The arrow in the chevron icon in the Collapsible's section will not show

Hello anyone who can help!

In the Collapsible section for The Ultimate HTML5, the arrow in the chevron icon will not show and I have tried to do everything to make it show.

If someone could lead me in the right direction, it would be much appreciated!

Thank you!

Hi, same thing happened to me, so I copied this svg into the images folder, and used it separately with an img tag and icon class:

<img class="icon" src="images/chevron.svg" alt="Chevron icon" />