How can I put the white zone for logo and menu with a bigger height, so that I can put the logo bigger. Like that it is real small and disproportionate with the rest of the site infos.
Unfortunately there's not built-in option for logo height because the header height is fixed (60px + 15px top padding + 15px bottom padding). By the way, logo 200px tall = header 230px tall, and imho it's not really wise displaying an header taking so much space
In any case, this tweak may require a large number of modifications and theme customisation is out of the support scope, I am sorry. But I'll try to put you on the right track:
Let's say you want the logo is 80px tall (+20px), then you need set a new .site-headerheight (i.e. 110px instead of 90px), the .menu-toggle height (i.e. 80px instead of 60px), set the menu items and/or language links line height to 80px, add some margin-top (+20px) to each .site-content selector you'll find in the style.css file, etc. But please consider that there may be something else that I am missing thought
In other words, that's a little bit tricky but definitely possible. Using the Chrome inspector may help you to understand what's to be changed. Hope that helps!