You want enabling CSS selectors, not disabling ones

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Chris Coyier on (Updated on )

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I think this is good advice from Silvestar Bistrović:

An enabling selector is what I call a selector that does a job without disabling the particular rule.

The classic example is applying margin to everything, only to have to remove it from the final element because it adds space in a place you don’t want.

.card {
  margin-bottom: 1rem;
}

/* Wait but not on the last one!! */
.parent-of-cards :last-child {
  margin-bottom: 0;
}

You might also do…

/* "Disabling" rule */
.card:last-child {
  margin-bottom: 0;
}

But that’s maybe not as contextual as selecting from the parent.

Another variation is:

.card:not(:last-child) {
  margin-bottom: 1rem;
}

That’s what Silvestar refers to as “enabling” because you’re only ever applying this rule — not applying it and then removing it with another selector later. I agree that’s harder to understand and error-prone.

Yet another example is a scoped version of Lobotomized Owls:

/* Only space them out if they stack */
.card + .card {
  margin-top: 1rem;
}

I think gap is where this is all headed in the long term. Put the onus on the parent, not the child, and keep it an enabling selector:

.parent-of-cards {
  display: grid;
  gap: 1rem;
}

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