Hi Paul!
I’ve added the button and text to my site.
They both have Poppins Semi Bold font and size set to 14 px. As you can see below they are the same.
Please click on button and check design settings in Inspector.
When you add a button its font is set to bold by default. It can cause the confusion.
If the issue still persists on your end please reply in this thread with some screenshots and more information (font styles, size, etc.).
Thanks !