Accessibility - ajvondrak/vondark GitHub Wiki

The vondark color scheme is not explicitly designed for accessibility.

However, it may be worth noting that the foreground/background contrast ratios for the basic syntax groups tend to be at least 4.5:1 (WCAG 2.0 level AA). There are some exceptions, like for Statement (4.33, AA only for large text) and Error (2.4, a complete failure). Several are above the AAA 7:1 ratio.

Group	Foreground	Background	Ratio	WCAG Level
`Normal`	`#cccccc`	`#1a1a1a`	10.84	AAA
`Comment`	`#999999`	`#1a1a1a`	6.11	AAA 18pt
`Constant`	`#ffc400`	`#1a1a1a`	10.9	AAA
`String`	`#ffc400`	`#333333`	7.91	AAA
`Number`	`#ff8a50`	`#1a1a1a`	7.46	AAA
`Identifier`	`#6ec6ff`	`#1a1a1a`	9.27	AAA
`Statement`	`#2978ff`	`#1a1a1a`	4.33	AA 18pt
`PreProc`	`#9a67ea`	`#1a1a1a`	4.56	AAA 18pt
`Type`	`#80e27e`	`#1a1a1a`	10.86	AAA
`Special`	`#dc67ea`	`#1a1a1a`	5.94	AAA 18pt
`Underlined`	`#8eacbb`	`#1a1a1a`	7.27	AAA
`Error`	`#cccccc`	`#ff1744`	2.4	FAIL
`DiffAdd`	`#80e27e`	`#333333`	7.88	AAA
`DiffDelete`	`#ff1744`	`#333333`	3.28	AA 18pt
`DiffChange`	`#ffc400`	`#333333`	7.91	AAA
`DiffText`	`#ff8a50`	`#333333`	5.42	AAA 18pt
`Visual`	`#1a1a1a`	`#8eacbb`	7.27	AAA
`IncSearch`	`#1a1a1a`	`#ff8a50`	7.46	AAA
`Search`	`#1a1a1a`	`#ffc400`	10.9	AAA

Other combinations occur in the wild, such as MatchParen changing the background of some delimiter that may or may not be highlighted in a particular color. The relative contrast between separate syntax elements is also important (e.g., is PreProc sufficiently distinguishable from Type?). I have not checked these scenarios, so there may be several bad combinations. Even for the basic syntax above, colorblindness checks fail across the board.

The UI elements generally involve greys on top of greys, so the contrast will be much lower outside the bounds of basic syntax. This is done on purpose (e.g., I want CursorLine and LineNr to be less visible), but may obviously be unsuitable for certain visual needs.