body { 
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
        background-color: #f9fafb;
    }
    
    /* Mobile Menu Button */
    .mobile-menu-btn {
        display: none;
        position: fixed;
        top: 16px;
        left: 16px;
        z-index: 50;
        background: white;
        padding: 8px;
        border-radius: 8px;
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
        border: none;
        cursor: pointer;
        transition: all 0.2s;
    }
    
    .mobile-menu-btn:hover {
        background: #f3f4f6;
    }
    
    .mobile-menu-btn svg {
        width: 24px;
        height: 24px;
        color: #374151;
    }
    
    /* Sidebar */
    .sidebar {
        width: 280px;
        background: white;
        height: 100vh;
        position: fixed;
        left: 0;
        top: 0;
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
        z-index: 40;
        transition: transform 0.3s ease;
        overflow-y: auto;
    }
    
    .sidebar.closed {
        transform: translateX(-100%);
    }
    
    .sidebar-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: 35;
    }
    
    .sidebar-overlay.active {
        display: block;
    }
    
    .main-content {
        margin-left: 280px;
        min-height: 100vh;
        padding: 24px;
        transition: margin-left 0.3s ease;
    }
    
    .main-content.expanded {
        margin-left: 0;
    }
    
    .logo-section {
        padding: 24px;
        border-bottom: 1px solid #e5e7eb;
        position: relative;
    }
    
    .sidebar-close {
        display: none;
        position: absolute;
        top: 24px;
        right: 24px;
        background: none;
        border: none;
        cursor: pointer;
        padding: 4px;
        border-radius: 4px;
        color: #6b7280;
    }
    
    .sidebar-close:hover {
        background: #f3f4f6;
        color: #374151;
    }
    
    .logo {
        font-size: 1.5rem;
        font-weight: bold;
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
    }
    
    .nav-section {
        padding: 24px 0 120px 0;
    }
    
    .nav-item {
        display: flex;
        align-items: center;
        padding: 12px 24px;
        color: #6b7280;
        text-decoration: none;
        transition: all 0.2s;
        margin: 0 16px;
        border-radius: 8px;
        position: relative;
    }
    
    .nav-item:hover {
        background-color: #f3f4f6;
        color: #374151;
    }
    
    .nav-item.active {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        color: white;
    }
    
    .nav-item svg {
        width: 20px;
        height: 20px;
        margin-right: 12px;
        flex-shrink: 0;
    }
    
    .upgrade-section {
        position: fixed;
        bottom: 24px;
        left: 16px;
        width: 248px;
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        border-radius: 12px;
        padding: 16px;
        text-align: center;
    }
    
    .upgrade-section h3 {
        color: white;
        font-size: 0.875rem;
        font-weight: 600;
        margin: 0 0 8px 0;
    }
    
    .upgrade-section p {
        color: rgba(219, 234, 254, 0.8);
        font-size: 0.75rem;
        margin: 0 0 12px 0;
    }
    
    .upgrade-btn {
        background: white;
        color: #667eea;
        padding: 8px 16px;
        border-radius: 6px;
        font-size: 0.75rem;
        font-weight: 600;
        text-decoration: none;
        display: inline-block;
    }
    
    .upgrade-btn:hover {
        transform: translateY(-1px);
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    }
    
    /* Settings Page Header */
    .settings-header {
        background: white;
        border-radius: 12px;
        padding: 24px;
        margin-bottom: 24px;
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
        display: flex;
        justify-content: space-between;
        align-items: center;
        flex-wrap: wrap;
        gap: 16px;
    }
    
    .settings-title {
        display: flex;
        align-items: center;
        gap: 16px;
    }
    
    .settings-title h1 {
        font-size: 1.875rem;
        font-weight: bold;
        color: #111827;
        margin: 0;
    }
    
    .starter-badge {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        color: white;
        padding: 4px 12px;
        border-radius: 20px;
        font-size: 0.75rem;
        font-weight: 600;
    }
    
    .settings-actions {
        display: flex;
        gap: 12px;
        flex-wrap: wrap;
        align-items: center;
    }
    
    .save-all-btn {
        background: #667eea;
        color: white;
        padding: 10px 20px;
        border-radius: 8px;
        text-decoration: none;
        font-size: 0.875rem;
        font-weight: 500;
        transition: all 0.2s;
        display: flex;
        align-items: center;
        gap: 8px;
        border: none;
        cursor: pointer;
    }
    
    .save-all-btn:hover {
        background: #5b21b6;
        transform: translateY(-1px);
    }
    
    .last-saved {
        background: #f3f4f6;
        padding: 8px 16px;
        border-radius: 8px;
        font-size: 0.875rem;
        color: #6b7280;
        display: flex;
        align-items: center;
        gap: 8px;
    }
    
