Re: diagonal line

[Rob Wierzbowski]

If you’re ok with a css3 requirement, you can create an oversized image with a diagonal line from one corner to the other, and then apply as a fixed background on an element with [background size](https://developer.mozilla.org/en-US/docs/CSS/background-size): 100% 100%. One quibble is the line thickness will change depending on the pixel size of the viewport, but during a single session that won’t be noticeable.