
 .search-box i {
     color: var(--dark-gray);
     margin-right: 8px;
 }
 
 /* Banner区域样式 */
 .banner {
     background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.6)), url('https://picsum.photos/1600/500?random=501') no-repeat center center/cover;
     height: 400px;
     display: flex;
     align-items: center;
     margin-bottom: 30px;
     border-radius: 10px;
     overflow: hidden;
 }
 
 .banner-content {
     color: var(--white);
     max-width: 700px;
 }
 
 .banner-content h1 {
     font-size: 36px;
     font-weight: bold;
     margin-bottom: 15px;
     line-height: 1.3;
 }
 
 .banner-content p {
     font-size: 18px;
     margin-bottom: 25px;
     opacity: 0.9;
 }
 
 .banner-button {
     display: inline-block;
     background-color: var(--primary-color);
     color: var(--white);
     padding: 12px 30px;
     text-decoration: none;
     border-radius: 30px;
     font-weight: 500;
     transition: background-color 0.3s;
 }
 
 .banner-button:hover {
     background-color: #c12531;
 }
 
 /* 内容区域布局 */
 .content {
     display: flex;
     gap: 30px;
     margin-bottom: 50px;
 }
 
 .main-content {
     flex: 2;
 }
 
 .sidebar {
     flex: 1;
     min-width: 300px;
 }
 
 /* 卡片样式 */
 .card {
     background-color: var(--white);
     border-radius: 10px;
     box-shadow: var(--shadow);
     margin-bottom: 30px;
     overflow: hidden;
 }
 
 .card-header {
     display: flex;
     align-items: center;
     padding: 15px 20px;
     border-bottom: 1px solid var(--medium-gray);
 }
 
 .avatar {
     width: 50px;
     height: 50px;
     border-radius: 50%;
     overflow: hidden;
     margin-right: 15px;
 }
 
 .avatar img {
     width: 100%;
     height: 100%;
     object-fit: cover;
 }
 
 .user-info {
     flex: 1;
 }
 
 .username {
     font-weight: bold;
     font-size: 16px;
 }
 
 .time {
     color: var(--dark-gray);
     font-size: 14px;
 }
 
 .card-content {
     padding: 20px;
 }
 
 .card-content h3 {
     font-size: 20px;
     margin-bottom: 15px;
     color: var(--text-color);
 }
 
 .card-content p {
     color: var(--dark-gray);
     margin-bottom: 15px;
 }
 
 .card-stats {
     display: flex;
     justify-content: space-between;
     align-items: center;
     padding: 15px 20px;
     background-color: var(--light-gray);
     border-top: 1px solid var(--medium-gray);
 }
 
 .card-stats div:first-child {
     color: var(--dark-gray);
     font-size: 14px;
 }
 
 .card-actions {
     display: flex;
     gap: 15px;
 }
 
 .card-actions span {
     display: flex;
     align-items: center;
     color: var(--dark-gray);
     font-size: 14px;
 }
 
 .card-actions span i {
     margin-right: 5px;
 }
 
 .comments {
     padding: 15px 20px;
     border-top: 1px solid var(--medium-gray);
 }
 
 .comment {
     margin-bottom: 15px;
     padding-bottom: 15px;
     border-bottom: 1px dashed var(--medium-gray);
 }
 
 .comment:last-child {
     margin-bottom: 0;
     padding-bottom: 0;
     border-bottom: none;
 }
 
 .comment-user {
     font-weight: 500;
     margin-right: 8px;
     color: var(--primary-color);
 }
 
 .comment-content {
     color: var(--text-color);
 }
 
 /* 话题卡片样式 */
 .topic-card {
     background-color: var(--white);
     border-radius: 10px;
     box-shadow: var(--shadow);
     padding: 20px;
     margin-bottom: 30px;
 }
 
 .topic-card h3 {
     font-size: 18px;
     margin-bottom: 15px;
     color: var(--primary-color);
     border-left: 4px solid var(--primary-color);
     padding-left: 10px;
 }
 
 .topic-card p {
     color: var(--text-color);
 }
 
 /* 侧边栏部分样式 */
 .sidebar-section {
     background-color: var(--white);
     border-radius: 10px;
     box-shadow: var(--shadow);
     padding: 20px;
     margin-bottom: 30px;
 }
 
 .sidebar-title {
     display: flex;
     align-items: center;
     font-size: 18px;
     font-weight: bold;
     margin-bottom: 15px;
     padding-bottom: 10px;
     border-bottom: 1px solid var(--medium-gray);
 }
 
 .sidebar-title i {
     color: var(--primary-color);
     margin-right: 10px;
 }
 
 .hot-list {
     list-style: none;
 }
 
 .hot-item {
     display: flex;
     align-items: center;
     padding: 10px 0;
     border-bottom: 1px solid var(--light-gray);
 }
 
 .hot-item:last-child {
     border-bottom: none;
 }
 
 .hot-index {
     display: flex;
     align-items: center;
     justify-content: center;
     width: 25px;
     height: 25px;
     border-radius: 50%;
     background-color: var(--primary-color);
     color: var(--white);
     font-size: 14px;
     font-weight: bold;
     margin-right: 10px;
     flex-shrink: 0;
 }
 
 .hot-content {
     flex: 1;
     font-size: 14px;
     display: flex;
     align-items: center;
 }
 
 .hot-tag {
     display: inline-block;
     background-color: var(--secondary-color);
     color: var(--white);
     padding: 2px 8px;
     border-radius: 10px;
     font-size: 10px;
     margin-left: 5px;
     flex-shrink: 0;
 }
 
