Centering images in Bigcartel

on my website here I have an image that is originally 2315 × 3274. What I would like to do is get the image to center on every device, so far I have gotten my image to center on my laptop but when looking at it on my desktop it isn't centered at all. Here is the code

Thanks

#1 .page {
    margin: 0 auto;
}

<p>
<a href="/2"><br>
  <img style="width:100%;margin:0 auto;max-width: 3274px;display:block;margin-right: -150px" src="http://ift.tt/29yfMO8" alt="1"><br>
</a>
</p>