    /* Settings Navigation */
    .settings-nav {
        background: white;
        border-radius: 12px;
        padding: 20px;
        margin-bottom: 24px;
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    }
    
    .settings-tabs {
        display: flex;
        gap: 8px;
        flex-wrap: wrap;
        border-bottom: 1px solid #e5e7eb;
        padding-bottom: 16px;
    }
    
    .settings-tab {
        padding: 8px 16px;
        border-radius: 6px;
        font-size: 0.875rem;
        font-weight: 500;
        border: none;
        background: transparent;
        color: #6b7280;
        text-decoration: none;
        transition: all 0.2s;
        cursor: pointer;
        display: flex;
        align-items: center;
        gap: 8px;
    }
    
    .settings-tab.active {
        background: #667eea;
        color: white;
    }
    
    .settings-tab:hover:not(.active) {
        background: #f3f4f6;
        color: #374151;
    }
    
    /* Settings Content */
    .settings-content {
        display: grid;
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .settings-section {
        background: white;
        border-radius: 12px;
        padding: 24px;
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
        display: none;
    }
    
    .settings-section.active {
        display: block;
    }
    
    .section-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        margin-bottom: 24px;
        padding-bottom: 16px;
        border-bottom: 1px solid #e5e7eb;
    }
    
    .section-title {
        font-size: 1.25rem;
        font-weight: 600;
        color: #111827;
        margin: 0;
        display: flex;
        align-items: center;
        gap: 8px;
    }
    
    .section-save-btn {
        background: #667eea;
        color: white;
        border: none;
        padding: 8px 16px;
        border-radius: 6px;
        font-size: 0.875rem;
        font-weight: 500;
        cursor: pointer;
        transition: all 0.2s;
    }
    
    .section-save-btn:hover {
        background: #5b21b6;
    }
    
    /* Form Elements */
    .form-group {
        margin-bottom: 24px;
    }
    
    .form-label {
        display: block;
        font-weight: 500;
        color: #374151;
        margin-bottom: 6px;
        font-size: 0.875rem;
    }
    
    .form-description {
        font-size: 0.75rem;
        color: #6b7280;
        margin-bottom: 8px;
        line-height: 1.4;
    }
    
    .form-input {
        width: 100%;
        padding: 10px 12px;
        border: 1px solid #e5e7eb;
        border-radius: 6px;
        font-size: 0.875rem;
        transition: all 0.2s;
    }
    
    .form-input:focus {
        outline: none;
        border-color: #667eea;
        box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
    }
    
    .form-row {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }
    
    .form-textarea {
        min-height: 80px;
        resize: vertical;
    }
    
    /* Toggle Switch */
    .toggle-switch {
        position: relative;
        display: inline-block;
        width: 48px;
        height: 24px;
    }
    
    .toggle-switch input {
        opacity: 0;
        width: 0;
        height: 0;
    }
    
    .toggle-slider {
        position: absolute;
        cursor: pointer;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background-color: #d1d5db;
        transition: 0.3s;
        border-radius: 24px;
    }
    
    .toggle-slider:before {
        position: absolute;
        content: "";
        height: 20px;
        width: 20px;
        left: 2px;
        bottom: 2px;
        background-color: white;
        transition: 0.3s;
        border-radius: 50%;
    }
    
    input:checked + .toggle-slider {
        background-color: #667eea;
    }
    
    input:checked + .toggle-slider:before {
        transform: translateX(24px);
    }
    
    .toggle-group {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 16px;
        border: 1px solid #e5e7eb;
        border-radius: 8px;
        margin-bottom: 12px;
        transition: all 0.2s;
    }
    
    .toggle-group:hover {
        border-color: #d1d5db;
        background: #f9fafb;
    }
    
    .toggle-info {
        flex: 1;
    }
    
    .toggle-title {
        font-weight: 500;
        color: #374151;
        margin: 0 0 4px 0;
        font-size: 0.875rem;
    }
    
    .toggle-description {
        font-size: 0.75rem;
        color: #6b7280;
        margin: 0;
        line-height: 1.4;
    }
    
    /* Plan Upgrade Cards */
    .upgrade-cards {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 20px;
        margin-top: 16px;
    }
    
    .upgrade-card {
        border: 2px solid #e5e7eb;
        border-radius: 12px;
        padding: 20px;
        transition: all 0.2s;
        position: relative;
        background: white;
    }
    
    .upgrade-card.current {
        border-color: #667eea;
        background: linear-gradient(135deg, rgba(102, 126, 234, 0.05), rgba(118, 75, 162, 0.05));
    }
    
