This is an example how I do it now and works fine on any computer just not tablets.
<data name="htmlGreen" devices="desktop|tablet|mobile">
<img src="indexdata/img/portraitGreen.png" style="padding:8px;" width="600px" height="300px" />
<p align="right">
<a href="event:action(loadpanoGreen); stopallsounds(); playsound(HallSoundGreen, greenBackgroundSound.mp3, 0, 0);">
<font color="#359c3e" face="verdana" size="36px" style="font-family:verdana; font-size:36px;">
YES
</font>
</a>
<a href="event:action(hidewindow,htmlGreen); stopallsounds(); playsound(HallSound, hallBackgroundSound.mp3, 0, 0);">
<font color="#359c3e" face="verdana" size="36px" style="font-family:verdana; font-size:36px;">
NO
</font>
</a>
</p>
</data>
<data name="cssGreen">
a { text-decoration:none; color:#359c3e; font-weight:bold; }
a:hover { color:#cccccc; }
</data>