Change Color Background on mainnav li

My customer wants main menu a background color. I have created a childtheme and inserted this text on childTheme style.css

    #mainnav ul li {
    background-color: # 3838388a
    }

unfortunately, nothing changes on the side!
here the link urv.grafikweb.eu

I can not find the mistake!

Hello there,

Try this code:

    #mainnav ul.menu > li > a {
      background-color: #fff000;
      color: #ff0000;
      padding-left: 7px;
      padding-right: 7px;
    }

Regards,
Kharis

Thank you! Works perfect! Great

You’re welcome!

Please let us know in a new topic if you have any further questions, or if we can provide you with any other assistance.

Regards,
Kharis