How to change header size and style

Hi everyone.

I'm currently trying to set up a webpage for an arts project featuring texts, in the form of poetry and prose, for a group of writers. 

For the design we all agreed on something simplistic like this page here: rapsode.no. No flashy imagery, just our works with a thick header like shown in the example.

However I'm at a loss and seemingly unable to change anything about my header, except for placement. Will i need a custom CSS for this? And how would I go about doing so?

Thanks in advance!

Can you share link to your site?

Hello, and thanks for your reply!

www.litterærsalong.net

I found it easier making a logo through Canva than playing around with the title header, but I would still like a custom CSS for making the logo bigger. What I have now is a placeholder from Pages.

I actually found one of your previous replies, and I'm able to solve this now. Anyway, thanks for looking into my question! 

CSS for 7.1 if anyone else is in need

.header-title-logo img {
    max-height: 250px;
}