Here are a few tips I’ve gathered up to help you write a more efficient or clutter-free CSS.

No units for Zero values

.mybox {
    margin-top: 0px;
}

This I’ve seen oh so many times! Sure the CSS validator won’t give you an error because of it but when you think about it, why put units? 0 is still 0 in px, pt, em, %, etc…
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