/* Some example CSS */

@import url("something.css");

body {
  margin: 0;
  padding: 3em 6em;
  font-family: tahoma, arial, sans-serif;
  color: #000;
}
.CodeMirror-linenumber {
    padding: 0 3px 0 5px;
    min-width: 20px;
    text-align: right;
    color: #999;
    white-space: nowrap;
}
<script>
require([
  "cm/lib/codemirror", "cm/mode/htmlmixed/htmlmixed"
], function(CodeMirror) {
  CodeMirror.fromTextArea(document.getElementById("code"), {
    lineNumbers: true,
    mode: "htmlmixed"
  });
});
</script>
<script src="lib/codemirror.js"></script>
<link rel="stylesheet" href="lib/codemirror.css">
<script src="mode/javascript/javascript.js"></script>
require([
  "cm/lib/codemirror", "cm/mode/htmlmixed/htmlmixed"
], function(CodeMirror) {
  CodeMirror.fromTextArea(document.getElementById("code"), {
    lineNumbers: true,
    mode: "htmlmixed"
  });
});