SClass"><h3 id="buildCSSClassHeader">buildCSSClass()</h3><div id="buildCSSClassDescription" class="description"><p>Allow sub components to stack CSS class names</p></div><p class="vjs-only"><em id="buildCSSClassFooter">Defined in <a href="https://github.com/videojs/video.js/blob/master/src/js/popup/popup-button.js#L69">https://github.com/videojs/video.js/blob/master/src/js/popup/popup-button.js line number: 69</a></em></p><p><a href="#top">[back to top]</a></p></div><div id="MethodscreateEl"><h3 id="createE