/* ========== 动画关键帧 ========== */
 @keyframes fadeInUp {
     from {
         opacity: 0;
         transform: translateY(30px);
     }
     to {
         opacity: 1;
         transform: translateY(0);
     }
 }
 @keyframes fadeIn {
     from {
         opacity: 0;
     }
     to {
         opacity: 1;
     }
 }
 /* 卡片默认动画 */
 .card {
     opacity: 0;
     animation: fadeInUp 0.8s ease forwards;
     animation-delay: 0.1s;
 }
 .main-nav {
     max-width: 1200px;
     margin: 0 auto;
     padding: 10px 0;
 }
 .main-nav > ul {
     display: flex;
     flex-wrap: wrap;
     gap: 25px;
     justify-content: center;
     position: relative;
 }
 .main-nav a {
     color: white;
     font-size: 24px;
     font-weight: 700;
     transition: color 0.3s, transform 0.3s;
     display: block;
     padding: 8px 0;
 }
 .main-nav a:hover {
     color: #80bfff;
     transform: translateY(-2px);
 }
 /* 二级菜单 */
 .main-nav ul li {
     position: relative;
 }
 .main-nav ul li ul {
     position: absolute;
     top: 100%;
     left: 0;
     min-width: 160px;
     background: #0a4ea0;
     border-radius: 6px;
     padding: 8px 0;
     box-shadow: 0 3px 8px rgba(0, 0, 0, 0.2);
     opacity: 0;
     visibility: hidden;
     transform: translateY(10px);
     transition: all 0.3s;
     z-index: 999;
 }
 .main-nav ul li ul li {
     padding: 0 12px;
 }
 .main-nav ul li ul li a {
     font-size: 16px;
     padding: 6px 0;
     white-space: nowrap;
 }
 .main-nav ul li ul li ul {
     top: 0;
     left: 100%;
     transform: translateX(10px);
 }
 .main-nav ul li:hover > ul {
     opacity: 1;
     visibility: visible;
     transform: translate(0);
 }
 /* 内容布局 */
 .container {
     max-width: 1600px;
     margin: 20px auto;
     padding: 0 20px;
     width: 100%;
 }
 .row {
     display: flex;
     flex-wrap: wrap;
     gap: 20px;
     margin-bottom: 20px;
     width: 100%;
     align-items: stretch;
 }
 /* 文章内容区域 */
 .col-content {
     flex: 1;
     width: 100%;
     display: flex;
     flex-direction: column;
 }
 .card {
     background: white;
     border-radius: 16px;
     padding: 7px 18px 18px 18px;
     box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
     border: 6px solid #cce7ff;
     overflow: hidden;
     display: flex;
     flex-direction: column;
     width: 100%;
     min-height: 0;
 }
 .card:hover {
     box-shadow: 0 8px 16px rgba(0, 0, 0, 0.15);
     transform: translateY(-3px);
 }
 /* ==================== 文章内容页专属样式 ==================== */
 /* 面包屑导航 */
 .article-bread {
     font-size: 15px;
     color: #666;
     margin-bottom: 20px;
     padding-bottom: 10px;
     border-bottom: 1px dashed #cce7ff;
 }
 .article-bread a {
     color: #0a4ea0;
 }
 .article-bread a:hover {
     text-decoration: underline;
 }
 /* 文章标题 */
 .article-title {
     font-size: 32px;
     font-weight: bold;
     color: #333;
     text-align: center;
     line-height: 1.4;
     margin: 10px 0 20px;
 }
 /* 文章信息栏 */
 .article-info {
     display: flex;
     justify-content: center;
     align-items: center;
     gap: 30px;
     color: #666;
     font-size: 15px;
     margin-bottom: 30px;
     padding-bottom: 20px;
     border-bottom: 1px solid #cce7ff;
     flex-wrap: wrap;
 }
 /* 文章正文 */
 .article-body {
     font-size: 17px;
     line-height: 1.8;
     color: #333;
 }
 .article-body p {
     margin-bottom: 20px;
     text-indent: 2em; /* 段落首行缩进 */
 }
 .article-body img {
     max-width: 100%;
     height: auto;
     display: block;
     margin: 20px auto;
     border-radius: 8px;
     box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
 }
 /* ==================== 响应式适配 ==================== */
 @media (max-width: 1200px) {
     .main-nav a {
         font-size: 20px;
     }
     .main-nav > ul {
         gap: 18px;
     }
 }
 @media (max-width: 992px) {
     .main-nav a {
         font-size: 18px;
     }
     .article-title {
         font-size: 28px;
     }
 }
 @media (max-width: 768px) {
     .main-nav > ul {
         display: none;
         flex-direction: column;
         align-items: center;
         gap: 5px;
         background: rgba(10, 78, 160, 0.95);
         padding: 20px;
         border-radius: 12px;
         width: 100%;
     }
     .main-nav > ul.show {
         display: flex;
     }
     .main-nav a {
         font-size: 18px;
     }
     .main-nav ul li ul {
         position: static;
         background: rgba(255, 255, 250.1);
         border-radius: 8px;
         box-shadow: none;
         opacity: 1;
         visibility: visible;
         transform: none;
         text-align: center;
         width: 220px;
         margin: 8px 0;
         padding: 10px 0;
         display: none;
     }
     .main-nav ul li ul.show {
         display: block;
     }
     .main-nav ul li ul li a {
         font-size: 16px;
         color: #ffffff;
         padding: 6px 12px;
     }
     .main-nav ul li ul li a:hover {
         color: #80bfff;
     }
     .container {
         margin: 10px auto 0 auto;
     }
     .row {
         margin-bottom: 10px;
         gap: 15px;
     }
     .card {
         padding: 7px 12px 12px 12px;
         border-width: 4px;
     }
     .article-title {
         font-size: 24px;
     }
     .article-info {
         gap: 15px;
         font-size: 14px;
     }
     .article-body {
         font-size: 16px;
     }
 }
 @media (max-width: 480px) {
     .article-title {
         font-size: 20px;
     }
 }