A 500px wide box

A 300px wide box with 200px margin left

a cleared box

A fluid wrapper (gray) contains:

• A wide orange box
• A left float (blue) (here it is an image, but could be anything else)
• A not floated wide box (green), with a wide negative margin-right

The orange box and the negative right margin on the green one together fix the falling of the green box that occurs in IE7-/Win at narrow browser windows.

• The initial page, with the falling box only.
• With a wide box inside the wrapper (it alone, without negative margins, does not fix the problem.)
• With a large negative right margin on the falling box (it alone, without wide box, does not fix correctly the problem: no more dropping, but the the right part of the green box is inaccessible at narrow sizes.)
• With a large negative right margin on a wrapper of the falling box (solves the problem.)

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