At ordinary times in the project development, no less margin, location, coordinate what of dealing, the tragedy is that if you are not very clear for these things, the concept of coding will be very painful, when looking for information for precise calculation of distance. The pain...
this is a practical demand, want to get the window scroll, remember is the scrollTop and scrollLeft, results for information to find a very useful diagram.
well, on the drawing finished, I think I need not go into too much detail, later met what client, offset, scroll, including the content of the style of the various margins problem, you don't have to struggle again, take a look at this picture all solved.
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This concludes the body part