Choose the Chart That Matches the Question

By default a chart takes its series colors from the deck's color scheme. Series 1 to 6 use accent1 to accent6 of the scheme in that order; series 7 to 12 use the same six accents mixed 40% toward white (series 7 is a tint of accent1). A pie, doughnut, treemap or funnel gives category i color i. Charts with more than twelve series repeat the list.

Put the series that carries the message first, because accent1 is the deck's primary, and keep a chart to six series or fewer so no tint is needed. Each color is then adjusted so it keeps 3:1 contrast against the chart panel and stays apart from its neighbours; on a dark panel colors are lightened, never merged.

To set a series color yourself, give the chart chart.colors: a list of up to 24 colors by position, where entry i replaces the palette color of series (or slice, for a pie) i and the rest of the palette is unchanged. An entry is any ColorRef: a hex color, a color-scheme slot or role such as accent3 (it follows the deck if its scheme changes), or a var: color variable. The contrast adjustment still applies to authored colors, and the opf/chart-colors-adjusted warning says when an entry was unresolvable or had to be moved.

"chart": {
  "type": "column",
  "data": { "columns": ["Quarter", "Revenue", "Costs"], "rows": [["Q1", 12, 8], ["Q2", 18, 11]] },
  "colors": ["accent3", "#7B241C"]
}

highlight wins over both: the series and categories it names take the deck's primary color and every other mark takes a muted neutral, whatever chart.colors says.

Core 0.21.0 behavior.