[BUG] rgba is limited from :style in yuck

[ArtemSmaznov]

Checklist before submitting an issue

• I have searched through the existing closed and open issues for eww and made sure this is not a duplicate
• I have specifically verified that this bug is not a common user error
• I am providing as much relevant information as I am able to in this bug report (Minimal config to reproduce the issue for example, if applicable)

Description of the bug

Is there a reason why rgba() behaves differently between cscc and yuck?

This works fine:

.music-player {
    background: rgba(#FF0000, 0.4);
}

This for some reason doesn't:

(box :class "music-player"
     :style "background: rgba(#FF0000, 0.4);"

It works fine without the opacity though:

(box :class "music-player"
     :style "background: #FF0000;"

To clarify what I am trying to do.
I have a var music-player-album-color in yuck and I want to make the music player widget have a dynamic color AND be semi-transparent. I can get to having either one of those but not both.

I have even tried setting a new scss variable from yuck but it seems anything set there operates on a different scope than what I write in scss so couldn't get this working as a workaround.

Is there a bug in how rgba() in handled from yuck or is this a limitation that is easy to overcome?

Reproducing the issue

Add the following to any widget

     :style "background: rgba(#FF0000, 0.4);"

Expected behaviour

the widget should get colored accordingly (40% transparent red)

Additional context

No response