<div class="container">

  <p class="box box-1"><code>min(100px, 50%)</code></p>
  <p class="box box-2"><code>max(100px, 50%)</code></p>

</div>
.box-1 {
  width: min(100px, 50%);
}

.box-2 {
  width: max(100px, 50%);
}

/* ETC (Formatting only): */

body {
  margin: 1.5em;
  font-size: 130%;
  font-family: sans-serif;
  background: #f2f0ec;
  color: #2e2c08;
}

.container {
  border: 10px solid #2e2c08;
  background: white;
  padding: 1em;
}

.box {
  padding: 0.5em;
  text-align: center;
  color: #2e2c08;
  background: #e5e3de;
  font-weight: bold;
  margin-top: 0;
  margin-bottom: 0.5rem;
  text-align: center;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.