CodePen

HTML

            
              <div class="box">You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. You wish you could see this text. </div>
            
          
!

↑ Insert the most common viewport meta tag

CSS

            
              .box {
  margin: 50px auto;
  color: blue;
  width: 400px;
  column-count: 2;
  column-width: 150px;
  column-gap: 20px;
  column-rule: 400px solid blue;
}
            
          
!
? ?
? ?
Must be a valid URL.
+ add another resource
via CSS Lint

JS

            
              
            
          
!
Must be a valid URL.
+ add another resource
via JS Hint
Loading ..................