Reproduce navigation overflow with long and translated labels, repair nested flex and text constraints, and verify reflow and keyboard access.
Test visible keyboard focus on a link, input and working button, and distinguish focus-visible from hover and pointer focus.
Build a complete main-and-sidebar layout, reproduce long-content overflow, and verify track widths, the mobile breakpoint and keyboard access.
Choose a breakpoint by testing real card content, compare 719px with 720px and distinguish CSS viewport width from device resolution.
Anchor badges to separate cards, inspect their containing block and distinguish a visual relative offset from normal-flow spacing.
Compare natural sizing, cover and contain with one downloadable test image. Measure the result and choose cropping deliberately without stretching the artwork.
Reproduce an anchor hidden beneath a sticky header and keep a measured scroll offset correct when the header wraps.
Build and test a local email validation flow that explains errors, preserves the typed value and clears stale error states after correction.
Migrate a button to shared brand tokens, override one section, and check hover, keyboard focus and fallback behaviour in a complete local example.
Reproduce a nested-container breakpoint failure, select the intended named ancestor, and verify the repair at a fixed viewport and at its boundary.
Put an old stylesheet in the first layer so your new rules win without touching the old file or raising specificity.
Keep spinners and fades, replace slides and smooth scrolling, and check both settings in Chrome.