/* CSS Variables for consistent theming */
:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --light-gray: #f8f9fa;
    --dark-gray: #343a40;
    --border-radius: 8px;
    --box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

/* CSS Grid Layout System */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.layout-grid {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 20px;
    min-height: calc(100vh - 60px);
}

/* Modern Card Components */
.card {
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 20px;
    margin-bottom: 20px;
}

.card-header {
    font-weight: 600;
    font-size: 1.2rem;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid #eee;
}

/* Navigation */
.navigation {
    margin-bottom: 20px;
}

.nav-tabs {
    display: flex;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 5px;
}

.nav-tab {
    flex: 1;
    padding: 12px 20px;
    border: none;
    background: transparent;
    cursor: pointer;
    font-weight: 500;
    border-radius: var(--border-radius);
    transition: all 0.2s ease;
}

.nav-tab:hover {
    background-color: #f0f0f0;
}

.nav-tab.active {
    background-color: var(--primary-color);
    color: white;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, #0056b3 100%);
    color: white;
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,123,255,0.3);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn-success {
    background-color: var(--success-color);
    color: white;
}

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

.btn-warning {
    background-color: var(--warning-color);
    color: #212529;
}

.btn-large {
    padding: 15px 25px;
    font-size: 16px;
}

/* Icons */
.icon-sync::before {
    content: "↻";
    margin-right: 8px;
}

.icon-loading::before {
    content: "⏳";
    margin-right: 8px;
}

/* Status display */
.sync-status {
    margin-top: 15px;
    padding: 10px;
    border-radius: var(--border-radius);
    text-align: center;
    font-weight: 500;
}

.sync-status.syncing {
    background-color: #e3f2fd;
    color: var(--primary-color);
}

.sync-status.success {
    background-color: #e8f5e9;
    color: var(--success-color);
}

.sync-status.error {
    background-color: #ffebee;
    color: var(--danger-color);
}

/* Statistics */
.stat-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
    padding: 8px 0;
    border-bottom: 1px solid #eee;
}

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

.stat-item label {
    font-weight: 500;
    color: #666;
}

.stat-item span {
    font-weight: 600;
    color: #333;
}

/* Log display */
.log-content {
    max-height: 400px;
    overflow-y: auto;
    padding: 10px;
    background-color: #f8f9fa;
    border-radius: var(--border-radius);
    font-family: monospace;
    font-size: 0.9rem;
}

.log-entry {
    margin-bottom: 8px;
    padding: 8px;
    border-left: 3px solid #ddd;
    background-color: white;
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
}

.log-entry .timestamp {
    font-size: 0.8rem;
    color: #666;
    margin-right: 10px;
}

.log-entry .status {
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 500;
}

.log-entry .status.success {
    background-color: var(--success-color);
    color: white;
}

.log-entry .status.error {
    background-color: var(--danger-color);
    color: white;
}

/* Responsive Design */
@media (max-width: 768px) {
    .layout-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .sidebar {
        order: 2;
    }
    
    .main-content {
        order: 1;
    }
    
    .nav-tabs {
        flex-direction: column;
    }
    
    .container {
        padding: 0 10px;
    }
}