Tip calculator app

Hi,

Challange with tip calculator.

I think that, work of this calculator is correct, below instruction.

Select tip, click at button one of 5%, 10%, 15%, 25%, 50%. Insert value in bill input and number of people, then click one of button. When number of people is equal zero and you'll click at button, then you'll see error. After change at another number then tip will work.

If you want to get tip with custom value. Correctly include bill value and number of people. After this step you can insert custom value. Calculator will show you tip.

While number of people is equal zero and you'll include some value in custom input. Then you'll see error. You have to insert other value then include again which you want.

Thank you for feedback.