Look at the narrow hr bar ... very left edge has a 1 pixel artifact that is caused ( I think ) by the border-top. Change the border-top: to border: and the artifact goes away. Doing that may break something somewhere else though .. IDK. Hard to see the artifact on the attachment so you will likely need to look at a working site.
index_light.css
hr {
border-top: 1px solid #bbb;
background: #eee;
background-color: #eee;
}Does not seem like much but it is guaranteed that users will notice this and bring it up.
Another browser-dependant result... :-\
I tried using border and: with firefox the pixel goes away, while with Chrome and it creates a small box around a 1px area (that is actually correct because the hr has a height of 1px).
Can you try using:
border-left: 0;
seems to disappear as well.
Seems to work for me ... I added it to a PR I have pending since its certainly better than whats there.