If you use Grigora’s Kit Blocks, you’ll be able to edit settings for tablet and mobile. Its not possible in theme files, but you can attach custom classes to blocks and then add a custom css targeting those blocks.
Where are those tablet and mobile settings located? This is what I’m looking for and not able to find. If I’m adding custom CSS classes to blocks, where is the custom CSS going? Do I have to add a custom HTML block to each page to add the custom CSS since It can’t be done in the theme files?
If you use Blocks from Grigora Blocks library, you’ll see those settings in Right Sidebar. But if you’re looking for those settings in WordPress Core Blocks, it wont be available there. For Custom CSS, yes, you are correct, adding Custom HTML Code is only the way to do it right now. The new Full Site Editing is missing the options to add custom CSS. Otherwise, you can take help of plugins like “Code Snippets” to add custom CSS globally.
