fix: use defaults in open edx theme vars too

Author: Adam Butterworth

package.json

@@ -3,7 +3,7 @@
   "description": "The Bootstrap theme for Open edX",
   "license": "Apache-2.0",
   "repository": "[email protected]:edx/edx-bootstrap.git",
-  "version": "2.0.0",
+  "version": "1.0.4",
   "homepage": "http://edx.github.io/edx-bootstrap",
   "scripts": {
     "start": "react-scripts start",

scss/open-edx/custom/_edx-custom-card.scss

@@ -1,11 +1,11 @@
-$charcoal-grey: #393f43;
-$dark-slate-blue: #17285d;
-$ice-blue: #f5f8ff;
-$sapphire: #23419f;
-$silver: #d6dbe0;
-$slate-grey: #636c72;
-$light-border: 1px solid $silver;
-$edx-shadow-color: rgba(0, 0, 0, 0.3);
+$charcoal-grey: #393f43 !default;
+$dark-slate-blue: #17285d !default;
+$ice-blue: #f5f8ff !default;
+$sapphire: #23419f !default;
+$silver: #d6dbe0 !default;
+$slate-grey: #636c72 !default;
+$light-border: 1px solid $silver !default;
+$edx-shadow-color: rgba(0, 0, 0, 0.3) !default;
 
 @mixin edx-shadow {
   box-shadow: 0 2px 2px 0 $edx-shadow-color;