Class Directive

Hi everyone, having a lot of trouble figuring out how to define what
content get's a particular class.

 .. class:: drop-down

    This is a header
    ++++++++++++++++

    I'm a bit of content

    An H2
    =====

So, what I want to do is make the H2 element not have the class "drop-down"
applied to it. I've tried different indentations, etc. The only thing that
seems to work is placing H1 before the h2, this seems to be the only thing
that ends the class. Any help would be appreciated! Thank you!

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