    .upgrade-card.recommended {
        border-color: #10b981;
        background: linear-gradient(135deg, rgba(16, 185, 129, 0.05), rgba(5, 150, 105, 0.05));
    }
    
    .plan-badge {
        position: absolute;
        top: -8px;
        right: 16px;
        padding: 4px 12px;
        border-radius: 12px;
        font-size: 0.7rem;
        font-weight: 600;
    }
    
    .plan-badge.current {
        background: #667eea;
        color: white;
    }
    
    .plan-badge.recommended {
        background: #10b981;
        color: white;
    }
    
    .plan-name {
        font-size: 1.25rem;
        font-weight: 600;
        color: #111827;
        margin: 0 0 8px 0;
    }
    
    .plan-price {
        font-size: 2rem;
        font-weight: bold;
        color: #111827;
        margin: 0 0 4px 0;
    }
    
    .plan-period {
        font-size: 0.875rem;
        color: #6b7280;
        margin: 0 0 16px 0;
    }
    
    .plan-features {
        list-style: none;
        padding: 0;
        margin: 0 0 20px 0;
    }
    
    .plan-feature {
        padding: 6px 0;
        font-size: 0.875rem;
        color: #374151;
        display: flex;
        align-items: center;
        gap: 8px;
    }
    
    .plan-feature.limited {
        color: #6b7280;
    }
    
    .plan-feature.unavailable {
        color: #9ca3af;
    }
    
    .plan-btn {
        width: 100%;
        padding: 10px 16px;
        border-radius: 6px;
        font-size: 0.875rem;
        font-weight: 500;
        border: none;
        cursor: pointer;
        transition: all 0.2s;
    }
    
    .plan-btn.current {
        background: #f3f4f6;
        color: #6b7280;
        cursor: default;
    }
    
    .plan-btn.upgrade {
        background: #667eea;
        color: white;
    }
    
    .plan-btn.upgrade:hover {
        background: #5b21b6;
        transform: translateY(-1px);
    }
    
    /* Danger Zone */
    .danger-zone {
        border: 2px solid #fee2e2;
        border-radius: 12px;
        padding: 20px;
        background: #fef2f2;
        margin-top: 24px;
    }
    
    .danger-zone h3 {
        color: #dc2626;
        font-size: 1.125rem;
        font-weight: 600;
        margin: 0 0 8px 0;
        display: flex;
        align-items: center;
        gap: 8px;
    }
    
    .danger-zone p {
        color: #991b1b;
        font-size: 0.875rem;
        margin: 0 0 16px 0;
        line-height: 1.5;
    }
    
    .danger-btn {
        background: #dc2626;
        color: white;
        border: none;
        padding: 10px 20px;
        border-radius: 6px;
        font-size: 0.875rem;
        font-weight: 500;
        cursor: pointer;
        transition: all 0.2s;
    }
    
    .danger-btn:hover {
        background: #b91c1c;
    }
    
    /* Loading State */
    .loading-spinner {
        display: inline-block;
        width: 16px;
        height: 16px;
        border: 2px solid transparent;
        border-top: 2px solid currentColor;
        border-radius: 50%;
        animation: spin 1s linear infinite;
    }
    
    @keyframes spin {
        0% { transform: rotate(0deg); }
        100% { transform: rotate(360deg); }
    }
    
    /* Success Message */
    .success-message {
        background: #d1fae5;
        border: 1px solid #a7f3d0;
        border-radius: 8px;
        padding: 12px 16px;
        margin-bottom: 16px;
        display: none;
        align-items: center;
        gap: 8px;
        color: #065f46;
        font-size: 0.875rem;
    }
    
    .success-message.show {
        display: flex;
    }
    
    /* Responsive Design */
    @media (max-width: 768px) {
        .mobile-menu-btn {
            display: block;
        }
        
        .sidebar-close {
            display: block;
        }
        
        .main-content {
            margin-left: 0;
            padding: 80px 16px 16px;
        }
        
        .sidebar {
            transform: translateX(-100%);
        }
        
        .sidebar.open {
            transform: translateX(0);
        }
        
        .settings-header {
            flex-direction: column;
            align-items: stretch;
        }
        
        .settings-actions {
            justify-content: space-between;
        }
        
        .settings-tabs {
            flex-direction: column;
            gap: 4px;
        }
        
        .form-row {
            grid-template-columns: 1fr;
        }
        
        .upgrade-cards {
            grid-template-columns: 1fr;
        }
        
        .toggle-group {
            flex-direction: column;
            align-items: stretch;
            gap: 12px;
        }
    }
    
    @media (max-width: 480px) {
        .settings-nav {
            padding: 16px;
        }
        
        .settings-section {
            padding: 16px;
        }
        
        .upgrade-card {
            padding: 16px;
        }
    }