Mayra, esto es lo grupo web2py en ingles.
Por favor, reecriba tu question en ingles para que qualquier uno pueda compreenderla.
Asi tenes mas chances de ser respondida.
Mayra, this is the web2py group in english.
Please, rewrite your question in english so anyone can understand it.
So you more chances to be answered.
The default layout.html already fits well and resizes itself when displayed and smaller devices.
You can teste this by simpling resizing your browser window.
For me, it looks like you have a issue with your own css styling.
Maybe you need to redesign it avoiding fixed widths and heights.
Also give a look at the Bootstrap documentation, it is the css (and other things) framework used now in Web2py.
Look how you can design your layout safely across different devices using the appropriated classes.