Recently seen three-column layout, to find that the margin-left: -100%; do not quite understand what this record
margin-left: -100%; what does it mean? Meaning that the moving distance of the entire screen to the left
However, writing in a three-column (one) is inside the box may be moved to the dark areas on the map, this is the reason:
Black region and a blue region are added to the float, a negative percentage when the margin-left again on the relative box is actually a floating box
Summary: The layout can be achieved with the float and negative percentage margin-left, margin-left simply can not be done