So they gave me a photoshop file to create a contact form page. The requirements were: responsive design, IE9 compatible, form validation, use all assets from PSD file, among others. It took me a week to do a pixel perfect contact page using their design, IE9 compatible and for the contact form (name, email, phone and message) i used jQuery. They rejected me because the form was validated via jQuery. It was a static page, so it was the simplest thing to do. I've had other interviews and challenges where they are really specific: code an app using React or Angular that does... I was really mad because they weren't specific about tools and they didn't want to discuss my solution, I think the most challenging part of their test was creating HTML code from a PSD file and adding IE9 compatibility, the contact form was really easy, some HTML5 form validation or a jQuery plugin could have done the job .