Hi
When the header image or top slider exist, the menu will be transparent, otherwise, it will not transparent.
If you don’t want this effect, please go to “Samsara Options > Custom Styles > Opacity Of Navigation”. set the value to 1.
If you want to change the body background color, you have to made some custom works with additional CSS, for example, if you changed the background color, maybe you also need to check the text color, link color and etc. The customization issue is not included in the support, just tell you a general idea below
Add the following CSS into “Samsara Options > Custom Styles > CSS code”
body{background-color:your color code;}
If you just want to change some section background color or image just like my demo site, you can make that change with visual composer.
Please refer to this video. https://www.youtube.com/watch?v=Nci9UUGtmLQ
Thanks