 .follow-item {
     display: flex;
     align-items: center;
     padding: 10px 0;
     border-bottom: 1px solid var(--light-gray);
 }
 
 .follow-item:last-child {
     border-bottom: none;
 }
 
 .follow-avatar {
     width: 50px;
     height: 50px;
     border-radius: 50%;
     overflow: hidden;
     margin-right: 15px;
     background-color: var(--light-gray);
 }
 
 .follow-info {
     flex: 1;
 }
 
 .follow-name {
     font-weight: bold;
     font-size: 14px;
     margin-bottom: 3px;
 }
 
 .follow-desc {
     color: var(--dark-gray);
     font-size: 12px;
 }
 
 .follow-button {
     background-color: var(--white);
     color: var(--primary-color);
     border: 1px solid var(--primary-color);
     padding: 5px 15px;
     border-radius: 20px;
     font-size: 12px;
     font-weight: 500;
     transition: all 0.3s;
 }
 
 .follow-button:hover {
     background-color: var(--primary-color);
     color: var(--white);
 }
 
 .subscribe-form {
     display: flex;
     margin-top: 15px;
 }
 
 .subscribe-form input {
     flex: 1;
     padding: 10px;
     border: 1px solid var(--medium-gray);
     border-right: none;
     border-radius: 5px 0 0 5px;
     outline: none;
 }
 
 .subscribe-form button {
     background-color: var(--primary-color);
     color: var(--white);
     border: none;
     padding: 0 20px;
     border-radius: 0 5px 5px 0;
     font-weight: 500;
     cursor: pointer;
 }
 
 .subscribe-tip {
     font-size: 12px;
     color: var(--dark-gray);
     margin-top: 10px;
     text-align: center;
 }
 
 /* 页脚样式 */
 .footer {
     background-color: var(--white);
     box-shadow: 0 -4px 6px rgba(0, 0, 0, 0.1);
     padding: 50px 0 20px;
     margin-top: 50px;
 }
 
 .footer-container {
     display: flex;
     flex-wrap: wrap;
     gap: 50px;
 }
 
 .footer-section {
     flex: 1;
     min-width: 200px;
 }
 
 .footer-section h4 {
     font-size: 18px;
     margin-bottom: 20px;
     position: relative;
     padding-bottom: 10px;
 }
 
 .footer-section h4::after {
     content: '';
     position: absolute;
     left: 0;
     bottom: 0;
     width: 40px;
     height: 3px;
     background-color: var(--primary-color);
 }
 
 .footer-section ul {
     list-style: none;
 }
 
 .footer-section li {
     margin-bottom: 10px;
 }
 
 .footer-section a {
     text-decoration: none;
     color: var(--dark-gray);
     transition: color 0.3s;
 }
 
 .footer-section a:hover {
     color: var(--primary-color);
 }
 
 .footer-bottom {
     margin-top: 40px;
     padding-top: 20px;
     border-top: 1px solid var(--medium-gray);
     display: flex;
     justify-content: space-between;
     align-items: center;
     flex-wrap: wrap;
 }
 
 .footer-bottom div {
     margin-bottom: 10px;
 }
 
 .footer-links a {
     margin-left: 15px;
     color: var(--dark-gray);
     text-decoration: none;
     transition: color 0.3s;
 }
 
 .footer-links a:hover {
     color: var(--primary-color);
 }
 
 /* 模态框样式 */
 .modal {
     display: none;
     position: fixed;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background-color: rgba(0, 0, 0, 0.5);
     z-index: 1000;
     align-items: center;
     justify-content: center;
 }
 
 .modal-content {
     background-color: var(--white);
     padding: 30px;
     border-radius: 10px;
     max-width: 600px;
     width: 90%;
     position: relative;
 }
 
 .close-modal {
     position: absolute;
     top: 15px;
     right: 15px;
     font-size: 24px;
     color: var(--dark-gray);
     cursor: pointer;
 }
 
 .close-modal:hover {
     color: var(--primary-color);
 }
 
 .modal h2 {
     font-size: 24px;
     margin-bottom: 20px;
     color: var(--text-color);
 }
 
 .modal p {
     color: var(--dark-gray);
     line-height: 1.8;
 }
 
 /* 回到顶部按钮 */
 .back-to-top {
     position: fixed;
     bottom: 30px;
     right: 30px;
     width: 50px;
     height: 50px;
     border-radius: 50%;
     background-color: var(--primary-color);
     color: var(--white);
     display: flex;
     align-items: center;
     justify-content: center;
     cursor: pointer;
     box-shadow: var(--shadow);
     opacity: 0;
     visibility: hidden;
     transition: all 0.3s;
     z-index: 99;
 }
 
 .back-to-top.visible {
     opacity: 1;
     visibility: visible;
 }
 
 /* 响应式设计 */
 @media (max-width: 992px) {
     .content {
  flex-direction: column;
     }
     
     .sidebar {
  min-width: auto;
     }
     
     .banner {
  height: 300px;
     }
     
     .banner-content h1 {
  font-size: 28px;
     }
     
     .footer-container {
  gap: 30px;
     }
 }
 
 @media (max-width: 768px) {
     .nav-links {
  display: none;
     }
     
     .search-box {
  width: 150px;
     }
     
     .search-box:hover, .search-box:focus-within {
  width: 200px;
     }
     
     .banner-content h1 {
  font-size: 24px;
     }
     
     .banner-content p {
  font-size: 16px;
     }
     
     .footer-container {
  flex-direction: column;
  gap: 20px;
     }
 }