Cant align image in center

How to center the Jewellery Sets Image ? I cant use margins as the space would change for different resolutions, suggest some fix ? I tried every possible suggestion on google, nothing worked.

heres the link = http://jewelandjewellery.com/wp/

Currently i am using the following code for the middle image –

<img src = “xxxxx” style=”margin-left:auto;margin-right:auto;” width:265px;display:block” >

Img alignment right and left works fine but image align=middle doesnt work.

Plz Help