Why it matters
Dozens of near-identical grays and tints mean colors were picked ad hoc instead of from a scale; the UI looks noisy and dark mode becomes impossible to maintain.
How to fix it
Use a 12-step neutral scale plus one accent scale exposed as semantic tokens (--bg, --surface, --fg, --fg-muted, --line, --brand…).
More design rules
void design reports 19 rules in this category. Measured design heuristics from computed styles: font families, type scale, line length, palette and accent sprawl, spacing grid, radius sprawl, dark mode and the tells of generated UI.
body-text-smallBody text is smaller than 15px on mobilebody-line-height-tightBody line-height is too tightheading-trackingLarge headings use default letter-spacingheading-no-balanceHeadings do not use text-wrap: balancemultiple-accentsMore than one accent huegradient-textGradient-filled heading textpurple-gradientPurple/indigo gradient backgroundemoji-iconsEmoji used as icons