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CSS

Posted by Katherine Hammitt
Katherine Hammitt
1,201 Points

Where can I find more information on em/rem use versus pixels?

Where can I find more information on em/rem use versus pixels? I have completed the CSS basics course but I still am not fully grasping this concept. I understand that it is a relative unit based on the parent element.... is the parent element defined in px or em?

1 Answer

Patrik Horváth
Patrik Horváth
11,110 Points
Patrik Horváth
Patrik Horváth
11,110 Points

Hi, so "em" are good if you want do math or remember every parent element size ..., "rem" with combination ROOT property in css you can setup 1rem = 10px for example or 1 rem = 1px

Root info : https://developer.mozilla.org/en-US/docs/Web/CSS/:root

for me use REM always ( em = OLD , rem = NEW )

Katherine Hammitt
Katherine Hammitt
1,201 Points

Why would you use rem over px? Why do the math at all? Is it so you only have to change the parent element to change everything?