Here's a list of themes that you can use to change the apperance of the image pooped out by copper.
- default
- agate
- androidstudio
- arduino-light
- arta
- ascetic
- atelier-cave-dark
- atelier-cave-light
- atelier-dune-dark
- atelier-dune-light
- atelier-estuary-dark
- atelier-estuary-light
- atelier-forest-dark
- atelier-forest-light
- atelier-heath-dark
- atelier-heath-light
- atelier-lakeside-dark
- atelier-lakeside-light
- atelier-plateau-dark
- atelier-plateau-light
- atelier-savanna-dark
- atelier-savanna-light
- atelier-seaside-dark
- atelier-seaside-light
- atelier-sulphurpool-dark
- atelier-sulphurpool-light
- atom-one-dark
- atom-one-light
- brown-paper
- codepen-embed
- color-brewer
- darcula
- dark
- darkula
- docco
- dracula
- far
- foundation
- github-gist
- github
- googlecode
- grayscale
- gruvbox-dark
- gruvbox-light
- hopscotch
- hybrid
- idea
- ir-black
- kimbie-dark
- kimbie-light
- magula
- mono-blue
- monokai-sublime
- monokai
- obsidian
- ocean
- paraiso-dark
- paraiso-light
- pojoaque
- purebasic
- qtcreator-dark
- qtcreator-light
- railscasts
- rainbow
- school-book
- solarized-dark
- solarized-light
- sunburst
- tomorrow-night-blue
- tomorrow-night-bright
- tomorrow-night-eighties
- tomorrow-night
- tomorrow
- vs
- xcode
- xt-256
- zenburn"