Okay, I've got seven or so pages mocked up with header div, nav div and then a content div. the body tag has a max width of 960px and auto left & right (so centered on the page).
On all the pages so far, they all line up sweet.
On one, when I paste some text (roughly an A4 page worth) into the content div, the whole page shifts to the left by about 10 pixels. Header div, nav div and content div.
The text is just plain, unstyled text with no CSS applied.
It's doing my head in - that particular page 'jumps' to the left, whereas all the other pages are perfect.
The page shift to the left is caused by the appearance of the vertical browser scroll bar on pages where the content is more than a screen deep (therefore requiring scrolling).
Where the content is less than a screenful, the scrollbar disappears and the page shifts to the right.
The usual fix is to add the following rule to your CSS stylesheet
This forces a scrollbar to appear on every page (thereby eliminating the page shift) whether it is required by the amount of content or not.