Make the background color of the header become transparent

Hello,

As per title how do I do it?

Hello there,

Try adding this CSS code to Appearance > Customize > Additional CSS from dashboard.

    .site-header.float-header {
      background-color: transparent;  
    }

    .site-header.float-header .site-title,
    .site-header.float-header .site-title a,
    .site-header.float-header .site-description {
      color: #000;
    }

    .site-header.float-header #mainnav ul.menu > li > a {
      color: #000;
    }

Regards,
Kharis