Please add div class for content

[lucadealfaro]

We need to display many forms, input etc.
The best way is to create a

that creates the right margins etc, and we can use this all over the place in the app.
And stop using these align="center" things; develop a series of div classes that can be used to wrap all content.
For instance:

• content
• form
• buttons below form
• title?