basic css positioning question with margins and ul

This is a very basic question. I'm so confused as to why my button saveBtn is not center aligned an开发者_运维问答d it is for some reason floating on top of my ul. any help would be appreciated. I'm just trying to understand css positioning more because to me if I set a margin-top of 20px it should be 20px under the previous div?

http://jsfiddle.net/dasaki/3PujE/

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delete the position:absolute under #infoBox and #saveBtn, that will make the savbutton in the right place, not floating on top of the ul section

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as Zhang Yu said..

here is it with the changes

http://jsfiddle.net/3PujE/3/

looks like you should mess around with basic css positioning so you can understand it better