RE: How to change the font of Submit button on Marketing form landing page?
Hi,
The style of the submit button can be adjusted by editing the HTML of the form.
For example, there is a submit button and a normal button in the following screenshot.
Click the HTML designer in the following red circle.

Find the code of the button and copy the style elements.

Find the definition of the style for the submit button and adjust the code block with the styles copied.

Then switch back to the Designer tab.
You'll see the following effect.
