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CSS CSS Basics (2014) Understanding Values and Units Rem Units

Posted by hassan mohammad
hassan mohammad
Courses Plus Student 818 Points

Difference between px , em and rem

I still dont know whats the difference

1 Answer

Jamie Reardon
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Jamie Reardon
Treehouse Project Reviewer
Jamie Reardon
.a{fill-rule:evenodd;}techdegree seal-36
Jamie Reardon
Treehouse Project Reviewer

Px is a fixed unit which means that it always stays fixed at that size. You would use pixels when you want precise sizing.

Em and rem are relative units, which means that they are always relative to a font size. They are basically multipliers.

The difference between em and rem is that em is always relative to the parent element, rem is always relative to the root element (html). Typically, 1 em is equal to the default font size of 16px.

hassan mohammad
hassan mohammad
Courses Plus Student 818 Points

Thanks