Moved $colors list into variables

Also renamed it because it would cause a collission with Bootstraps $colors surely at some point.

app/assets/stylesheets/_variables.scss

@@ -1,4 +1,4 @@
-// Colors
+// Color overrides for Bootstrap
 $primary: #5e35b1;
 
 // Cards
@@ -10,6 +10,15 @@ $list-group-border-width: 0;
 // nProgress
 $nprogress-color: lighten($navbar-inverse-bg, 25%);
 
+// Color names for theme generation
+$colorNames: (
+  "primary", 
+  "danger",
+  "warning",
+  "info",
+  "success"
+);
+
 :root {
   --background: #f0edf4;
   --card-bg: #ffffff;

app/assets/stylesheets/overrides/_buttons.scss

@@ -1,12 +1,4 @@
-$colors: (
-  "primary", 
-  "danger",
-  "warning",
-  "info",
-  "success"
-);
-
-@each $color in $colors {
+@each $color in $colorNames {
   .btn-#{$color} {
     background-color: var(--#{$color});
     border-color: var(--#{$color});

app/assets/stylesheets/overrides/_colors.scss

@@ -1,12 +1,4 @@
-$colors: (
-  "primary", 
-  "danger",
-  "warning",
-  "info",
-  "success"
-);
-
-@each $color in $colors {
+@each $color in $colorNames {
   .bg-#{$color} {
     background-color: var(--#{$color}) !important;
   }