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CSS CSS Basics (2014) Understanding Values and Units Em and Rem Units

Posted by Taryn Trueblood
Taryn Trueblood
21,798 Points

What is the em equivalent to 20px?

I computed the 20px to em like in the lesson but I continue to get "is the font-size of h3 em equivalent to 20px" I don't know what I am doing wrong?

style.css 
/* Complete the challenge by writing CSS below */

header {
  font-size: 1.8em;
}

.title {
  font-size: 1.625rem;
}

h1 {
  font-size: 5.625rem;
}

h2 {
  font-size: 3.3125em;
}

h3 {
  font-size: 1em;
}
index.html 
<!DOCTYPE html>
<html>
  <head>
    <title>Lake Tahoe</title>
    <link rel="stylesheet" href="page.css">
    <link rel="stylesheet" href="style.css">
  </head>
  <body>
    <header>
      <span class="title">Journey through the Sierra Nevada Mountains</span>
      <h1>Lake Tahoe, California</h1>
    </header>
    <div class="main-content">
      <p>
        Lake Tahoe is one of the most breathtaking attractions located in California. It's home to a number of ski resorts, summer outdoor recreation, and tourist attractions. Snow and skiing are a significant part of the area's reputation.
      </p>
      <a href="#">Find out more</a>
      <h2>Check out all the Wildlife</h2>
      <p>
        As spawning season approaches, the fish acquire a humpback and protuberant jaw. After spawning, they die and their carcasses provide a feast for gatherings of mink, bears, and Bald eagles.
      </p>
      <a href="#">See the Wildlife</a>
      <h3>From Tents to Resorts</h3>
      <p>
        Lake Tahoe is full of wonderful places to stay. You have the ability to sleep in the outdoors in a tent, or relax like a king at a five star resort. Here are our top three resorts:
      </p>
    </div>
    <footer>
      <p>All rights reserved to the state of <a href="#">California</a>.</p>
      <a href="#top">Back to top &raquo;</a>
    </footer>
  </body>
</html>

3 Answers

Wayne Priestley
Wayne Priestley
19,579 Points
Wayne Priestley
Wayne Priestley
19,579 Points

Hi Taryn,

20px ÷ 16px = 1.25

20px is your target and 16px is the base size of the font.

Hope this helps.

John Nguyen
John Nguyen
6,227 Points
John Nguyen
John Nguyen
6,227 Points

Here's a useful website tool to help you with your conversions: http://pxtoem.com/

By default the base font size is 16px, but if you assign a new font size - such as 18px or 22px- then that becomes to new base size (ie. 1em), and all of unit sizes using em will be multiples of the base size.

For example:

h3 {font-size: 1.2em; } // In pixels, this is 19px

html { font-size: 18px; } // Define a new base, 1em

h2 {font-size: 1.2em; } // In pixels, this is 21px

Mikael Enarsson
Mikael Enarsson
7,056 Points
Mikael Enarsson
Mikael Enarsson
7,056 Points

The key here seems to be the part of the question reading "Using the same parent font-size context." That parents font-size was 16px, btw.