Proposal: add a 'positive' colour

[kr8n3r]

Copied over from GOV.UK Frontend toolkit

There are cases where it's useful to have a colour with a semantic meaning of 'positive'.

We already have error_colour which is a good red for 'negative' - but we don't have a counterpart.

We could use an existing colour, or make a new colour. Either way, a semantic SASS name would be good.

The closest colour would be button_colour. An alternate would be #008800 which is the green used by petitions. It's warmer, which feels more positive to me.

[fofr]

In https://whitehall-prototype.herokuapp.com/patterns/flash-notices we are using the button colour.

[edwardhorsford]

I might also suggest we possibly make a 'negative' colour that references error-colour. Semantic names FTW.

Use cases

We used positive / negative on the first version of the Performance Platform.

Certain other services which include tables / graphs may also benefit. I'm thinking things like flood warnings / travel advice.

[dashouse]

Be aware, Mark Hurell has some broader colour changes coming up. I would not suggest adding any other colours to the palette.

[kr8n3r]

closing, will await colour changes