Fringe face generated with wrong color?

[dgutov]

Example: http://tmtheme-editor.herokuapp.com/#/theme/Made%20by%20phunky

I don't have a tm2theme-compatible editor at hand, but the above page shows gutter with a pretty light background. However, when I load the converted theme in Emacs, the fringe face is pretty dark (a6a6ac), noticeably darker than the mode-line and the background color of comments.

To be fair, I don't see a specific color for the gutter background in the theme's definition.