That's not the real problem.
The problem is that the foother has this background:
background: #5a5a5a;That is the grey "line" you see.
And the footer is bigger than the colophon in which you have the texture background.
Try to set the foother height to 50px and then the wrap div margin-bottom to -62px
.
Anyway thanks for pointing this, I will think at a better solution for the sticky footer snippet