Hey there Hannah,
How are you doing today?
If you’re referring to the home page header image http://screencast.com/t/ykEqwup0 you can replace it with your own in Appearance >> Convac Options >> Header Settings http://screencast.com/t/RMKZI9sIG.
If you’re looking to replace that image with the color of your choice you can do that with some custom CSS. Please try adding the following CSS code in the style.css file of your child theme or add it in your site using the following plugin:
http://wordpress.org/plugins/simple-custom-css
.home #wrapper .header-top-wrap, .home.front-page #wrapper .header-top-wrap {
background: #000;
}
This should replace the image on home page with the color. Replace color hex value with the color of your choice. You can use sites similar to this one to get hex value for the color of your choice:
http://www.color-hex.com/
If this doesn’t work could you please post link to your site so I can take a look?
Hope this helps 🙂
Best regards,
Bojan