You can do this, for example. have a different background color for the final slide:
Declare a style for the background (given the end class):
html.the-end .state-background { background-color: rgba(0,0,0, 0.8); }
Then the final slide looks like this:
<section data-state='the-end'> <h1>__END__</h1> <br> <h3>Thank you!</h3> </section>
EDIT (added tyler rinker) . You are right, but I wanted to be more explicit for future search engines. I added the following two segments.
Added this to display .min.css
.orange .reveal .state-background{background:rgba(255,165,0,1)}
Added this to display .css
.orange .reveal .state-background { background: rgba( 255, 165, 0, 1 ); }
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