Hello, I recently started my two site named LoginWorldz.com and LoginWelt.com and I want to see the settings of font and header logo size for mobile version of sites.
Thanks and Regards
Aiman Khan
Regarding your query, Magento does not provide such kind of setting for mobile screens.
So, you need to add CSS for the logo and font size.
Magento 2 logo change & logo size
Your current store theme determines the size and location of the logo by default. The default Magento 2 logo is saved as an SVG file. The desired logo can be saved in any of the file types: GIF, PNG, JPG, or JPEG and uploaded from the admin panel of your website.
To find the default Magento logo and change it for a new one, navigate to:
The Admin Panel> Content> Configuration> Select Your Current Theme> Header;
!For Magento 2.x.x - Magento 2.1.x use this path: the Admin Panel> Stores> Settings> Configuration> General> Design> Header!
It is always better to keep font and logo small. It's easier to read on a small device. The fonts are also not as legible on a small screen. Fonts also tend to be more readable when they are smaller. Visit this https://masterbundles.com/girly-fonts/ site for premium girly fonts. I am not sure if this would work for all mobile sites, but I think it is better to test it out on a few different sites and see what works best for each site.