chappie on "[Theme: Customizr] Text rollover = image popup"

I'm trying to get some inline text to generate a popup image on rollover. A knowledgeable person in another place has suggested that the built-in dropdown menu class can be tweaked to work this miracle. His code:

<div id="access">
<ul class="menu"><li class="menu-item">Spoiler
<ul class="sub-menu">
<li class="menu-item">SPOILER TEXT HERE</li>
</ul>
</li>
</ul>
</div>

Could someone please tell me the equivalent Customizr classes to target -- if this looks like it might work?

There is an example of exactly what I want (albeit applied to a p rather than inline text) at the bottom of his blog (red word "Her") at:
http://wpbtips.wordpress.com/2013/03/16/spoiler-hover-content/

Many thanks.