Hello,
Actually, these Menu Items in the concerned Demo use the Primary Color defined in the Theme Settings. So, if you want to generally change the Color overall then you can go to Dashboard > Theme Settings > Styles and colors > Colors > there you can change the Primary Color and these will change accordingly: https://snipboard.io/vTGrtC.jpg
Or if you want to specifically try to change the colors for the Menus then you can try using the Advanced Typography which can be find under the Dashboard > Theme Settings > Typography > Advanced > there from the dropdown you can select specific Menu/Navigation-related selectors > and then you can define Font formatting there for those which includes Color and Color on hover too: https://snipboard.io/t0Ts1A.jpg
And lastly, if you specifically want to just change the Background Color here then a Custom CSS would be required to apply. Here is the Custom CSS that you try out if you want:
.wd-nav.wd-style-bg>li>a:before {
background-color: green !important;
}
Location to paste Custom CSS, go to Dashboard >> Theme Settings >> Custom CSS >> Global CSS section >> paste the CSS.
In the above CSS, you can change the color name to your choice of name or hex code.
Hope this helps !
Best Regards.