* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        
        body {
            font-family: "宋体", SimSun, serif;
            background: linear-gradient(135deg, #f5f7fa 0%, #e4efe9 100%);
            color: #333;
            line-height: 1.6;
            min-height: 100vh;
            padding: 20px;
        }
        
        .container {
            max-width: 1800px;
            margin: 0 auto;
        }
        
        /* 内容区域 */
        .main-content {
            background:white;
            
            border-radius: 15px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
            padding: 25px;
        }
        
        header {
            text-align: center;
            margin-bottom: 0px;
            padding-bottom: 0px;
            border-bottom: 1px solid #eaeaea;
        }
        
        h1 {
            font-size: 36px;
            color: #2c3e50;
            margin-bottom: 2px;
            text-shadow: 1px 1px 2px rgba(0,0,0,0.1);
        }
        
        .subtitle {
            color:white;
            font-size: 16px;
        }
        
        .controls {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 0px;
            flex-wrap: wrap;
            gap: 15px;
        }
        
        .left-controls {
            display: flex;
            align-items: center;
            gap: 20px;
            flex-wrap: wrap;
        }
        
        .grade-selector {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        select {
            padding: 10px 15px;
            border: 1px solid #ddd;
            border-radius: 8px;
            font-family: "宋体", SimSun, serif;
            font-size: 16px;
            background-color: white;
            cursor: pointer;
            box-shadow: 0 2px 5px rgba(0,0,0,0.05);
        }
        
        .stats-row {
            display: flex;
            gap: 15px;
            flex-wrap: wrap;
        }
        
        .stat-item {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 10px 15px;
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
        }
        
        .stat-item:nth-child(1) {
            background-color: #e8f4fd; /* 卡片总数 - 浅蓝色 */
        }
        
        .stat-item:nth-child(2) {
            background-color: #e8f8f0; /* 活跃学校 - 浅绿色 */
        }
        
        .stat-item:nth-child(3) {
            background-color: #fff5e6; /* 即将到期 - 浅橙色 */
        }
        
        .stat-item:nth-child(4) {
            background-color: #f9ebea; /* 已过期 - 浅红色 */
        }
        
        .stat-label {
            color: #7f8c8d;
            font-size: 14px;
        }
        
        .stat-value {
            font-family: "Times New Roman", Times, serif;
            font-weight: bold;
            color: #2c3e50;
            font-size: 16px;
        }
        
        .add-school-btn {
            background: linear-gradient(to right, #3498db, #2c3e50);
            color: white;
            border: none;
            border-radius: 8px;
            padding: 12px 25px;
            font-family: "宋体", SimSun, serif;
            font-size: 16px;
            cursor: pointer;
            transition: all 0.3s;
            box-shadow: 0 4px 10px rgba(52, 152, 219, 0.3);
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        .add-school-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 15px rgba(52, 152, 219, 0.4);
        }
        
        .stats-container {
            margin-bottom: 30px;
        }
        
        .grade-stats-row {
            display: flex;
            flex-wrap: wrap;
            gap: 15px;
            justify-content: space-between;
        }
        
        .grade-stat-item {
            display: flex;
            padding: 12px 20px;
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
            min-width: 120px;
            justify-content: space-between;
            align-items: center;
            background-color: #f8f9fa; /* 年级统计 - 浅灰色 */
        }
        
        .grade-name {
            color: #7f8c8d;
            font-size: 14px;
        }
        
        .grade-count {
            font-family: "Times New Roman", Times, serif;
            font-weight: bold;
            color: #2c3e50;
            font-size: 18px;
        }
        
        /* 学校卡片区域 - 每行固定显示5个卡片 */
        .schools-container {
            display: grid;
            grid-template-columns: repeat(5, 1fr);
            gap: 20px;
        }
        
        .school-card {
            background: white;
            border-radius: 12px;
            box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
            padding: 18px;
            transition: all 0.3s ease;
            cursor: pointer;
            position: relative;
            overflow: hidden;
            border-left: 5px solid #2ecc71;
            height: 180px;
            display: flex;
            flex-direction: column;
        }
        
        .school-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.12);
        }
        
        .school-card.warning {
            background-color: #fff5e6;
            border-left: 5px solid #f39c12;
        }
        
        .school-card.normal {
            background-color: #f0f9ff;
            border-left: 5px solid #3498db;
        }
        
