Thanks to Tom, Jeremy and Josh for their attempts at this, which helped set me on the right track. I got close enough with a result that I'm happy — I'll be keeping an eye on this thread, though, just in case someone comes up with something better.

In short, I have a 100%-wide wrapping div in which I'm positioning the image absolutely on the lefthand side within a div that's 70vw. Then, there's a psuedo element in a parent div that draws overtop the image where the sidebar starts; because this psuedo element is created on the parent div, it's the same percentage width as the sidebar itself, so it always matches.

I'm not sharing code because it's not quite perfect. When it is, I'll update this. But it's good enough for now.

I'm hoping to be able to put content across the width of the box-breaking element; specifically, an image.

I like where this is headed. Any way to make this work a little better if the container (.wrapper in yours) has a max width in px?

Thanks for trying, but this isn't anchored to the right edge of the main column.

Sorry about the ill-formatted image. DN doesn't have preview or edit.

Great idea, and sorely needed. I wish I could pick a custom colour for my monogram. Also, it'd be great if standardresume.io/user would redirect to rsm.io/user, just in case people type in the wrong address.