:root {
    --primary-color: #0d6efd;
    --secondary-color: #6c757d;
    --success-color: #198754;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --info-color: #0dcaf0;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --sidebar-width: 250px;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f8f9fa;
}

/* Sidebar Styles */
#sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    z-index: 100;
    padding: 48px 0 0;
    box-shadow: inset -1px 0 0 rgba(0, 0, 0, .1);
}

#sidebar .nav-link {
    font-weight: 500;
    color: #333;
    padding: 12px 20px;
    border-radius: 8px;
    margin: 2px 10px;
    transition: all 0.3s ease;
}

#sidebar .nav-link:hover {
    background-color: #e9ecef;
    color: var(--primary-color);
}

#sidebar .nav-link.active {
    background-color: var(--primary-color);
    color: white;
}

/* Main Content */
main {
    margin-left: var(--sidebar-width);
    padding-top: 20px;
}

/* Card Styles */
.card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    transition: all 0.3s ease;
}

.card:hover {
    box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

.card-header {
    background-color: transparent;
    border-bottom: 1px solid #dee2e6;
    font-weight: 600;
    padding: 1.25rem;
}

/* Stats Cards */
.stats-card {
    background: linear-gradient(135deg, var(--primary-color), #0056b3);
    color: white;
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 20px;
}

.stats-card.success {
    background: linear-gradient(135deg, var(--success-color), #146c43);
}

.stats-card.warning {
    background: linear-gradient(135deg, var(--warning-color), #cc9a00);
}

.stats-card.danger {
    background: linear-gradient(135deg, var(--danger-color), #b02a37);
}

.stats-card.info {
    background: linear-gradient(135deg, var(--info-color), #0aa2c0);
}

.stats-number {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 5px;
}

.stats-label {
    font-size: 0.9rem;
    opacity: 0.9;
}

/* Task Status Badges */
.task-status {
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.task-status.new {
    background-color: #e3f2fd;
    color: #1976d2;
}

.task-status.in-progress {
    background-color: #fff3e0;
    color: #f57c00;
}

.task-status.completed {
    background-color: #e8f5e8;
    color: #388e3c;
}

.task-status.on-hold {
    background-color: #fce4ec;
    color: #c2185b;
}

/* Priority Badges */
.priority-badge {
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.7rem;
    font-weight: 600;
}

.priority-badge.low {
    background-color: #e8f5e8;
    color: #2e7d32;
}

.priority-badge.medium {
    background-color: #fff3e0;
    color: #f57c00;
}

.priority-badge.high {
    background-color: #ffebee;
    color: #d32f2f;
}

.priority-badge.urgent {
    background-color: #f3e5f5;
    color: #7b1fa2;
}

/* Progress Bars */
.progress {
    height: 8px;
    border-radius: 10px;
    background-color: #e9ecef;
}

.progress-bar {
    border-radius: 10px;
    transition: width 0.6s ease;
}

/* Kanban Board */
.kanban-board {
    display: flex;
    gap: 20px;
    overflow-x: auto;
    padding: 20px 0;
}

.kanban-column {
    min-width: 300px;
    background-color: #f8f9fa;
    border-radius: 12px;
    padding: 15px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.kanban-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid #dee2e6;
}

.kanban-title {
    font-weight: 600;
    font-size: 1.1rem;
}

.kanban-count {
    background-color: var(--primary-color);
    color: white;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
}

.kanban-card {
    background-color: white;
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    cursor: pointer;
    transition: all 0.3s ease;
}

.kanban-card:hover {
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
    transform: translateY(-2px);
}

/* Forms */
.form-control {
    border-radius: 8px;
    border: 1px solid #dee2e6;
    padding: 10px 15px;
    transition: all 0.3s ease;
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(13, 110, 253, 0.25);
}

.btn {
    border-radius: 8px;
    padding: 10px 20px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), #0056b3);
    border: none;
}

.btn-primary:hover {
    background: linear-gradient(135deg, #0056b3, #004085);
}

/* Tables */
.table {
    border-collapse: separate;
    border-spacing: 0;
}

.table th {
    background-color: #f8f9fa;
    border-bottom: 2px solid #dee2e6;
    font-weight: 600;
    padding: 15px;
}

.table td {
    padding: 12px 15px;
    vertical-align: middle;
}

.table tbody tr {
    transition: all 0.3s ease;
}

.table tbody tr:hover {
    background-color: #f8f9fa;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

/* Modal Styles */
.modal-content {
    border-radius: 15px;
    border: none;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.modal-header {
    border-bottom: 1px solid #dee2e6;
    border-radius: 15px 15px 0 0;
}

.modal-footer {
    border-top: 1px solid #dee2e6;
    border-radius: 0 0 15px 15px;
}

/* AI Insights */
.ai-insight-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 20px;
}

.ai-insight-card .card-title {
    color: white;
    font-weight: 600;
}

.ai-confidence {
    background-color: rgba(255, 255, 255, 0.2);
    padding: 5px 10px;
    border-radius: 15px;
    font-size: 0.8rem;
    display: inline-block;
}

/* Notification Styles */
.notification-dropdown {
    border: none;
    box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
}

.notification-item {
    border-bottom: 1px solid #dee2e6;
    cursor: pointer;
    transition: background-color 0.2s;
}

.notification-item:hover {
    background-color: #f8f9fa;
}

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

.notification-item .dropdown-header {
    font-size: 0.875rem;
    font-weight: 600;
    color: #495057;
}

.notification-item p {
    color: #6c757d;
    line-height: 1.4;
}

#notification-count {
    font-size: 0.75rem;
    min-width: 18px;
    height: 18px;
    line-height: 18px;
}

/* Responsive Design */
@media (max-width: 768px) {
    #sidebar {
        margin-left: -250px;
    }
    
    main {
        margin-left: 0;
    }
    
    .kanban-board {
        flex-direction: column;
    }
    
    .kanban-column {
        min-width: 100%;
    }
    
    .stats-number {
        font-size: 2rem;
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}

/* Animation Classes */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.slide-in-right {
    animation: slideInRight 0.5s ease-out;
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(30px); }
    to { opacity: 1; transform: translateX(0); }
}

/* Chart Container */
.chart-container {
    position: relative;
    height: 400px;
    margin: 20px 0;
}

/* Timeline Styles */
.timeline {
    position: relative;
    padding: 20px 0;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    width: 2px;
    height: 100%;
    background: var(--primary-color);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin: 20px 0;
    padding: 20px;
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    width: 45%;
}

.timeline-item:nth-child(odd) {
    margin-left: 0;
}

.timeline-item:nth-child(even) {
    margin-left: 55%;
}

.timeline-item::before {
    content: '';
    position: absolute;
    top: 20px;
    width: 15px;
    height: 15px;
    background: var(--primary-color);
    border-radius: 50%;
}

.timeline-item:nth-child(odd)::before {
    right: -7px;
}

.timeline-item:nth-child(even)::before {
    left: -7px;
}