/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8fafc;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部导航 */
.header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 0;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 20px;
}

.nav-brand {
    display: flex;
    align-items: center;
    font-size: 24px;
    font-weight: bold;
    gap: 10px;
}

.brand-logo {
    width: 72px;
    height: 72px;
    object-fit: contain;
}

.beta-tag {
    background: rgba(255, 255, 255, 0.2);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 5px;
}

.nav-item {
    color: white;
    text-decoration: none;
    padding: 10px 16px;
    border-radius: 8px;
    transition: all 0.3s ease;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 8px;
    position: relative;
}

.nav-item:hover,
.nav-item.active {
    background-color: rgba(255, 255, 255, 0.15);
    transform: translateY(-1px);
}

.nav-item i {
    font-size: 16px;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 15px;
}

.action-btn {
    background: rgba(255, 255, 255, 0.1);
    border: none;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.action-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.05);
}

.action-btn .badge {
    position: absolute;
    top: -5px;
    right: -5px;
    background: #ff4757;
    color: white;
    border-radius: 50%;
    width: 18px;
    height: 18px;
    font-size: 11px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 12px;
    position: relative;
}

.user-details {
    display: flex;
    flex-direction: column;
    text-align: right;
}

.user-name {
    font-weight: 600;
    font-size: 14px;
}

.user-school {
    font-size: 12px;
    opacity: 0.8;
}

.user-avatar {
    width: 40px;
    height: 40px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.user-avatar:hover {
    background-color: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

.user-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    min-width: 200px;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    z-index: 1001;
    margin-top: 8px;
}

.user-menu.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    color: #333;
    text-decoration: none;
    transition: background-color 0.2s ease;
}

.menu-item:hover {
    background-color: #f8fafc;
}

.menu-divider {
    height: 1px;
    background-color: #e2e8f0;
    margin: 8px 0;
}

/* 主要内容区域 */
.main-content {
    min-height: calc(100vh - 64px);
    padding: 30px 0;
}

.page {
    display: none;
}

.page.active {
    display: block;
}

/* 欢迎区域 */
.welcome-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 16px;
    padding: 40px;
    margin-bottom: 30px;
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.welcome-content h1 {
    font-size: 32px;
    margin-bottom: 10px;
    font-weight: 600;
}

.welcome-content p {
    font-size: 16px;
    opacity: 0.9;
}

.quick-actions {
    display: flex;
    gap: 15px;
}

.quick-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 500;
    backdrop-filter: blur(10px);
}

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

/* 待办事项 */
.todo-section {
    margin-bottom: 40px;
}

.todo-section h2 {
    font-size: 24px;
    color: #2d3748;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.todo-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.todo-item {
    background: white;
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    display: flex;
    align-items: center;
    gap: 20px;
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
}

.todo-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.todo-item.urgent {
    border-left-color: #ff4757;
    background: linear-gradient(135deg, #fff5f5 0%, #ffffff 100%);
}

.todo-icon {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    color: white;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.todo-item.urgent .todo-icon {
    background: linear-gradient(135deg, #ff4757 0%, #ff3742 100%);
}

.todo-content {
    flex: 1;
}

.todo-content h4 {
    font-size: 18px;
    color: #2d3748;
    margin-bottom: 8px;
    font-weight: 600;
}

.todo-content p {
    color: #718096;
    margin-bottom: 8px;
    line-height: 1.5;
}

.todo-time {
    font-size: 14px;
    color: #a0aec0;
}

.todo-actions {
    display: flex;
    gap: 10px;
}

.btn-sm {
    padding: 8px 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-secondary {
    background: #e2e8f0;
    color: #4a5568;
}

.btn-sm:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* 功能区域 */
.feature-section {
    margin-bottom: 40px;
}

.feature-section h2 {
    font-size: 24px;
    color: #2d3748;
    margin-bottom: 30px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.feature-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 25px;
}

.card {
    background: white;
    border-radius: 16px;
    padding: 0;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    transition: all 0.3s ease;
    overflow: hidden;
    border: 1px solid #e2e8f0;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

.feature-card {
    cursor: pointer;
}

.card-header {
    padding: 24px 24px 16px;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.card-header .card-icon {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 20px;
    margin-bottom: 0;
}

.card-header h3 {
    font-size: 20px;
    color: #2d3748;
    margin: 8px 0;
    font-weight: 600;
}

.feature-badge {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    color: white;
    padding: 4px 12px;
    border-radius: 16px;
    font-size: 12px;
    font-weight: 500;
}

