Here are some CSS rules being applied to this page:

      h6 { font-size:110%; }
      h5 { font-size:130%; }
      h4 { font-size:150%; }
      h3 { font-size:170%; }
      h2 { font-size:190%; }
      h1 { font-size:210%; }
      p  { font-size:12pt; }

Here is the result:


Heading 1

Heading 2

Heading 3

Heading 4

Heading 5
Heading 6

Paragraph text