Built-in iced themes and custom palette support.

Each built-in theme is an atom that maps to the corresponding iced::Theme variant on the Rust side. Custom themes are plain maps that the renderer parses into an iced::Theme::custom() palette.

Extended palette shade overrides

Custom themes automatically generate shade variants (strong, weak, etc.) from the six core palette colors using iced's Oklch-based algorithm. If you need precise control over specific shades, you can override them with flat keys in the theme map. Shade overrides only apply to custom themes -- built-in themes are not affected.

Each shade key targets a specific Pair (background color + text color) in the extended palette. Append _text to any shade key to override the text color for that shade.

Color families (base, weak, strong)

primary, success, warning, danger are core palette seeds (set via custom/2). secondary is auto-derived from background and text by iced's palette generator.

All five families support shade overrides: {family}_base, {family}_weak, {family}_strong, plus _text variants.

Background family (8 levels)

background_base, background_weakest, background_weaker, background_weak, background_neutral, background_strong, background_stronger, background_strongest, plus _text variants.

Example

# Custom theme with shade overrides
theme = %{
  name: "my-theme",
  background: "#1a1a2e",
  text: "#e0e0e0",
  primary: "#0f3460",
  primary_strong: "#1a5276",
  primary_strong_text: "#ffffff",
  background_weakest: "#0d0d1a"
}

Any shade key you omit keeps the auto-generated value.

Widget chrome colour tokens

Custom themes can also carry theme-level colour tokens for cursor and scrollbar styling:

• cursor_color
• scrollbar_color
• scroller_color

These values are cast as colours and sent in the custom theme map. The renderer uses scrollbar tokens as scrollable defaults. The cursor token applies to focused text entry widgets through iced's focused text style, and explicit widget text styling still wins.