learn-css-colors-by-building-a-set-of-colored-markers.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Colored Markers</title>
    <link rel="stylesheet" href="styles.css">
  </head>
  <body>
    <h1>CSS Color Markers</h1>
    <div class="container">
      <div class="marker red">
        <div class="cap"></div>
        <div class="sleeve"></div>
      </div>
      <div class="marker green">
        <div class="cap"></div>
        <div class="sleeve"></div>
      </div>
      <div class="marker blue">
        <div class="cap"></div>
        <div class="sleeve"></div>
      </div>
    </div>
  </body>
</html>