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The calc() function lets you perform basic math operations on values, and it’s especially useful when you need to add or subtract a length value from a percentage.
This is how it works:
div {
max-width: calc(80% - 100px)
}
It returns a length value, so it can be used anywhere you expect a pixel value.
You can perform
- additions using
+ - subtractions using
- - multiplication using
* - division using
/
One caveat: with addition and subtraction, the space around the operator is mandatory, otherwise it does not work as expected.
Examples:
div {
max-width: calc(50% / 3)
}
div {
max-width: calc(50% + 3px)
}