Remove Hamburger & Change header dimensions on mobilc

I’ve reached out to Vela Themes several times for support, but received no reply or acknowledgement, so I’m hoping someone can help me here.

I’m trying to adjust two things on mobile view:

A) Totally remove the hamburger menu from right side of mobile view or at least reduce the width of the slide out;
B) Reduce the amount of white space between the logo section and the first block of text below that. Screenshots are at https://www.screencast.com/t/VxhSEaWbwp

I assume CSS could do this but have no idea what code to use.

Thanks in advance!

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