.feature-card p {
    padding: 0 24px;
    color: #718096;
    margin-bottom: 20px;
    line-height: 1.6;
}

.card-stats {
    padding: 0 24px 20px;
    display: flex;
    justify-content: space-between;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 20px;
    font-weight: bold;
    color: #2d3748;
}

.stat-label {
    font-size: 12px;
    color: #a0aec0;
    margin-top: 4px;
}

.card-actions {
    padding: 0 24px 24px;
}

.btn-card {
    width: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-card:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

/* 数据分析仪表板 */
.dashboard-analytics {
    margin-bottom: 40px;
}

.dashboard-analytics h2 {
    font-size: 24px;
    color: #2d3748;
    margin-bottom: 30px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.analytics-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.analytics-card {
    background: white;
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.analytics-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
}

.analytics-header h3 {
    font-size: 18px;
    color: #2d3748;
    font-weight: 600;
}

.period-selector select {
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    padding: 8px 12px;
    font-size: 14px;
    color: #4a5568;
    background: white;
}

.metric-row {
    display: flex;
    gap: 24px;
    margin-bottom: 24px;
}

.metric-row:last-child {
    margin-bottom: 0;
}

.metric {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px;
    background: #f8fafc;
    border-radius: 12px;
}

.metric-icon {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.metric-data {
    flex: 1;
}

.metric-number {
    display: block;
    font-size: 20px;
    font-weight: bold;
    color: #2d3748;
}

.metric-label {
    font-size: 14px;
    color: #718096;
}

.metric-trend {
    font-size: 12px;
    font-weight: 500;
    padding: 2px 8px;
    border-radius: 12px;
    margin-top: 4px;
    display: inline-block;
}

.metric-trend.up {
    background: #d4f4dd;
    color: #22543d;
}

.metric-trend.down {
    background: #fed7d7;
    color: #822727;
}

.metric-trend.stable {
    background: #e2e8f0;
    color: #4a5568;
}

.chart-container {
    height: 150px;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #f8fafc;
    border-radius: 8px;
}

.chart-legend {
    display: flex;
    justify-content: center;
    gap: 20px;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: #718096;
}

.legend-color {
    width: 12px;
    height: 12px;
    border-radius: 2px;
}

/* 最近活动优化 */
.recent-activities {
    margin-bottom: 40px;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
}

.section-header h2 {
    font-size: 24px;
    color: #2d3748;
    display: flex;
    align-items: center;
    gap: 10px;
}

.view-all {
    color: #667eea;
    text-decoration: none;
    font-weight: 500;
    font-size: 14px;
}

.view-all:hover {
    text-decoration: underline;
}

.activity-timeline {
    background: white;
    border-radius: 16px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    overflow: hidden;
}

.activity-item {
    display: flex;
    padding: 24px;
    border-bottom: 1px solid #f7fafc;
    position: relative;
}

.activity-item:last-child {
    border-bottom: none;
}

.activity-time {
    min-width: 80px;
    font-size: 14px;
    color: #a0aec0;
    padding-top: 4px;
}

.activity-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    margin: 0 20px;
    font-size: 16px;
}

.activity-icon.success {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
}

.activity-icon.info {
    background: linear-gradient(135deg, #4299e1 0%, #3182ce 100%);
}

.activity-icon.warning {
    background: linear-gradient(135deg, #ed8936 0%, #dd6b20 100%);
}

.activity-content {
    flex: 1;
}

.activity-title {
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 8px;
}

.activity-details {
    color: #718096;
    font-size: 14px;
    margin-bottom: 12px;
    line-height: 1.5;
}

.activity-meta {
    display: flex;
    gap: 8px;
}

.tag {
    background: #e2e8f0;
    color: #4a5568;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

/* 通知面板 */
.notification-panel {
    position: fixed;
    top: 70px;
    right: 20px;
    width: 400px;
    background: white;
    border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
    z-index: 1002;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-20px);
    transition: all 0.3s ease;
    max-height: 500px;
    overflow: hidden;
}

.notification-panel.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.notification-header {
    padding: 20px 24px;
    border-bottom: 1px solid #e2e8f0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.notification-header h3 {
    font-size: 18px;
    color: #2d3748;
    font-weight: 600;
}

.close-btn {
    background: none;
    border: none;
    color: #a0aec0;
    cursor: pointer;
    padding: 4px;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.close-btn:hover {
    color: #718096;
    background: #f7fafc;
}

