Themes
A theme is a named color palette that bundles the map background, the default land fill, border strokes, text colors, and the choropleth ramp (sequential, diverging, and categorical). Picking a theme sets the entire visual identity of the map with a single URL parameter.
There are six themes: three with light backgrounds and three with dark backgrounds.
Examples
All examples use the same data so the palettes are directly comparable.
light — white background, green sequential ramp
https://api.maproll.io/map.svg?scope=world&data=US:5,CN:4,IN:3,BR:2,RU:1&theme=light
light-blue — off-white background, blue sequential ramp
https://api.maproll.io/map.svg?scope=world&data=US:5,CN:4,IN:3,BR:2,RU:1&theme=light-blue
light-mono — near-white background, greyscale ramp
https://api.maproll.io/map.svg?scope=world&data=US:5,CN:4,IN:3,BR:2,RU:1&theme=light-mono
dark — navy background, amber sequential ramp
https://api.maproll.io/map.svg?scope=world&data=US:5,CN:4,IN:3,BR:2,RU:1&theme=dark
dark-blue — deep-blue background, blue sequential ramp
https://api.maproll.io/map.svg?scope=world&data=US:5,CN:4,IN:3,BR:2,RU:1&theme=dark-blue
dark-mono — near-black background, greyscale ramp
https://api.maproll.io/map.svg?scope=world&data=US:5,CN:4,IN:3,BR:2,RU:1&theme=dark-mono
Parameters
| Param | Type | Default | Allowed | Notes |
|---|---|---|---|---|
theme | string | dark | light, light-blue, light-mono, dark, dark-blue, dark-mono | Case-sensitive. Returns 400 if unrecognised. |
Picking a theme
light — best for print, editorial contexts, and embedding on white-background pages. Sequential ramp is green; diverging extremes are red/blue.
light-blue — same white-family background as light but with a blue sequential ramp. Works well for data that reads as "volume" or "flow" (traffic, imports, connectivity).
light-mono — greyscale throughout. Useful for publications that print in black-and-white, or for accessibility contexts where color cannot be the sole differentiator.
dark — navy background with an amber sequential ramp. The strongest visual contrast of the six themes; stands out in dark-mode dashboards and slide decks.
dark-blue — consistent blue across background, land, and ramp. Works well when the map is a supporting visual on a dark-branded page and you want tonal coherence.
dark-mono — near-black background with a grey ramp. The most minimal option; lets annotations, markers, and routes carry the visual weight.
Notes
- Every sequential and diverging ramp stop is tuned to have a minimum contrast ratio against the theme's land color, so the lowest-value region is always visually distinct from a no-data region.
- The
highlightcolor (used in regions-only mode, when nodata=values are provided) is theme-specific:#2563ebforlight,#60a5fafordark, and so on. - Passing an unknown theme name returns
400with{"error":"invalid_theme", ...}.
Related
- Color scales — sequential, diverging, and categorical ramps
- Color overrides — per-region hex fills that bypass the ramp
- GET /map — full query-parameter reference