Disallow units for 0 values

Rule from css under compatibility category

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You shouldn't specify any units after a 0 value. So in other words do not:

/* BAD: */
.box {
  margin: 0px;
  padding: 0em;
  border: 1px solid black;

This might be a bit pedantic but the CSS spec allows for no units after 0 values as it's redundant. Leaving them out will save bytes and saving bytes is good.

How do I fix this ?

Just remove all unit specifics after 0 such as 0px, 0em and 0%.

/* GOOD: */
.box {
  margin: 0;
  padding: 0;
  border: 1px solid black;


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