.notification-list {
    max-height: 400px;
    overflow-y: auto;
}

.notification-item {
    display: flex;
    padding: 20px 24px;
    border-bottom: 1px solid #f7fafc;
    transition: background-color 0.2s ease;
}

.notification-item:hover {
    background: #f8fafc;
}

.notification-item:last-child {
    border-bottom: none;
}

.notification-item.unread {
    position: relative;
}

.notification-item.unread::before {
    content: '';
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    width: 6px;
    height: 6px;
    background: #667eea;
    border-radius: 50%;
}

.notification-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    margin-right: 16px;
    font-size: 16px;
}

.notification-content {
    flex: 1;
}

.notification-content h4 {
    font-size: 14px;
    color: #2d3748;
    font-weight: 600;
    margin-bottom: 4px;
}

.notification-content p {
    font-size: 13px;
    color: #718096;
    line-height: 1.4;
    margin-bottom: 8px;
}

.notification-time {
    font-size: 12px;
    color: #a0aec0;
}

/* 按钮样式 */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.btn-secondary {
    background: #e2e8f0;
    color: #4a5568;
}

.btn-secondary:hover {
    background: #cbd5e0;
}

.btn-success {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

.btn-success:hover {
    opacity: 0.9;
}

/* 表单样式 */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #2d3748;
}

.form-control {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 14px;
    transition: border-color 0.3s ease;
    background: white;
}

.form-control:focus {
    outline: none;
    border-color: #667eea;
}

.form-select {
    background-image: url("data:image/svg+xml;charset=UTF-8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'><polyline points='6,9 12,15 18,9'></polyline></svg>");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 16px;
    appearance: none;
}

/* 消息提示 Toast */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 16px 20px;
    border-radius: 12px;
    color: white;
    font-weight: 500;
    z-index: 10001;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
    max-width: 400px;
    backdrop-filter: blur(10px);
}

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

.toast.success {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
}

.toast.error {
    background: linear-gradient(135deg, #f56565 0%, #e53e3e 100%);
}

.toast.warning {
    background: linear-gradient(135deg, #ed8936 0%, #dd6b20 100%);
}

.toast.info {
    background: linear-gradient(135deg, #4299e1 0%, #3182ce 100%);
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .analytics-grid {
        grid-template-columns: 1fr;
    }
    
    .feature-cards {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
}

@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 15px;
        padding: 15px 20px;
    }
    
    .nav-menu {
        flex-wrap: wrap;
        gap: 10px;
    }
    
    .nav-item {
        padding: 8px 12px;
        font-size: 14px;
    }
    
    .nav-item span {
        display: none;
    }
    
    .welcome-section {
        flex-direction: column;
        text-align: center;
        gap: 20px;
    }
    
    .quick-actions {
        justify-content: center;
    }
    
    .feature-cards {
        grid-template-columns: 1fr;
    }
    
    .todo-item {
        flex-direction: column;
        text-align: center;
        gap: 16px;
    }
    
    .todo-actions {
        justify-content: center;
    }
    
    .metric-row {
        flex-direction: column;
        gap: 16px;
    }
    
    .activity-item {
        flex-direction: column;
        gap: 16px;
    }
    
    .activity-time {
        text-align: center;
        min-width: auto;
    }
    
    .activity-icon {
        margin: 0 auto;
    }
    
    .notification-panel {
        width: calc(100% - 40px);
        right: 20px;
        left: 20px;
    }
    
    .container {
        padding: 0 15px;
    }
    
    .main-content {
        padding: 20px 0;
    }
}

@media (max-width: 480px) {
    .welcome-section {
        padding: 24px 20px;
    }
    
    .welcome-content h1 {
        font-size: 24px;
    }
    
    .feature-section h2,
    .dashboard-analytics h2,
    .todo-section h2,
    .section-header h2 {
        font-size: 20px;
    }
    
    .card {
        margin: 0 -10px;
    }
    
    .analytics-card {
        padding: 20px;
    }
    
    .activity-timeline {
        margin: 0 -10px;
    }
    
    .notification-panel {
        width: calc(100% - 20px);
        right: 10px;
        left: 10px;
        top: 80px;
    }
}

/* 工具样式类 */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 0.75rem; }
.mt-4 { margin-top: 1rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 0.75rem; }
.mb-4 { margin-bottom: 1rem; }

.hidden { display: none; }
.block { display: block; }
.flex { display: flex; }
.inline-flex { display: inline-flex; }

.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }