On the example site https://edwardtufte.github.io/tufte-css/ if you have a narrow window and a slightly increased font size you trigger the mobile layout. Unfortunately this renders some of the content inaccessible to keyboard users.
The issue looks to be caused by a checkbox with display = none. A potential fix would be to stack the label and check box and reduce the visibility.
On the example site https://edwardtufte.github.io/tufte-css/ if you have a narrow window and a slightly increased font size you trigger the mobile layout. Unfortunately this renders some of the content inaccessible to keyboard users.
The issue looks to be caused by a checkbox with display = none. A potential fix would be to stack the label and check box and reduce the visibility.