Icons not showing properly in Divi Child Theme

I'm working on a website (using Divi) and the icons don't show up correctly when I activate the child theme.

I've attached a picture to show the problem I am having:

This only happens when I activate the child theme, when I go back to the Divi theme, everything goes back to normal.

Additional info:

• I used a Divi child theme generator for the child themes.
• I used CSS and Elegant Themes Icon codes for the Icons.

Here is an example of the CSS I use for the icons:

.menu-donate:before {
    font-family: 'ETmodules';
    content: "\e089";
      color: #2a2f36;
        margin-right: 6px;
        margin-top: -2px;
    float: left;
}

How can I make the icons compatible with the Divi child theme?

Thanks in advance

I figured it out, after activating the child theme, the CSS was changed and the "\" was removed from the "\e089".

I added the "\" back in and it's working normally.