Instead of styling every elements focus individually, a singular element will indicate the current document focus. The transitional animation helps users follow the focus.
A clearly visible focus rectangle will show up and animate to the next focusable element. This helps a lot following the currently focused element. And it's actually much more accessible than the standard focus rings due to high contrasts.
Visual users rather don't bother with the current focus (they're focus is where the mouse or finger points), which is why we hide the flying focus as soon as we notice any such user input.
Use the tab keys to focus Links or or