Form font size is too small - how can I change it?

I'm using the FIVE template and I would like my form font to be larger. I'm attaching a screenshot of it below. It is actually magnified in the picture below.. it shows much smaller to me. Not sure why it's magnified.

The solution & css code provided in this thread did not work for me.

I also tried changing the body text as one of those solutions suggested that it's where the font style is pulled from. That did not work either.

The solution & css code provided in this thread did not work either. I tried it in both the main css for all pages, and then on the buy now page where the form pops up.

This is the page where the form is; you need to 'add to cart' for it to pop up.

Any help would be very much appreciated!

Custom CSS code.

This increases font size of the list of selectable items:

.form-wrapper .field-list .field .option{
   font-size:18px;
}

This increases the text in the message area:

.form-wrapper .field-list .field .field-element{
   font-size:18px;
}

Change the font size from 18px to whatever your preference is.

Thanks ghostcat! you're a rock star! <3

There's one field missing, the description text for the fields. Here's the code:

.form-wrapper .field-list .field .description{
    font-size:18px;
}