css - How do i Center this Simple Slideshow? -

I am trying to bring this slide show to the center without success:

It looks like is the situation: absolute which is actually messing with me ...

How do I focus this slide show so that the page's Change the shape, it looks correct, and the slideshow still works correctly?

Please help!

status: full like this:

 < Code> .elem {status: absolute; Width: 200px; Height: 200px; Left: 50%; Margin-left: -100px; / * You can reduce the width by halfway margin byte * /}