:root {
    --primary-color: #2c3e50;
    --accent-color: #3498db;
    --danger-color: #e74c3c;
    --success-color: #2ecc71;
    --warning-color: #f39c12;
    --text-color: #333333;
    --light-bg: #f8f9fa;
    --medium-gray: #e9ecef;
    --dark-gray: #dee2e6;
    --white: #ffffff;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --transition-speed: 0.2s;
    --sidebar-width: 240px;
    --header-height: 60px;
}

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

body {
    font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--light-bg);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    min-height: 100vh;
}

/* 头部导航栏 */
.header {
    background-color: var(--white);
    height: var(--header-height);
    width: 100%;
    position: fixed;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    box-shadow: var(--shadow-md);
}

.logo-container {
    display: flex;
    align-items: center;
}

.logo {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    text-decoration: none;
    margin-right: 10px;
    display: flex;
    align-items: center;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.notification-icon {
    color: var(--text-color);
    font-size: 1.1rem;
    position: relative;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    transition: all var(--transition-speed) ease;
}

.notification-icon:hover {
    background-color: var(--medium-gray);
}

.notification-badge {
    position: absolute;
    top: -5px;
    right: -5px;
    background-color: var(--danger-color);
    color: var(--white);
    font-size: 0.7rem;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.user-info-container {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 12px;
    border-radius: 20px;
    transition: all var(--transition-speed) ease;
}

.user-info-container:hover {
    background-color: var(--medium-gray);
}

.user-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background-color: var(--accent-color);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-weight: bold;
    font-size: 1rem;
}

.user-name {
    font-size: 0.9rem;
    white-space: nowrap;
    max-width: 150px;
    overflow: hidden;
    text-overflow: ellipsis;
}

.logout-btn {
    background-color: transparent;
    color: var(--text-color);
    border: none;
    padding: 6px 12px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all var(--transition-speed) ease;
    margin-left: 10px;
}

.logout-btn:hover {
    background-color: var(--danger-color);
    color: var(--white);
}

/* 左侧菜单栏 */
.sidebar {
    background-color: var(--white);
    width: var(--sidebar-width);
    height: calc(100vh - var(--header-height));
    position: fixed;
    top: var(--header-height);
    left: 0;
    z-index: 90;
    overflow-y: auto;
    border-right: 1px solid var(--medium-gray);
    transition: width 0.3s ease;
}

.sidebar-header {
    padding: 16px 20px;
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--medium-gray);
    background-color: var(--primary-color);
    color: white;
}

.sidebar-title {
    font-size: 1.1rem;
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.menu-items {
    padding: 15px 0;
}

.menu-item {
    padding: 12px 20px;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    display: flex;
    align-items: center;
    position: relative;
    margin: 8px 10px;
    border-radius: 8px;
    color: var(--text-color);
    -webkit-user-drag: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    border: 1px solid rgba(0, 0, 0, 0.05);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    background-color: var(--white);
}

.menu-item:hover {
    background-color: rgba(52, 152, 219, 0.1);
    color: var(--accent-color);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    border-color: rgba(0, 0, 0, 0.1);
}

.menu-item.active {
    background-color: var(--accent-color);
    color: var(--white);
    box-shadow: 0 4px 12px rgba(52, 152, 219, 0.3);
    border-color: var(--accent-color);
}

.menu-item-icon {
    margin-right: 12px;
    font-size: 1.1rem;
    min-width: 24px;
    display: flex;
    justify-content: center;
}

.menu-item-text {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.menu-item.has-submenu {
    position: relative;
    padding-right: 35px;
}

.menu-item.has-submenu::after {
    content: '🛆';
    position: absolute;
    right: 15px;
    font-size: 0.7rem;
    transition: transform var(--transition-speed) ease;
    transform: rotate(180deg);
    transform-origin: center center;
    will-change: transform;
}

.menu-item.has-submenu.expanded::after {
    transform: rotate(0deg);
}

.submenu-container {
    width: calc(100% - 20px);
    margin-left: 10px;
    background-color: rgba(233, 236, 239, 0.3);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    border-radius: 6px;
    margin-top: 0;
    margin-bottom: 0;
}

