##  Class files

Sometimes, fonts can appear incorrectly in the built in PDF viewer. If everything is correct in the code, the font should still appear correctly in the downloaded PDF file. To resolve this issue, you can simply change the PDF viewer from built in to native using the instructions found here. If the font is still not OK, there is likely something wrong in your LaTeX. To learn more about how to change typeface in LaTeX, check out our documentation.