* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

header {
    text-align: center;
    color: white;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 15px;
}

.user-info {
    background: rgba(255, 255, 255, 0.2);
    padding: 10px 20px;
    border-radius: 20px;
    display: inline-block;
    font-size: 14px;
}

.user-info button {
    background: rgba(255, 255, 255, 0.3);
    border: none;
    color: white;
    padding: 5px 15px;
    border-radius: 15px;
    cursor: pointer;
    margin-left: 10px;
    transition: background 0.3s;
}

.user-info button:hover {
    background: rgba(255, 255, 255, 0.5);
}

.nav-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    justify-content: center;
}

.tab-btn {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: none;
    padding: 12px 25px;
    border-radius: 25px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s;
}

.tab-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.tab-btn.active {
    background: white;
    color: #667eea;
    font-weight: 600;
}

.main-content {
    background: white;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    min-height: 600px;
    display: none;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.form-section,
.list-section,
.leaderboard-section,
.admin-section {
    max-width: 800px;
    margin: 0 auto;
}

.form-section h2,
.list-section h2,
.leaderboard-section h2,
.admin-section h2 {
    color: #333;
    margin-bottom: 25px;
    font-size: 1.5rem;
    border-bottom: 2px solid #667eea;
    padding-bottom: 10px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 6px;
    font-size: 14px;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
}

.form-group textarea {
    resize: vertical;
}

.btn-submit {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-submit:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.vulnerability-list {
    max-height: 600px;
    overflow-y: auto;
}

.vulnerability-card {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 15px;
    border-left: 4px solid #667eea;
    transition: transform 0.2s;
}

.vulnerability-card:hover {
    transform: translateX(5px);
}

.vulnerability-card.severity-低 {
    border-left-color: #28a745;
}

.vulnerability-card.severity-中 {
    border-left-color: #ffc107;
}

.vulnerability-card.severity-高 {
    border-left-color: #fd7e14;
}

.vulnerability-card.severity-严重 {
    border-left-color: #dc3545;
}

.vulnerability-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.vulnerability-title {
    font-weight: 600;
    color: #333;
    font-size: 1.1rem;
}

.vulnerability-severity {
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    color: white;
}

.severity-低 .vulnerability-severity {
    background: #28a745;
}

.severity-中 .vulnerability-severity {
    background: #ffc107;
}

.severity-高 .vulnerability-severity {
    background: #fd7e14;
}

.severity-严重 .vulnerability-severity {
    background: #dc3545;
}

.vulnerability-description {
    color: #666;
    margin-bottom: 10px;
    line-height: 1.5;
}

.vulnerability-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    color: #999;
}

.vulnerability-status {
    padding: 3px 10px;
    border-radius: 15px;
    font-size: 11px;
    font-weight: 600;
}

.status-待审核 {
    background: #e9ecef;
    color: #495057;
}

.status-已通过 {
    background: #d4edda;
    color: #155724;
}

.status-已拒绝 {
    background: #f8d7da;
    color: #721c24;
}

.vulnerability-points {
    background: #007bff;
    color: white;
    padding: 3px 10px;
    border-radius: 15px;
    font-size: 11px;
    font-weight: 600;
}

.vulnerability-actions {
    margin-top: 10px;
    display: flex;
    gap: 10px;
}

.btn-action {
    padding: 5px 10px;
    border: none;
    border-radius: 4px;
    font-size: 12px;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-approve {
    background: #28a745;
    color: white;
}

.btn-approve:hover {
    background: #218838;
}

.btn-reject {
    background: #dc3545;
    color: white;
}

.btn-reject:hover {
    background: #c82333;
}

.loading {
    text-align: center;
    color: #999;
    padding: 20px;
}

.leaderboard {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 20px;
}

.leaderboard-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px;
    background: white;
    border-radius: 6px;
    margin-bottom: 10px;
    transition: transform 0.2s;
}

.leaderboard-item:hover {
    transform: translateX(5px);
}

.leaderboard-item.rank-1 {
    border-left: 4px solid #ffd700;
    background: linear-gradient(to right, #fff9db, white);
}

.leaderboard-item.rank-2 {
    border-left: 4px solid #c0c0c0;
    background: linear-gradient(to right, #f8f9fa, white);
}

.leaderboard-item.rank-3 {
    border-left: 4px solid #cd7f32;
    background: linear-gradient(to right, #f5f0e8, white);
}

.leaderboard-rank {
    font-size: 24px;
    font-weight: 700;
    width: 50px;
    text-align: center;
}

.leaderboard-rank.rank-1 {
    color: #ffd700;
}

.leaderboard-rank.rank-2 {
    color: #c0c0c0;
}

.leaderboard-rank.rank-3 {
    color: #cd7f32;
}

.leaderboard-info {
    flex: 1;
    padding: 0 20px;
}

.leaderboard-name {
    font-weight: 600;
    color: #333;
    margin-bottom: 5px;
}

.leaderboard-team {
    font-size: 12px;
    color: #999;
}

.leaderboard-score {
    font-size: 24px;
    font-weight: 700;
    color: #667eea;
}

.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    border-radius: 8px;
    color: white;
    font-weight: 500;
    transform: translateX(400px);
    transition: transform 0.3s ease;
    z-index: 1000;
}

.notification.show {
    transform: translateX(0);
}

.notification.success {
    background: #28a745;
}

.notification.error {
    background: #dc3545;
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    .nav-tabs {
        flex-wrap: wrap;
    }

    .tab-btn {
        padding: 10px 15px;
        font-size: 12px;
    }

    .main-content {
        padding: 20px;
    }
}