Structure, keyboard, and focus
Protect focus order and visibility
Keep DOM order logical, focus indicators visible, and off-screen or hidden content out of the sequence.
9 minute lesson
The visual card layout follows the same DOM order, and sticky content does not cover the focused element. That contrast gives us something useful to test instead of a rule to memorize.
Focus order should follow the task, while a visible indicator shows exactly where keyboard input will go. The useful target is not encyclopedic coverage. Make one deliberate choice, observe its consequences, and know which requirement would make you revise it.
The happy path can hide a bad design: you can repair layout with positive tabindex values or remove outlines without an equivalent and still get one successful demo. Push past the demo. keep source order meaningful, use natural focus, and style a high-contrast indicator that remains unobscured, then test the condition most likely to prove the choice wrong.
The module is moving toward one outcome: Make page structure and every interaction understandable and operable without a mouse. Save the before-and-after evidence now; it will make the final project review much more honest.
Tab at 200 percent zoom and in high-contrast settings; capture every place focus becomes hidden or surprising. Save the evidence, then explain which requirement would force you to choose a different design.
Lesson completed