:root {
            --primary-color: #2d6a4f;
            --secondary-color: #40916c;
            --accent-color: #1b4332;
            --light-green: #95d5b2;
            --light-gray: #f8f9fa;
            --border-color: #eaeaea;
            --text-color: #333;
            --text-muted: #6c757d;
            --warning-color: #ffc107;
            --danger-color: #dc3545;
            --success-color: #28a745;
            --math-color: #6f42c1;
            --calc-color: #40916c;
        } 
        .page-header {
            background: linear-gradient(135deg, rgba(149, 213, 178, 0.2) 0%, rgba(45, 106, 79, 0.4) 100%);
            padding: 1.5rem 0;
            margin-bottom: 2rem;
            border-bottom: 1px solid rgba(45, 106, 79, 0.2);
            position: relative;
            overflow: hidden;    color: var(--text-color);
        } 
        
        .breadcrumb {
            background-color: transparent;
            padding: 0.5rem 0;
            margin-bottom: 0.5rem;
        }
        
        .breadcrumb-item a {
            color: var(--text-muted);
            text-decoration: none;
        }
        
        .breadcrumb-item.active {
            color: var(--text-color);
        }
         
        /* Curve Type Selector */
        .curve-type-selector {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
            margin-bottom: 2rem;
        }
        
        .curve-type-btn {
            flex: 1;
            min-width: 150px;
            background-color: rgba(45, 106, 79, 0.1);
            border: 1px solid rgba(45, 106, 79, 0.2);
            border-radius: 6px;
            padding: 0.25rem;
            font-size: 1rem;
            color: var(--primary-color);
            cursor: pointer;
            transition: all 0.3s;
            text-align: center;
            font-weight: 600;
        }
        
        .curve-type-btn.active {
            background-color: var(--primary-color);
            color: white;
        }
        
        .curve-type-btn:hover:not(.active) {
            background-color: rgba(45, 106, 79, 0.2);
        }
         
        .math-result {
            padding: 12px;
            background-color: white;
            border-radius: 4px;
            border: 1px solid #eee;
            font-size: 1.1rem;
            margin: 10px 0;
            font-family: 'Courier New', monospace;
        }
        
        .curve-result {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary-color);
            text-align: center;
            margin: 1rem 0;
            padding: 1rem;
            background-color: rgba(149, 213, 178, 0.1);
            border-radius: 8px;
            border-left: 5px solid var(--secondary-color);
        }
        
        .info-box {
            background-color: rgba(45, 106, 79, 0.05);
            border-left: 3px solid var(--primary-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .math-box {
            background-color: rgba(111, 66, 193, 0.05);
            border-left: 3px solid var(--math-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        /* Chart Container */
        .chart-container {
            position: relative;
            height: 500px;
            width: 100%;
            margin: 2rem 0;
        }
        
        /* Content Sections */
        .section-title {
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--primary-color);
            padding-bottom: 0.5rem;
            border-bottom: 1px solid var(--border-color);
        }
        
        .usage-step {
            display: flex;
            margin-bottom: 1.5rem;
            align-items: flex-start;
        }
        
        .step-number {
            width: 28px;
            height: 28px;
            background-color: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
            flex-shrink: 0;
            font-weight: 600;
            font-size: 0.9rem;
        }
        
        /* Related Tools */
        .related-tools {
            background-color: white;
            border-radius: 8px;
            border: 1px solid var(--border-color); 
            margin-bottom: 1.5rem;
            padding: 1.5rem;
        }
        
        .related-title {
            font-weight: 600;
            margin-bottom: 1.25rem;
            padding-bottom: 0.75rem; 
            color: var(--primary-color);
            border-bottom: 1px solid var(--border-color);
        }
        
        /* Enhanced CSS from previous version */
        .standards-check {
            background-color: rgba(255, 193, 7, 0.1);
            border-left: 3px solid var(--warning-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .standards-item {
            display: flex;
            align-items: center;
            margin-bottom: 0.5rem;
        }
        
        .standards-icon {
            margin-right: 0.5rem;
            font-size: 1.2rem;
        }
        
        .standards-pass {
            color: var(--success-color);
        }
        
        .standards-warning {
            color: var(--warning-color);
        }
        
        .standards-fail {
            color: var(--danger-color);
        }
        
        .advanced-toggle {
            background-color: rgba(45, 106, 79, 0.1);
            border: 1px solid rgba(45, 106, 79, 0.2);
            border-radius: 6px;
            padding: 0.75rem;
            margin-bottom: 1rem;
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        
        .advanced-content {
            display: none;
            padding: 1rem;
            background-color: rgba(45, 106, 79, 0.05);
            border-radius: 6px;
            margin-bottom: 1rem;
        }
        
