Make responsive designs for the website

Add responsive design media queries for the website. For reference check out https://www.w3schools.com/css/css_rwd_mediaqueries.asp

Example: : 
<style>
body {
  background-color: lightgreen;
}

@media only screen and (max-width: 600px) {
  body {
    background-color: lightblue;
  }
}
</style>

Note : You do not need to be assigned this issue. You can directly submit a PR.