Utilities to warkaround calc() limits

[SergeVDev]

Hi folks,

There are lots of questions on Stack Overflow, how to do something in pure CSS that can't be achieved due to calc() limits.

To give you just one example, https://stackoverflow.com/questions/38617025/using-n-inside-calc (Duplicates: https://stackoverflow.com/questions/28002684/is-there-a-way-to-use-the-n-value-in-nth-childn, https://stackoverflow.com/questions/42434460/index-of-nth-child-within-the-css-rule and so on, hundreds of votes in total).

What if create utility classes to workaround this? For instance, after adding indexed class to an element you would get a variable --item-index (or similar named) for each child of the element, that could be used in calc(). Implementation is trivial, but it seems to be in demand.

Another example: https://stackoverflow.com/questions/8720931/can-css-detect-the-number-of-children-an-element-has (383 votes). After adding a class, say, count-children, BS could set a variable --children-number to use within calc().

Sorry, if the idea doesn't belong to Bootstrap domain.

Regards,