Calculator using HTML, CSS and JS

About

This is simple calculator. Although the page isn't responsive but, it works decently fine.

Learnings

HTML

I created some buttons, added onclick attribute that is a kind of event listener and we pass a Java script function to it's value which gets called on the button click. Added some class attributes to function buttons.

CSS

Shaped the button in round form.

JS

Learned to create a global variable. Used eval() method to evaluate the expression.