.cards-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 2rem;
            margin-bottom: 4rem;
        }

        .card {
            background: white;
            border-radius: 1rem;
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
            padding: 2rem;
            text-align: center;
            transition: all 0.3s ease;
        }

        .card:hover {
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
            transform: translateY(-5px);
        }

        .card-icon {
            width: 4rem;
            height: 4rem;
            border-radius: 50%;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1.5rem;
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
        }

        .card-icon svg {
            width: 2rem;
            height: 2rem;
            fill: white;
        }

        .card h3 {
            font-size: 1.5rem;
            font-weight: bold;
            color: #1e293b;
            margin-bottom: 1rem;
        }

        .card p {
            color: #64748b;
            margin-bottom: 1.5rem;
            line-height: 1.6;
        }

        .btn {
            width: 100%;
            padding: 0.75rem 1.5rem;
            border: none;
            border-radius: 0.75rem;
            font-weight: 600;
            font-size: 1rem;
            cursor: pointer;
            transition: all 0.3s ease;
            text-decoration: none;
            display: inline-block;
        }

        .btn-primary {
            background-color: #278382;
            color: white;
        }

        .btn-primary:hover {
            background-color: #1f6b6a;
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(39, 131, 130, 0.3);
        }

        .btn-disabled {
            background-color: #cbd5e1;
            color: #64748b;
            cursor: not-allowed;
        }

        .features {
            background: white;
            border-radius: 1rem;
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
            padding: 2rem;
        }

        .features h2 {
            font-size: 2rem;
            font-weight: bold;
            color: #1e293b;
            text-align: center;
            margin-bottom: 2rem;
        }

        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2rem;
        }

        .feature {
            text-align: center;
        }

        .feature-icon {
            width: 3rem;
            height: 3rem;
            border-radius: 50%;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1rem;
        }

        .feature-icon svg {
            width: 1.5rem;
            height: 1.5rem;
            fill: white;
        }

        .feature h3 {
            font-size: 1.125rem;
            font-weight: 600;
            color: #1e293b;
            margin-bottom: 0.5rem;
        }

        .feature p {
            color: #64748b;
            line-height: 1.6;
        }

        /* Modal Styles */
        .modal-overlay {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, 0.5);
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 1000;
            padding: 1rem;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
        }

        .modal-overlay.active {
            opacity: 1;
            visibility: visible;
        }

        .modal {
            background: white;
            border-radius: 1rem;
            box-shadow: 0 25px 50px rgba(0, 0, 0, 0.25);
            max-width: 600px;
            width: 100%;
            max-height: 90vh;
            overflow-y: auto;
            transform: scale(0.9);
            transition: transform 0.3s ease;
        }

        .modal-overlay.active .modal {
            transform: scale(1);
        }

        .modal-header {
            position: sticky;
            top: 0;
            background: white;
            border-bottom: 1px solid #e2e8f0;
            padding: 1.5rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            border-radius: 1rem 1rem 0 0;
        }

        .modal-title {
            display: flex;
            align-items: center;
        }

        .modal-title-icon {
            width: 3rem;
            height: 3rem;
            background: #f1f5f9;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
        }

        .modal-title-icon svg {
            width: 1.5rem;
            height: 1.5rem;
            fill: #64748b;
        }

        .modal-title-text h2 {
            font-size: 1.5rem;
            font-weight: bold;
            color: #1e293b;
        }

        .modal-title-text p {
            font-size: 0.875rem;
            color: #64748b;
        }

        .close-btn {
            width: 2.5rem;
            height: 2.5rem;
            border: none;
            background: none;
            border-radius: 50%;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: background-color 0.2s ease;
        }

        .close-btn:hover {
            background: #f1f5f9;
        }

        .close-btn svg {
            width: 1.5rem;
            height: 1.5rem;
            fill: #64748b;
        }

        .modal-content {
            padding: 1.5rem;
        }

        .section {
            margin-bottom: 1.5rem;
        }

        .section h3 {
            font-size: 1.125rem;
            font-weight: 600;
            color: #374151;
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
        }

        .section h3 svg {
            width: 1.25rem;
            height: 1.25rem;
            margin-right: 0.5rem;
            fill: currentColor;
        }

        .gender-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 1rem;
        }

        .gender-btn {
            padding: 1rem;
            border: 2px solid #e2e8f0;
            border-radius: 0.75rem;
            background: white;
            cursor: pointer;
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 500;
        }

        .gender-btn svg {
            width: 1.25rem;
            height: 1.25rem;
            margin-right: 0.5rem;
            fill: currentColor;
        }

        .gender-btn.active.male {
            border-color: #2563eb;
            background-color: #eff6ff;
            color: #2563eb;
            box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15);
        }

