Features of this VAT Calculator

1. User Inputs:
   • Amount field for entering the base value
   • VAT rate selector with common rates (5%, 10%, 15%, 20%, 25%) and custom option
   • Calculation type (add VAT to amount or subtract VAT from amount)
2. Functionality:
   • Calculates VAT amount and total amount based on user inputs
   • Handles both adding VAT to a net amount and extracting VAT from a gross amount
   • Shows/hides custom rate field based on selection
3. Display:
   • Clean, responsive design
   • Clear results section showing:
     • Original amount
     • VAT rate
     • VAT amount
     • Total amount
4. Validation:
   • Checks for valid numeric inputs
   • Shows alerts for invalid entries
   • Added a proper VAT calculator illustration using a financial/calculator-themed image from Unsplash
   • Implemented responsive images using the <picture> element with:
     • Mobile-optimized version (320px wide) for screens ≤480px
     • Desktop version (800px wide) for larger screens
   • Improved the image styling with object-fit: cover for better presentation
   • Used a more semantic class name “calculator-illustration”
   • Added proper alt text describing the illustration
   • Maintained all the original VAT calculator functionality
   • The image will automatically switch between mobile and desktop versions based on screen size, optimizing both performance and visual quality. The illustration helps make the calculator more visually appealing while maintaining its full functionality