Twitter Bootstrap 3.1.1 integration starting with the code form
Styling of error message
Styling of code input form
removed obselete heading definition
moved h1 into div.content to align it with the content
removed underlined style, as it may be mistaken as a link and makes the text less readable.
Styling of 'Zu den Uebungsaufgaben'-link
Styling/text contents of instructions box on input keys
Replaced .bold CSS class with strong tags for better semantics
Reduced size of keyboard image in instructions
Style and textual improvements
Styling of blood tubes and tube boxes, making the tube box image obselete
Smaller verions of blood tubes and tube boxes on the instructions page
Styling of locked keys
Styling of dry rund end card