Simon, thanks for the great tip, you hit the nail on the head.
I have made changes to the way font-size is determined in the CSS (style sheet); now it uses units of "%" instead of "EM". Although both are relative size specifications, it seems that "EM" units aren't happy when the browswer's text size is set to anything other than medium.
Bottom line: the site should now work for everyone, without having to change your font display properties.
Thanks for your patience, everyone. If you have any more problems, please let me know ASAP!
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