as part of the upstream vendor style initiative (see gnome discourse link and Exchange hardcoded colours with exported colours in gtk apps)
Yaru has borrowed its palette from Unity8 at the beginning, but then we diverged for many reasons. The goal is to expose this palette for App developers to pick them if needed, instead that hardcoding them into the app, looking then out of place when changing theme.
I’d like to merge the work done so far, officially introducing some colors and, if possible, come closer to the work already done by Ubuntu design team.
Here the current ubuntu color definitions in Yaru: https://github.com/ubuntu/yaru/blob/master/gtk/src/default/gtk-3.20/_ubuntu-colors.scss
while here the Suru icon palette https://snwh.org/suru/guidelines
Below some reference links:
Ubuntu touch color palette
In order of appearance:
Porcelain. Recommended for foregrounds.
Silk. Recommended for neutral action buttons and secondary text.
Ash. Recommended for subtitles and other tertiary content.
Graphite. Recommended for coloring dark themes’ background.
Slate. Recommended for text and action icons.
Inkstone. Recommended for foreground colors in dark themes.
Jet. Recommended for content coloring.
Orange. Recommended for branded elements, display progress and intensity, textual links on light backgrounds.
Purple. Recommended for proper nouns in list items.
Red. Recommended for negative and irreversible action buttons, errors and alerts.
Green. Recommended for positive action buttons.
Blue. Recommended for text selection and text cursor.