FAQ: Changing the Box Model - Review: Changing the Box Model


This community-built FAQ covers the “Review: Changing the Box Model” exercise from the lesson “Changing the Box Model”.

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Is it only the universal selector that the border-box can be applied to?


That box-sizing value can be applied to any element to which a border can be applied. That means all block level elements.

What’s more, it is not very judicious to use the universal selector at all given the amount of resources expended. It selects everything in the HTMLElement group and writes the rule for each node type, regardless whether it exists in the document or not. Better to write selector rules for elements that actually exist. The universal selector is not a silver bullet, but an expensive hotel bill.

* {
  box-sizing: border-box;

IMHO, this is so not right, but there would not be this selector if there wasn’t a valid use for it. Let your studies reveal it, and learn to use it wisely, or never.