Login as Demo and use the usertheme_menu to switch between 100% wide and fixed page size.

Demo Login:
Username: demo
Password: demo

Theme version: 1.0

Other e107 theme details

1000px fixed width or 100% browser wide (configurable in theme.php)
Drop down links width 4 sub levels
100% XHTML
Web 2.0 oriented

You can setup 4 layouts - just use the visibility option of each menu and the theme will fit automatically:
1 Column - Center column (Hide all menus)
2 Columns - Left and Center column (Hide right column)
2 Columns - Right and Center column (Hide left column)
3 Columns - Left, Right and Center column

Enjoy!

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