Transparent colors show as @app-background-color

[Arcanemagus]

Prerequisites

Note: By definition this is impossible to test in safe mode as none of the bundled themes fit this description.

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Description

When a color is set to transparent, it shows in the styleguide as the same color as @app-background-color. Should this be changed to show these colors as explicitly transparent?

Steps to Reproduce

1. Install a theme that uses transparent as a color (eg. atom-material-ui and @base-background-color here)
2. Activate the theme and open the Styleguide
3. Look at the color set as transparent in the theme and note how it is the same as @app-background-color.

Expected behavior:
Some indication that the color is transparent. I'm not a theme developer though, so maybe this is just as expected and should be left as is.

Actual behavior:
No indication that this color actually has nothing set.

Reproduces how often:
100% of the time.

Versions

Atom : 1.17.0-beta3
Electron: 1.3.14
Chrome : 52.0.2743.82
Node : 6.5.0