[gnome-music/cherry-pick-4011eb91] data: Fix dark mode album tiles

[Marinus Schraal <mschraal src gnome org>]

commit 5b4352176942705e57131135d8df8bdafbb4810d
Author: Marinus Schraal <mschraal gnome org>
Date:   Tue Sep 18 09:29:33 2018 +0000

    data: Fix dark mode album tiles
    
    By default the Adwaita dark .tile has no transparent background, but in the
    Music case it looks better that way.
    
    
    (cherry picked from commit 4011eb91c387f09c2c914ffbb979fc6094f05afe)

 data/application.css | 5 +++++
 1 file changed, 5 insertions(+)
---
diff --git a/data/application.css b/data/application.css
index 1b9e0176..528fe975 100644
--- a/data/application.css
+++ b/data/application.css
@@ -17,6 +17,11 @@ flowbox, treeview, widget {
     font-size: smaller;
 }
 
+/* By default in Adwaita dark this is not transparent */
+.tile {
+    background-color: transparent;
+}
+
 /* AlbumWidget */
 .title-artist {
     font-size: larger;