Hi,

Please add this code to the Theme Settings > Custom CSS > Global:

.wd-side-hidden.wd-opened {
background-color: black !important;
}

Change the color as per your need.

You can change the font by means of the Advanced typography option, which allows you to choose the item from a drop-down or insert your custom CSS class. Please navigate to the Theme Settings > Typography > Advanced Typography.

Here is the documentation providing more detailed instructions: https://xtemos.com/docs/woodmart/advanced-typography-settings/

Best Regards.