Change Github's Default Gist Styles

Question

Is it possible to change Github's gists default styles programmatically or through some interface?

Answer 1

I don't know of any API or interface influencing the way gist are presented on GitHub.

If you include those gist in your blog, then of course some CSS local changes can make your gist different, as illustrated by this blog post, this CSS or this CSS.

However, this doesn't concern syntax highlighting.
You can only share those Gist with a custom stylesheet through, for instance Octopress, using a Sass port of Solarized syntax highlighting.
But again, that won't change those gist presentation on GitHub itself.