Extract variable for yellow color in icons

Signed-off-by: fnuesse <felix.nuesse@t-online.de>

apps/files/css/files.scss

@@ -704,7 +704,7 @@ table.dragshadow td.size {
 		background-image: none;
 	}
 	& .icon-starred {
-		@include icon-color('star-dark', 'actions', 'FC0', 1, true);
+		@include icon-color('star-dark', 'actions', $color-yellow, 1, true);
 	}
 }
 

core/css/icons.scss

@@ -282,13 +282,13 @@ img, object, video, button, textarea, input, select, div[contenteditable='true']
 	&:focus {
 		@include icon-color('star', 'actions', $color-black, 1, true);
 	}
-	@include icon-color('star-dark', 'actions', 'FC0', 1, true);
+	@include icon-color('star-dark', 'actions', $color-yellow, 1, true);
 }
 
 .icon-star {
 	&:hover,
 	&:focus {
-		@include icon-color('star-dark', 'actions', 'FC0', 1, true);
+		@include icon-color('star-dark', 'actions', $color-yellow, 1, true);
 	}
 }
 

core/css/variables.scss

@@ -53,6 +53,7 @@ $color-success: #46ba61;
 // used for svg
 $color-white: #fff;
 $color-black: #000;
+$color-yellow: #FC0;
 
 // rgb(118, 118, 118) / #767676
 // min. color contrast for normal text on white background according to WCAG AA