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CSS How to Make a Website Customizing Colors and Fonts Resize Text

Ben Brenton
Ben Brenton
266 Points
Posted by Ben Brenton
Ben Brenton
266 Points

em vs px for multi-platform use

For a project which is to be used on computer, tablets, phones etc., surely em is better to use as it adjusts with the screen it is on, rather than pixel, which is more defined? Is this correct, and which would I be better using? Also, if this is indeed a correct way of looking at it, why would you use both values in your CSS? Surely you would go with one or the other?

1 Answer

Thas Eagans
PLUS
Thas Eagans
Courses Plus Student 2,533 Points
Thas Eagans
Thas Eagans
Courses Plus Student 2,533 Points

Em is relative, whereas PX kind of locks you into a fixed measurement. What I sometimes do is use PX in a fluid design when i want the spacing or margin to remain fixed regardless of what size screen its on. For instance.... I want div 1 to have a 20px top margin from div 2.

I actually prefer to use rem instead of em. Em is based on its parent element, whereas rem is based on the root element. This prevents some unnecessary headaches if a parent container changes it's font size.

</TREagans>

Ben Brenton
Ben Brenton
266 Points
Ben Brenton
Ben Brenton
266 Points

Thank you for clearing that up for me!