A paired fixture for colored side borders and rounded accent borders. The left column should produce border findings; the right column should stay clean.
Classic side tab: border-left is thick, colored, and paired with rounded corners.
The right-side version is the same visual trope mirrored.
The stripe runs down the square edge and the far corners are rounded: the tab shape.
The utility-class form writes border-top-right-radius and border-bottom-right-radius instead of the shorthand; the card is just as round.
A radius the engine cannot resolve is unknown, not square, so the stripe on it is still reported.
A heavy top accent on a rounded card is the horizontal variant of the same pattern.
The bottom accent is also a decorative stripe on a card surface.
Dark surfaces can hide the cliche, but the thick colored side stripe remains.
A quiet all-around border frames the card instead of creating a side tab.
A gray structural rule can be a legitimate divider when it is not chromatic emphasis.
A 1px colored rule is below the decorative side-tab threshold.
A live status region carries a colored side bar as a severity accent, not a decorative side tab.
A side rule on square corners is the old callout convention: a quote, a note, a table row marker.
The corners away from the stripe are square, so the card does not read as a rounded tab.
A chromatic top band on a square box is a rule across a section, not a card's accent (r6-t2).
A chromatic bottom band on a square box is the same rule, and stays silent too.
An active-state underline inside a tablist is an affordance, not a stripe.
A band well past stripe thickness is a compositional block, not an accent stripe.
The dark surface has a full neutral outline, not a chromatic side stripe.