Design & Frontend
There is almost no taste in this category — everything is measurable. Contrast is a ratio, icons are pixels or vectors, colour is three channel values. That makes the criteria writable: body text at 4.5:1, 16px icons drawn separately, never JPEG for transparency.
The difficulty is that these numbers are not intuitive. Yellow and blue at the same lightness look nothing alike; a 512px icon may be unrecognisable at 16px. The guides explain why the intuition fails rather than listing rules.
- Favicon Sizes: The Complete ChecklistA 16-pixel icon and a 512-pixel icon are not the same image scaled. The file set that still works in 2026, the maskable safe zone, why browsers ignore your new icon, and what breaks when you ship one big PNG.
- WCAG Contrast: How to Calculate and Fix ItContrast is a ratio between two relative luminances, which is why "darken the text a bit" sometimes lowers it. The formulas, the AA and AAA thresholds, and the three fixes that work without wrecking the palette.