<div class="color-list">
 
  <section class="color" style="background: hsl(4,99%,66%);">
    <h2 class="name">Persimmon</h2>
    <ul class="details">
      <li>hsl(4,99%,66%)</li>
      <li>#FE5E52</li>
      <li>178 C</li>
      <li>485 U</li>
      <li>Primary</li>
    </ul>
  </section>

  <section class="color" style="background: hsl(233,21%,56%);">
    <h2 class="name">Kimberly</h2>
    <ul class="details">
      <li>hsl(233,21%,56%)</li>
      <li>#777DA6</li>
      <li>7675 C</li>
      <li>7669 U</li>
      <li>Primary</li>
    </ul>
  </section>
  
  <section class="color" style="background: hsl(357,26%,42%);">
    <h2 class="name">Au Chico</h2>
    <ul class="details">
      <li>hsl(357,26%,42%)</li>
      <li>#874F52</li>
      <li>4985 C</li>
      <li>188 U</li>
      <li>Secondary</li>
    </ul>
  </section>
  <section class="color" style="background: hsl(144,33%,68%);">
    <h2 class="name">Shade Green</h2>
    <ul class="details">
      <li>hsl(144,33%,68%)</li>
      <li>#92C8A8</li>
      <li>345 C</li>
      <li>344 U</li>
      <li>Secondary</li>
    </ul>
  </section>

  <section class="color" style="background: hsl(97,62%,80%);">
    <h2 class="name">Tea Green</h2>
    <ul class="details">
      <li>hsl(97,62%,80%)</li>
      <li>#C5ECAC</li>
      <li>7486 C</li>
      <li>7486 U</li>
      <li>Secondary</li>
    </ul>
  </section>
</div>
body {
  font-family: 'Open Sans', sans-serif;
}

* {
  /* Ensure sane sizing of all elements */
  box-sizing: border-box; 
}

.color-list {
  display: flex;
  /* 
    On small displays we want each .color stacked.
    Flexbox let's us determine stacking direction via
    flex-direction: column;
  */
  flex-direction: column;
  height: 100vh;
}

.color {
  /*
    Each .color is also a flex item. We do this so that we have reasonable
    distribution of space between elements. We use flex-direction so that
    flexbox knows which way to position each element (in this case, vertical).
  */
  display: flex;
  flex-direction: column;
  
  /*
    .color can grow but not shrink (we want space for first three elements).
    10em is enough space to see name, hsl, and hex values. 
    Try shrinking vertically on a small display.
  */
  flex: 1 0 10em;  
  box-shadow: 0 0 30px #424242;
  
  /* Handles any clipping/overflow issues on transition */
  overflow: hidden;
  padding: 1em;
  color: white;
  transition: flex-basis 500ms ease-in-out;
}

.color:hover {
  /*
    Change the flex-basis so that we know what
    size to transition to on hover. Arbitrary,
    based on our design/content.
  */
  flex-basis: 20em;
}

.color:hover .details {
  opacity: 1;
}

.name {
  font-size: 1.2em;
  font-weight: 600;
}

.details {
  margin: 0;
  padding: 0;
  list-style: none;
  opacity: 0;
  transition: opacity 500ms ease-in-out;
}

.details li {
  font-size: 1em;
  line-height: 2em;
}

@media (min-width: 600px) {
  .color-list {
    /*
      Change the direction so that each .color
      aligns horizontally
    */
    flex-direction: row;
  }
  
  .color {
    /*
      No scrollbars on mobile
    */
    flex-shrink: 1;
  }
}

/* Fonts, OK at the end for this demo! */
@import url(https://fonts.googleapis.com/css?family=Source+Sans+Pro:400,600);
/* 
COLOR PALETTE
Flexbox Fridays Week 2 brought to you by team Lincoln Loop 
https://lincolnloop.com/

Inspired by this pen:
https://codepen.io/Nyloxz/pen/Bqpdh

Thanks app.coolors.co for being so awesome! 
*/

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.