        .gender-btn.active.female {
            border-color: #e9692e;
            background-color: #fff7ed;
            color: #e9692e;
            box-shadow: 0 4px 12px rgba(233, 105, 46, 0.15);
        }

        .unit-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 1rem;
        }

        .unit-btn {
            padding: 0.75rem;
            border: 2px solid #e2e8f0;
            border-radius: 0.5rem;
            background: white;
            cursor: pointer;
            transition: all 0.3s ease;
            font-weight: 500;
        }

        .unit-btn.active {
            border-color: #278382;
            background-color: #f0fdfa;
            color: #278382;
        }

        .input-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 1.5rem;
        }

        .input-group {
            display: flex;
            flex-direction: column;
        }

        .input-group label {
            font-size: 0.875rem;
            font-weight: 600;
            color: #374151;
            margin-bottom: 0.5rem;
            display: flex;
            align-items: center;
        }

        .input-group label svg {
            width: 1rem;
            height: 1rem;
            margin-right: 0.5rem;
            fill: currentColor;
        }

        .input-group input {
            padding: 1rem;
            border: 2px solid #e2e8f0;
            border-radius: 0.75rem;
            font-size: 1rem;
            font-weight: 500;
            color: #374151;
            transition: border-color 0.3s ease;
        }

        .input-group select{
             padding: 1rem;
            border: 2px solid #e2e8f0;
            border-radius: 0.75rem;
            font-size: 1rem;
            font-weight: 500;
            color: #374151;
            transition: border-color 0.3s ease;
        }

        .input-group input:focus {
            outline: none;
            border-color: #278382;
        }

        .input-group input.filled {
            border-color: #278382;
        }

        .reset-btn {
            padding: 0.5rem 1.5rem;
            border: 1px solid #cbd5e1;
            background: white;
            color: #64748b;
            border-radius: 0.5rem;
            cursor: pointer;
            transition: background-color 0.2s ease;
        }

        .reset-btn:hover {
            background: #f8fafc;
        }

        .results {
            border-top: 1px solid #e2e8f0;
            padding-top: 1.5rem;
            margin-top: 1.5rem;
        }

        .results h3 {
            font-size: 1.25rem;
            font-weight: bold;
            color: #1e293b;
            text-align: center;
            margin-bottom: 1rem;
        }

        .bmi-display {
            text-align: center;
            margin-bottom: 1.5rem;
        }

        .bmi-circle {
            width: 5rem;
            height: 5rem;
            border-radius: 50%;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 1.5rem;
            font-weight: bold;
            margin-bottom: 0.75rem;
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
        }

        .bmi-category {
            font-size: 1.25rem;
            font-weight: bold;
            margin-bottom: 0.5rem;
        }

        .bmi-description {
            color: #64748b;
        }

        .categories-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
            gap: 0.75rem;
            margin-top: 1rem;
        }

        .category-item {
            padding: 0.75rem;
            border: 2px solid #e2e8f0;
            border-radius: 0.5rem;
            transition: all 0.3s ease;
        }

        .category-item.active {
            border-color: currentColor;
            background-color: rgba(0, 0, 0, 0.05);
        }

        .category-item-header {
            display: flex;
            align-items: center;
            margin-bottom: 0.25rem;
        }

        .category-dot {
            width: 0.75rem;
            height: 0.75rem;
            border-radius: 50%;
            margin-right: 0.75rem;
        }

        .category-name {
            font-weight: 500;
            color: #374151;
            font-size: 0.875rem;
        }

        .category-range {
            font-size: 0.75rem;
            color: #64748b;
            margin-left: 1.5rem;
        }

        .health-tip {
            margin-top: 1.5rem;
            padding: 1rem;
            background: #f8fafc;
            border-radius: 0.5rem;
        }

        .health-tip h4 {
            font-weight: 600;
            color: #374151;
            margin-bottom: 0.5rem;
            font-size: 0.875rem;
        }

        .health-tip p {
            font-size: 0.75rem;
            color: #64748b;
            line-height: 1.5;
        }

        .disclaimer {
            text-align: center;
            color: #64748b;
            font-size: 0.75rem;
            margin-top: 1.5rem;
            padding-top: 1rem;
            border-top: 1px solid #e2e8f0;
        }

        .disclaimer p {
            margin-bottom: 0.25rem;
        }

        .text-center {
            text-align: center;
        }

        .hidden {
            display: none;
        }

        @media (max-width: 768px) {
            .input-grid {
                grid-template-columns: 1fr;
            }
            
            .gender-grid {
                grid-template-columns: 1fr;
            }
            
            .categories-grid {
                grid-template-columns: 1fr 1fr;
            }
            
            .header h1 {
                font-size: 2rem;
            }
            
            .modal {
                margin: 0.5rem;
            }
        }