There is no html code to change the font-face of text on this game (including HEE and DT). You can play around with the size of the text or change it to coded, italicized, quoted, centered, or strong/bolded text.

You can also look up funky or foreign symbols/letters online and copy and paste them. Warning: depending on the device someone uses, some funky texts may not be visible and your writing is just going to look like broken squares.