.submenu-container.expanded {
    max-height: 500px;
}

.submenu-item {
    padding: 8px 15px 8px 35px;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    display: flex;
    align-items: center;
    font-size: 0.95rem;
    color: var(--text-color);
    -webkit-user-drag: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    position: relative;
    border: 1px solid rgba(0, 0, 0, 0.03);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
    margin: 2px 0;
    background-color: var(--white);
    border-radius: 6px;
}

.submenu-item:hover {
    color: var(--accent-color);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
    border-color: rgba(0, 0, 0, 0.08);
}

.submenu-item.active {
    color: var(--accent-color);
    font-weight: 500;
    box-shadow: 0 2px 8px rgba(52, 152, 219, 0.2);
    border-color: rgba(52, 152, 219, 0.3);
}

.submenu-item.active::before {
    content: '';
    position: absolute;
    left: 20px;
    top: 50%;
    transform: translateY(-50%);
    width: 6px;
    height: 6px;
    background-color: var(--accent-color);
    border-radius: 50%;
}

.menu-divider {
    height: 1px;
    background-color: var(--medium-gray);
    margin: 15px 20px;
    position: relative;
}

.menu-divider::after {
    content: attr(data-label);
    position: absolute;
    left: 20px;
    top: 50%;
    transform: translateY(-50%);
    background-color: var(--white);
    padding: 0 10px;
    font-size: 0.75rem;
    color: var(--text-color);
    opacity: 0.7;
}

/* 主内容区域 */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    margin-top: var(--header-height);
    padding: 20px;
    background-color: var(--light-bg);
    overflow-y: auto;
    min-height: calc(100vh - var(--header-height));
}

.content-section {
    background-color: var(--white);
    border-radius: 12px;
    padding: 20px;
    box-shadow: var(--shadow-md);
    margin-bottom: 20px;
}

.section-title {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.2rem;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--medium-gray);
    font-weight: 500;
}

.content-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 15px;
    margin-top: 15px;
}

.content-card {
    background: linear-gradient(135deg, #f8f9fa, #e9ecef);
    border-radius: 10px;
    padding: 16px;
    transition: all var(--transition-speed) ease;
    border: 1px solid var(--medium-gray);
}

.content-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
    border-color: var(--dark-gray);
}

.card-title {
    font-weight: 500;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    color: var(--primary-color);
}

.card-icon {
    margin-right: 8px;
    font-size: 1.1rem;
}

.card-value {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: 10px 0;
}

.card-footer {
    display: flex;
    justify-content: space-between;
    color: var(--text-color);
    font-size: 0.85rem;
    margin-top: 10px;
    padding-top: 8px;
    border-top: 1px solid var(--medium-gray);
}

.todo-list {
    margin-top: 15px;
}

.todo-item {
    display: flex;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--medium-gray);
}

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

.todo-number {
    width: 28px;
    height: 28px;
    background-color: var(--accent-color);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 15px;
    font-size: 0.9rem;
    font-weight: 500;
}

.todo-content {
    flex: 1;
}

.todo-title {
    font-weight: 500;
    margin-bottom: 4px;
}

.todo-description {
    font-size: 0.85rem;
    color: var(--text-color);
    opacity: 0.7;
}

.todo-due {
    font-size: 0.85rem;
    padding: 4px 8px;
    border-radius: 12px;
    font-weight: 500;
}

.todo-due.today {
    background-color: var(--danger-color);
    color: var(--white);
}

.todo-due.soon {
    background-color: var(--warning-color);
    color: var(--white);
}

.todo-due.upcoming {
    background-color: var(--success-color);
    color: var(--white);
}

@media (max-width: 1024px) {
    .menu-item {
        margin: 6px 5px;
    }

    .submenu-item {
        margin: 1px 0;
    }
}

@media (max-width: 768px) {
    .header {
        padding: 0 10px;
    }

    .main-content {
        padding: 15px;
    }

    .content-grid {
        grid-template-columns: 1fr;
    }
}

.page-item {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    border: 1px solid var(--medium-gray);
    background-color: var(--white);
    cursor: pointer;
    transition: all var(--transition-speed) ease;
}

.page-item1 {
    width: 50px;
}

.page-item.active {
    background-color: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.page-item:hover:not(.active) {
    background-color: rgba(52, 152, 219, 0.1);
}