Header background-color

1. How do if make the header and menu background transparent? I cleared out mega menu plugin and want to start back at the theme's original options and go forward making changes. In the header & menu area the background-color is white. I am trying to assign it rgba (0,0,0,0.1). I can get it to change using the Chrome developer tool but when I put it in the Additional CSS section, click Publish, it doesn't work. My CSS code is .nav-primary {background-color: rgba(0,0,0,0.1);}. 2. Also, the widget header right side does not appear anymore but the content is in the widget. Need the header right widget area information to display 3. The sticky header has lost it's color, which was .is-sticky{ background: rgba(210,210,210,1);}. This custom CSS is still in the Additional CSS section. Something appears to be overwriting my custom CSS. Email me to get your sign in information. Web site has 'Under Construction' active. Client does not want website live. Please help in resolving these issues. Thanks.