Style titled and untitled posts differently?

Hi! I was wondering if there’s a way to style titled and untitled posts differently, for example, to achieve a mix of normal blog posts and microblog posts.

In that scenario, if I post a long text with title everything remains as in the default setting, I.e., post title is show with the date below it and the rest of the text following, wrapped up by the tags, if any. But if I post something untitled, be it a single paragraph or a sole picture, then the date, instead of showing on top, moves to after the content and is displayed smaller.

Is there any way this effect could be achieved?