Reduce CSS padding... border on "Paragraph3" text style

We are new to Squarespace and don't know the embedded object classes that are called "Paragraph 2", "Paragraph 3", and "Heading 3". For now, I'm using these three text styles on our website to assign the text colors with color themes. But the padding, or maybe it's line-height wrapped around the text styles are huge. Like everything is double-spaced. If it's line-height, I'd like to throw an .h3 {line-height= something} in the advanced CSS area but don't know what the objects are called. Or if there are any other classes wrapped around those like @media or page widths (like in Bootstrap). For example is the "Heading 3" setting actually the h3 style? Can someone help me out with some CSS code please?

EDIT 12/16:

OK it's not line-height. when I border-up my paragraphs to see where the spaces are, everything zero's out on padding and margin except "Paragraph 3" (the gold Dates). Can anyone help with this extra space?

Thanks, John 

SOLVED. I finally found the object. In my case, there was 16px of bottom margin on p.sqsrte-small which I overrode with 0px

p.sqsrte-small{
  margin:0px;
  padding:0px;
}