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HTML

              
                <main>
  <p>The <a target="_blank" href="https://www.w3.org/TR/css3-values/#em">em</a> unit is interesting.</p>
  <p>It takes the parent's font size and multiplies it by the value you give it.</p>
  <section class="example small-text">
    <p class="em">This text is 2em</p>
    <p class="match">This text is the same as the parent's font size. Which is 10px.</p>
  </section>
  <p>Above, the parent's font size is 10px while the first paragraph's font size is 2em.</p>
  <p>This means the first paragraph's pixel font size is 20px.</p>
  
  <section class="example large-text">
    <p class="em">This text is 2em</p>
    <p class="match">This text is the same as the parent's font size. Which is 20px.</p>
  </section>  
  
  <p>But <code>em</code> can be used outside of sizing text.</p>
  <section class="example large-text">
    <div class="em-width"></div>
  </section>
  <p>The rectangle above has its width set to 3em while its parent has a font size of 20px.</p>
  <p>Making the rectangle's pixel width 60px.</p>
  
  <p>Very cool. ☃️</p>
  <footer class="important">
    <a target="_blank" href="https://xotv.me/channels/22-important/vod_videos/824-important-slash-slash-dribbble-dot-com">!important</a>
  </footer>
</main>
              
            
!

CSS

              
                .em {
  font-size: 2em;
}

.em-width {
  width: 3em;
  height: 10px;
}

.match {
  font-size: 1em;
}

.large-text {
  font-size: 20px;
}

.small-text {
  font-size: 10px;
}

.example {
  margin: 0.5rem auto;
  padding: 0.5rem;
  border: 2px solid #ffe8ec;
  border-radius: 5px;
  text-align: center;
}

.example p {
  margin-top: 0;
  margin-bottom: 0;
}

.example p:last-of-type {
  margin-top: 0.5rem;
}

code {
  padding: 0 5px 2px;
  background-color: #fca67d;
  border-radius: 2px;
  font-family: inherit;
}

div {
  background-color: #ffe8ec;
}

p {
  font-size: 1.1rem;
  font-weight: 500;
  color: #f7f7f7;
}

a {
  font-weight: 900;
  color: #ffe3b0;
  text-decoration-style: dashed;
}

a:hover {
  text-decoration-style: solid;
}

main {
  max-width: 27rem;
  margin: 1rem auto;
  padding: 1rem;
  border-radius: 5px;
  color: white;
  background-color: #ea8071;
}

body {
  padding: 0;
  margin: 0;
  background-color: #e7e7e7;
  font-family: Verdana, Geneva, sans-serif;
}

.important {
  display: block;
  color: #ffc5bc;
  text-align: center;
  transition: all 0.2s ease-in-out;
}

.important:hover {
  animation-name: wiggle;
  animation-duration: 0.5s;
  animation-timing-function: ease-in-out;  
  
  padding: 10px;
  box-shadow: 0 0 4px 1px #d05b4a;
  background-color: #ee897a;
  color: #000;
  text-decoration: none;
  font-size: 1.2rem;
}

@keyframes wiggle {
  0% {
    transform: rotate(0turn);
  }

  25% {
    transform: rotate(0.01turn);
  }

  50% {
    transform: rotate(-0.01turn);
  }

  100% {
    transform: rotate(0turn);
  }
}
              
            
!

JS

              
                
              
            
!
999px

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