:root {
            --primary: #4a90e2;
            --primary-dark: #357abd;
            --success: #34c759;
            --warning: #ff9500;
            --danger: #ff3b30;
            --surface: #ffffff;
            --surface-elevated: #f8f9fa;
            --text-primary: #1a1a1a;
            --text-secondary: #666666;
            --border: #e1e4e8;
        }

        .header-section {
            max-width: 800px;
            margin: 2rem auto;
            padding: 2rem;
            background: var(--surface-elevated);
            border-radius: 12px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            text-align: center;
        }

        .header-section h1 {
            font-size: 2.5rem;
            margin-bottom: 1rem;
            color: var(--text-primary);
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
        }

        .header-section p {
            font-size: 1.1rem;
            line-height: 1.6;
            color: var(--text-secondary);
            margin-bottom: 1.5rem;
        }

        .calculator {
            max-width: 800px;
            margin: 2rem auto;
            padding: 2rem;
            background: var(--surface);
            border-radius: 12px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
        }

        .input-group {
            margin-bottom: 1.5rem;
        }

        .input-group label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 500;
            color: var(--text-primary);
        }

        .input-control {
            width: 100%;
            padding: 0.75rem;
            border: 2px solid var(--border);
            border-radius: 8px;
            font-size: 1rem;
            transition: all 0.2s ease;
        }

        .input-control:focus {
            border-color: var(--primary);
            box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
            outline: none;
        }

        .range-container {
            position: relative;
            padding: 1rem 0;
        }

        .range-value {
            position: absolute;
            right: 0;
            top: 0;
            background: var(--primary);
            color: white;
            padding: 0.25rem 0.75rem;
            border-radius: 12px;
            font-size: 0.875rem;
            font-weight: 500;
        }

        input[type="range"] {
            width: 100%;
            height: 6px;
            background: var(--border);
            border-radius: 3px;
            outline: none;
            -webkit-appearance: none;
        }

        input[type="range"]::-webkit-slider-thumb {
            -webkit-appearance: none;
            width: 20px;
            height: 20px;
            background: var(--primary);
            border-radius: 50%;
            cursor: pointer;
            transition: all 0.2s ease;
        }

        input[type="range"]::-webkit-slider-thumb:hover {
            transform: scale(1.1);
        }

        .calculate-btn {
            width: 100%;
            padding: 1rem;
            background: linear-gradient(135deg, var(--primary), var(--primary-dark));
            color: white;
            border: none;
            border-radius: 8px;
            font-size: 1.1rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s ease;
            position: relative;
            overflow: hidden;
        }

        .calculate-btn:hover {
            transform: translateY(-1px);
            box-shadow: 0 4px 12px rgba(74, 144, 226, 0.2);
        }

        .calculate-btn:active {
            transform: translateY(0);
        }

        .calculate-btn.loading {
            pointer-events: none;
            opacity: 0.8;
        }

        .calculate-btn.loading::after {
            content: '';
            position: absolute;
            width: 20px;
            height: 20px;
            top: 50%;
            left: 50%;
            margin: -10px 0 0 -10px;
            border: 2px solid rgba(255, 255, 255, 0.3);
            border-top-color: white;
            border-radius: 50%;
            animation: spin 0.8s linear infinite;
        }

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

        .results {
            max-width: 800px;
            margin: 2rem auto;
            padding: 2rem;
            background: var(--surface);
            border-radius: 12px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
        }

        .results[x-cloak] {
            display: none !important;
        }

        .result-card {
            background: var(--surface-elevated);
            border-radius: 8px;
            padding: 1.5rem;
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 1rem;
        }

        .result-icon {
            width: 48px;
            height: 48px;
            background: var(--primary);
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            color: white;
        }

        .result-content {
            flex: 1;
        }

        .result-label {
            font-size: 0.875rem;
            color: var(--text-secondary);
            margin-bottom: 0.25rem;
        }

        .result-value {
            font-size: 1.5rem;
            font-weight: 600;
            color: var(--text-primary);
        }

        .timeline {
            margin-top: 2rem;
        }

        .timeline-item {
            display: flex;
            align-items: center;
            gap: 1rem;
            margin-bottom: 1rem;
            padding: 1rem;
            background: var(--surface-elevated);
            border-radius: 8px;
            transition: all 0.2s ease;
        }

        .timeline-item:hover {
            transform: translateX(4px);
        }

        .timeline-year {
            min-width: 80px;
            font-weight: 500;
            color: var(--text-primary);
        }

        .timeline-bar {
            flex: 1;
            height: 8px;
            background: var(--border);
            border-radius: 4px;
            overflow: hidden;
        }

        .timeline-progress {
            height: 100%;
            background: linear-gradient(90deg, var(--primary), var(--primary-dark));
            border-radius: 4px;
            transition: width 0.3s ease;
        }

        .timeline-value {
            min-width: 120px;
            text-align: right;
            font-weight: 500;
            color: var(--text-primary);
        }

        @media (max-width: 768px) {
            .header-section {
                padding: 1.5rem;
                margin: 1rem;
            }

            .header-section h1 {
                font-size: 2rem;
            }

            .calculator,
            .results {
                margin: 1rem;
                padding: 1.5rem;
            }

            .timeline-item {
                flex-direction: column;
                align-items: flex-start;
                gap: 0.5rem;
            }

            .timeline-year {
                min-width: auto;
            }

            .timeline-value {
                min-width: auto;
                text-align: left;
            }
        }