Show div when link is clicked below

Show div when link is clicked below

I need a way to create a dropdown. That shows a table above when a link is
clicked below.
My HTML
<div id="container">
<table id="supposeToBeHidden">
some content
</table>
<a href="#" id="btnToClickToShowTable">Click me</a>
</div>
It would be cool if the solution was in pure css, but not a must.