The goal here is to develop a simple CSS mechanism to rotate an element yet keep it's content aligned correctly...
This solution is not wothout restriction but the apporeach works.

- this approach introduces an extra orgonizing element .item-set
- .item-set must be of fixed width and height (in this case 100% and 20px)
- combining flipping and rotation is at this point non-trivial

0°:
90°:
180°:
270°:
Flipped horizontally:
Flipped vertically: