ne-numbers, line-highlighting and themes are limited at present.

Include line numbers:

      <prism-js language="javascript" linenumbers="true">
          if (true) {
              console.log('foo');
          }
      </prism-js>

Specify a language and theme:

      <prism-js language="css" theme="okaidia">
          p { color: blue; }
      </prism-js>

  Line-highlighting:

      <prism-js language="css" linehighlight="5"></prism-js>

  Line numbers with line-highlighting:

      <prism-js language="c