Change the Background Colour of the Search Bar

Have a look at this post: https://wpgeodirectory.com/docs/customizing-your-style/
We’d need at least a URL if you need us to have a look, but most likely this is the CSS to add to the stylesheet of your child theme:

.geodir-loc-bar-in {
    background: #f3f3f3;
}

Replace the color.

You have to add it to your custom CSS, wherever you do that normally.
You should be using a child theme with Avada, so you can add it to the style.css file of the child theme.
or you can add at GD > design > scripts.

You’re welcome 🙂