[Theme Horse Support Team]

Hi Bdrakefore,

If you have customize the CSS code then your code will be lost after you update the theme.

To change the slider title background-color Go to Appearance -> Theme Options -> Design Options Tab -> Custom CSS paste the following CSS code and Click on save all changes button:

.featured-text .featured-title {
    background-color: #90C140;
}

You can have this feature if you upgrade it to Interface pro theme a premium version of Interface theme.

Thank you!