We applied the theme and inspected the real root menu. The selected Apps row is readable but its 8 percent fill is too subtle for this tutorial. Make that selection more obvious: increase selected-background-alpha from 0.08 to 0.16 in the menu and launcher overrides while keeping ink text. Change nothing else, update the validation/README, show the two-line diff and recompute selected-row contrast. Do not apply it; I will record the reapply.