It’s actually a box shadow, and the top and bottom were designed to show both at the same time but more in the direction of the bottom. To fix this you would have to move the shadow back up so it can be even. To do this look around line 728 in your css file or search for this –
`#content .post,
#content .page {
-webkit-box-shadow: 0 3px 6px rgba(0,0,0, .2);
-moz-box-shadow: 0 3px 6px rgba(0, 0, 0, 0.2);
box-shadow: 0 3px 6px rgba(0, 0, 0, 0.2);
background: #fff;
margin: 0 3px 40px;
padding: 20px 0 0;
}`
Then replace that code with this code –
`#content .post,
#content .page {
-webkit-box-shadow: 0 0 6px rgba(0, 0, 0, 0.2);
-moz-box-shadow: 0 0 6px rgba(0, 0, 0, 0.2);
box-shadow: 0 0 6px rgba(0, 0, 0, 0.2);
background: #fff;
margin: 2px 3px 40px;
padding: 20px 0 0;
}`
The code was originally designed for the gray background, but since you changed it to white you would need to do the above suggestion to get it to look right.
Hope that helps, and I hope I didn’t make it sound too confusing.
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