Is applying ::before to input[type=submit] possible? [duplicate]

This question already has an answer here:

• Can I use the :after pseudo-element on an input field? 10 answers

Let's say you have a form input button that you want to style with CSS, but you also want to use "::before" to append text before the styling. How would you do that? Is that even possible?

input[type=submit]::before {} (this doesn't work)

Is editing "value='blahblahbuttontext'" in the form the only way to achieve this?

Thanks,

-- MP