        .advanced-content.show {
            display: block;
        }
        
        /* Result cards */
        .result-cards {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .result-card {
            background-color: white;
            border-radius: 6px;
            padding: 1.5rem;
            text-align: center;
            border: 1px solid var(--border-color);
        }
        
        .result-value {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        
        .result-label {
            font-size: 0.9rem;
            color: var(--text-muted);
        }
        
        .calculation-step {
            margin-bottom: 1.5rem;
            padding-bottom: 1.5rem;
            border-bottom: 1px dashed var(--border-color);
        }
        
        .step-title {
            font-weight: 600;
            color: var(--math-color);
            margin-bottom: 0.5rem;
        }
        
        .generating-indicator {
            display: none;
            text-align: center;
            padding: 1rem;
            color: var(--text-muted);
        }
        
        .loading-animation {
            display: inline-block;
            width: 20px;
            height: 20px;
            border: 3px solid rgba(45, 106, 79, 0.3);
            border-radius: 50%;
            border-top-color: var(--primary-color);
            animation: spin 1s ease-in-out infinite;
            margin-right: 10px;
        }
        
        @keyframes spin {
            to { transform: rotate(360deg); }
        }
        
        .progress-indicator {
            height: 4px;
            background-color: var(--light-gray);
            border-radius: 2px;
            overflow: hidden;
            margin: 1rem 0;
        }
        
        .progress-bar {
            height: 100%;
            background-color: var(--primary-color);
            width: 0%;
            transition: width 0.3s ease;
        }
        
        .enhanced-result-card {
            background-color: white;
            border-radius: 8px;
            padding: 1.5rem;
            border: 1px solid var(--border-color);
            margin-bottom: 1.5rem;
        }
        
        .enhanced-result-title {
            font-weight: 600;
            color: var(--primary-color);
            margin-bottom: 1rem;
            padding-bottom: 0.5rem;
            border-bottom: 2px solid var(--secondary-color);
        }
        
        .calculation-details {
            background-color: white;
            border-radius: 6px;
            padding: 1.5rem;
            margin: 1.5rem 0;
            border: 1px solid var(--border-color);
        }
        
        .detail-row {
            display: flex;
            justify-content: space-between;
            padding: 0.5rem 0;
            border-bottom: 1px solid var(--border-color);
        }
        
        .detail-row:last-child {
            border-bottom: none;
        }
        
        .coordinate-table {
            width: 100%;
            border-collapse: collapse;
            margin: 1.5rem 0;
        }
        
        .coordinate-table th, .coordinate-table td {
            padding: 0.75rem;
            text-align: center;
            border: 1px solid var(--border-color);
        }
        
        .coordinate-table th {
            background-color: var(--light-gray);
            font-weight: 600;
        }
        
        .coordinate-table tr:nth-child(even) {
            background-color: rgba(45, 106, 79, 0.05);
        }
        
        .toast-container {
            position: fixed;
            bottom: 20px;
            right: 20px;
            z-index: 1050;
        }
        
        /* Graph legend */
        .graph-legend {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 1.5rem;
            margin-top: 1rem;
        }
        
        .legend-item {
            display: flex;
            align-items: center;
        }
        
        .legend-color {
            width: 20px;
            height: 4px;
            margin-right: 0.5rem;
        }
        
        .tangent-color {
            background-color: rgba(45, 106, 79, 0.8);
        }
        
        .curve-color {
            background-color: rgba(64, 145, 108, 0.8);
        }.curve-tab-content{display:none}
 .active{display:block}
        .point-color {
            width: 10px;
            height: 10px;
            border-radius: 50%;
            margin-right: 0.5rem;
            background-color: rgba(220, 53, 69, 0.8);
        }
        
        /* Vertical curve specific */
        .elevation-profile {
            position: relative;
            height: 200px;
            background-color: var(--light-gray);
            border-radius: 6px;
            margin: 1.5rem 0;
            overflow: hidden;
        }
        
        /* Responsive */
        @media (max-width: 768px) {
            .tool-card {
                padding: 1.5rem;
            }
            
            .curve-type-selector {
                flex-direction: column;
            }
            
            .result-cards {
                grid-template-columns: repeat(2, 1fr);
            }
        }