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I am tweaking the look of Gnome Shell and was asking my self what the following, and also specifically what "ems" means in gnome-shell.css

/* The remaining popup-menu sizing is all done in ems, so that if you
* override .popup-menu.font-size, everything else will scale with it.

Would somebody explain it to me? I prefear to not break anything if possible, so thats why I am asking.

Thanks in advance! Roberto

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An em is the width of the character M. Well, that's the etymological reason, anyway. It is a measurement of size in relation to your font size. Gnome Shell uses CSS, which is the same language that most all webpages use. This means there are buckets of places to find information about how it's used. This link has examples, for example (:

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Thanks Jo for your answer, I will look into that – Roberto Giardina Nov 11 '11 at 11:42
Actually I still dont understand the statement above, apart from what "ems" is; If I search for a line containing ".popup-menu.font-size" I can't finde one. Instead I find many lines containing either "popup-menu" or "font-size". Now, if I do correctly understand, if I change (override) the value of a certain line (.popup-menu.font-size) everything else (just what concerns the popup-menu?) will scale? That would simplify the work. But where exactly do I have to change a value? Cause as stated I cant find a line containing ".popup-menu.font-size" Thanks for you help, Roberto – Roberto Giardina Nov 11 '11 at 11:59

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