These are the copyrighted materials I should mention about.

"3 the Hard Way Rmx" font
copyright © Fenotypefaces 2002, Emil Bertell

"Visitor TT2" font
copyright © Brian Kent

"Cadenas" padlock icon
copyright © Sebastien Durel, licensed under CC BY 3.0

"Flock Wallpaper Pattern"
copyright © Hydrogen666, licensed under CC BY-SA 3.0

Game icons
copyright © by their authors and right owners

highlight.js
copyright © 2006, Ivan Sagalaev