        .school-card.expired {
            background-color: #f8f9fa;
            border-left: 5px solid #95a5a6;
        }
        
        .school-card.warning::before {
            content: "即将到期";
            position: absolute;
            top: 10px;
            right: -25px;
            background: #f39c12;
            color: white;
            padding: 5px 30px;
            font-size: 12px;
            transform: rotate(45deg);
        }
        
        .school-card.expired::before {
            content: "已到期";
            position: absolute;
            top: 10px;
            right: -25px;
            background: #95a5a6;
            color: white;
            padding: 5px 30px;
            font-size: 12px;
            transform: rotate(45deg);
        }
        
        .school-name {
            font-size: 18px;
            font-weight: bold;
            color: #2c3e50;
            margin-bottom: 10px;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        .school-name i {
            color: #3498db;
        }
        
        .school-info {
            display: flex;
            flex-direction: column;
            gap: 8px;
            flex: 1;
        }
        
        .info-row {
            display: flex;
            justify-content: space-between;
        }
        
        .info-label {
            color: #7f8c8d;
            font-size: 14px;
        }
        
        .info-value {
            font-family: "Times New Roman", Times, serif;
            font-weight: bold;
            font-size: 14px;
        }
        
        .remaining-days {
            color: #e74c3c;
            font-weight: bold;
        }
        
        .normal-days {
            color: #2ecc71;
            font-weight: bold;
        }
        
        .expired-days {
            color: #95a5a6;
            font-weight: bold;
        }
        
        /* 弹窗样式 */
        .modal {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.5);
            z-index: 1000;
            justify-content: center;
            align-items: center;
        }

        .modal-content {
            background: white;
            border-radius: 15px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
            width: 90%;
            max-width: 500px;
            max-height: 90vh;
            overflow-y: auto;
            padding: 25px;
            position: relative;
        }

        .close-btn {
            position: absolute;
            top: 15px;
            right: 20px;
            font-size: 24px;
            cursor: pointer;
            color: #7f8c8d;
            transition: color 0.3s;
        }

        .close-btn:hover {
            color: #e74c3c;
        }
        
        .form-group {
            margin-bottom: 20px;
        }
        
        label {
            display: block;
            margin-bottom: 8px;
            font-weight: bold;
            color: #2c3e50;
        }
        
        input, textarea, select {
            width: 100%;
            padding: 12px;
            border: 1px solid #ddd;
            border-radius: 8px;
            font-family: "宋体", SimSun, serif;
            font-size: 16px;
            box-shadow: 0 2px 5px rgba(0,0,0,0.05);
            transition: border 0.3s;
        }
        
        input:focus, textarea:focus, select:focus {
            border-color: #3498db;
            outline: none;
        }
        
        textarea {
            height: 100px;
            resize: vertical;
        }
        
        .modal button[type="submit"] {
            width: 100%;
            padding: 14px;
            background: linear-gradient(to right, #3498db, #2c3e50);
            color: white;
            border: none;
            border-radius: 8px;
            font-family: "宋体", SimSun, serif;
            font-size: 16px;
            cursor: pointer;
            transition: all 0.3s;
            box-shadow: 0 4px 10px rgba(52, 152, 219, 0.3);
        }
        
        .modal button[type="submit"]:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 15px rgba(52, 152, 219, 0.4);
        }
        
        /* 响应式设计 */
        @media (max-width: 1400px) {
            .schools-container {
                grid-template-columns: repeat(4, 1fr);
            }
        }
        
        @media (max-width: 1200px) {
            .schools-container {
                grid-template-columns: repeat(3, 1fr);
            }
            
            .controls {
                flex-direction: column;
                align-items: flex-start;
                gap: 20px;
            }
            
            .left-controls {
                width: 100%;
                justify-content: space-between;
            }
        }
        
        @media (max-width: 900px) {
            .schools-container {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        
        @media (max-width: 600px) {
            .schools-container {
                grid-template-columns: 1fr;
            }
            
            .left-controls {
                flex-direction: column;
                align-items: flex-start;
                gap: 15px;
            }
            
            .stats-row {
                width: 100%;
                justify-content: space-between;
            }
        }
        
        .empty-state {
            text-align: center;
            padding: 40px 20px;
            color: #7f8c8d;
            grid-column: 1 / -1;
        }
        
        .empty-state i {
            font-size: 50px;
            margin-bottom: 15px;
            color: #bdc3c7;
        }