How to change icon font to jpg image?

Question

css

Hey!
How can I change the font icon to an image?
On the example of the CodePen accordion
Tried to change this

a:after {
  content: '\e909';
}

On this

a:after {
  background-image: url(plus.jpg)
}

And it doesn't help

Answer 1

Add the width and height of the block to which you will set the background image. There are several in your code.

Answer 2

a:after {
  content: '';
  width: 50px;
  height: 50px;
  position: absolute;
  background-image: url(https://i.imgur.com/rWGmd4C.png)
}

https://jsfiddle.net/Lhhh71x8/