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

:root {
    --primary-color: #2481cc;
    --primary-dark: #1e6ba8;
    --secondary-color: #f0f4f8;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 100%;
    margin: 0 auto;
    padding: 0;
    min-height: 100vh;
    background: var(--bg-secondary);
}

/* Header */
.header {
    background: var(--bg-primary);
    padding: 16px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.header-title .icon {
    font-size: 28px;
}

.header-actions {
    display: flex;
    gap: 12px;
}

.btn-icon {
    background: var(--secondary-color);
    border: none;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 20px;
}

.btn-icon:hover {
    background: var(--border-color);
    transform: scale(1.05);
}

.btn-icon:active {
    transform: scale(0.95);
}

/* Filter Panel */
.filter-panel {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.filter-panel.active {
    max-height: 500px;
    padding: 20px;
}

.filter-content h3 {
    font-size: 18px;
    margin-bottom: 16px;
    color: var(--text-primary);
}

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

.filter-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.filter-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.chip {
    padding: 8px 16px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    border-radius: 20px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-secondary);
}

.chip:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.chip.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.filter-select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-primary);
    font-size: 14px;
    color: var(--text-primary);
}

.filter-actions {
    display: flex;
    gap: 12px;
    margin-top: 20px;
}

.btn-primary, .btn-secondary {
    flex: 1;
    padding: 12px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
}

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

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

/* Stats Bar */
.stats-bar {
    background: var(--bg-primary);
    padding: 16px 20px;
    display: flex;
    justify-content: space-around;
    gap: 16px;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 12px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.stat-value {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 12px;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Notifications Container */
.notifications-container {
    padding: 0 20px 20px;
}

.notification-item {
    background: var(--bg-primary);
    border-radius: var(--radius-md);
    padding: 16px;
    margin-bottom: 12px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    transition: all 0.2s;
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.notification-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.notification-item.unread {
    border-left: 4px solid var(--primary-color);
    background: linear-gradient(to right, rgba(36, 129, 204, 0.05), var(--bg-primary));
}

.notification-content {
    width: 100%;
}

.notification-header {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    margin-bottom: 12px;
}

.notification-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
}

.notification-icon.file_upload {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
}

.notification-icon.record_create {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
}

.notification-icon.record_update {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

.notification-icon.user_action {
    background: rgba(36, 129, 204, 0.1);
    color: var(--primary-color);
}

.notification-info {
    flex: 1;
    min-width: 0;
}

.notification-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.notification-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    color: var(--text-secondary);
}

.notification-user {
    font-weight: 500;
    color: var(--primary-color);
}

.notification-time {
    color: var(--text-light);
}

.notification-badge {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--primary-color);
    flex-shrink: 0;
    margin-top: 4px;
}

.notification-body {
    margin-top: 8px;
}

.notification-description {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 8px;
}

.notification-details {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 12px;
}

.notification-tag {
    padding: 4px 10px;
    background: var(--secondary-color);
    border-radius: 12px;
    font-size: 12px;
    color: var(--text-secondary);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    display: none;
}

.empty-state.active {
    display: block;
}

.empty-icon {
    font-size: 64px;
    margin-bottom: 16px;
    opacity: 0.5;
}

.empty-text {
    font-size: 16px;
    color: var(--text-secondary);
}

/* Loading State */
.loading-state {
    text-align: center;
    padding: 40px 20px;
    display: none;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    color: var(--text-secondary);
}

.loading-state.active {
    display: flex;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Time Group Separator */
.time-group {
    margin: 20px 0 12px;
    padding: 0 4px;
}

.time-group-title {
    font-size: 12px;
    font-weight: 600;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Responsive */
@media (max-width: 480px) {
    .header {
        padding: 12px 16px;
    }

    .header-title {
        font-size: 20px;
    }

    .notifications-container {
        padding: 0 16px 16px;
    }

    .notification-item {
        padding: 12px;
    }

    .stats-bar {
        padding: 12px 16px;
    }

    .stat-value {
        font-size: 20px;
    }
}