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CSS CSS Foundations Values and Units Relative Length Units

Challenge Task 3 question

The challenge is asking me to do the following:

Select the link with the class more. Using the rem unit, set its font size back to the base font size of the root HTML element.

I'm not sure how to accomplish this?

3 Answers

Hi Amanda,

The first question states the browser's default size is 16px. Actually it really doesn't matter how many pixels the default size is. The browser's default size is going to be 1em, or 1rem. Also, the root HTML element is < html > < /html >. While the wording of the question may appear a little vague, I'm sure the intent is to make you think about it.


.more {
  font-size: 1rem;
Youssef S
Youssef S
4,467 Points

The following is from this good read by one of the good folks at CSS-Tricks: Jonathan Snook. Check the article

In respect to the previous correct answer, make sure you understand the difference between em and rem as well: The em unit is relative to the font-size of the parent. The rem unit is relative to the root—or the html—element. That means that we can define a single font size on the html element and define all rem units to be a percentage of that.

Thank you Jeff! I had the 1rem part correct by I was denoting the link the wrong way. Thank you so much for your help.