CSS Absolute Positioning of one div being affected by margin in unrelated div
问题 Given the following I would expect a 200px red box at the top of the page followed by a white space of 100 pixels then a purple box on the bottom. This is what the WYSIWYG view in Dreamwever shows me but what I get in FF IE Chr is a red box in the middle of the page. Funny thing is if I add a border to the wrapper div I get what I expect. So what is happening is that the margin-top:300px of the #content div is pushing down the #header div. Since the #header div is positioned absolutely inside