index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>GitHub Linguist Free Colour Picker</title>
    <meta charset="utf-8"/>
    <link rel="stylesheet" type="text/css" href="app.css" />
  </head>
  <body>
    <h1>GitHub Linguist Free Colour Picker</h1>
    <p>Use your mouse to find a free colour, or enter a hex value manually.</p>
    <table id="color-picker">
      <tr><td colspan="2"><canvas id="color-block" height="500" width="585"></canvas></td></tr>
      <tr><td id="color-label" style="background-color: white"></td>
          <td><input pattern=".{7}" required id="color-input" type="text" value="#"/></td></tr>
    </table>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/js-yaml/3.10.0/js-yaml.min.js"></script>
    <script src="colour.js"></script>
    <script src="app.js"></script>
  </body>