Let's try the sledgehammer approach. I suppose it's possible to have an aggressive cache.

1) Open http://calamnet.github.io//theme.css

2) Load that up and hit ctrl+f5.

You should see the following code at the top. The text-align:center; line is what I added in an attempt to fix the chrome issue.

body {
color: #fff;
font-family: Arial, Helvetica, sans-serif;
background-color: #2d1312;
background-image: url(./images/background.jpg);
background-repeat: no-repeat;
background-size: cover;font-size: 14px;
text-align: center;
margin: 0;
padding: 0;
}

3) Reload Utopia

I'm tempted at this point to refork it into a new project entirely.