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Ems vs. Pixels on Margin and Padding

In my layout, I stuck with ems instead of px to define margin and padding throughout. For example, on .banner, I have margin-bottom: 1.8em as opposed to margin-bottom: 60px like Guil has.

For responsive behavior, shouldn't we use ems as much as possible? I suppose, visually, the results seem to be comparable, so perhaps it just preference.

In retrospect, ems are just a way to convert to px, usually with 1em = 16px. So, changing the 'base' away from 16px could make using ems good or bad, since all of our margins/padding will 'auto adjust.'

So, I guess, it really doesn't matter too much after all...

1 Answer

It does matter. Use em and vw units. em units have an exact proportional relationship to each other which makes em values amazing. Here is a good blog post about using ems:

em units

I hope this helps.

Yes, thank you for the link. I liked the example of making a 'font' resizer using 'small' and then %. Of course, one can probably use Sass for that now; that is, have an 'easily defined' variable in 1 place to change and affect the whole site.

It sounds like cascading might be troublesome for ems, so will watch for this.

Not a problem. yeah CSS Tricks is full of really useful articles. I'm glad it helped.