discurso is a theme by codematurgy, responsive to a smaller screen size and featuring a good chunk of options:
show or hide your header on the mobile version(not available for desktop version!)
choose if you’d rather upload your own sidebar image, use your header(which makes you load less images) or use no sidebar image at all
choose if you’d like to show your avatar on desktop(it will always show on mobile version)
pick between three margin sizes
pick between three sidebar widths
pick between three font sizes
hide or show captions on index
hide or show tags on index
hide or show search bar
pick between light or dark background posts
pick between light or dark font for links over accent colors
insert post size(maximum size is 700)
credits go to:
photosets by PixelUnion
captions and other tumblr variables by bychloethemes
customised like button by mikedidthis on Stack Overflow
you can see a preview of the theme here, while you can grab the code on Pastebin. if you wish for a version that does not synchronize with your tumblr colors, you can check this Pastebin link instead.