Enable building css so that you can run blacklight without sass

app/assets/builds/blacklight.css

@@ -0,0 +1,22 @@
+/* Error: Undefined mixin.
+ *   ,
+ * 6 |       @include visually-hidden;
+ *   |       ^^^^^^^^^^^^^^^^^^^^^^^^
+ *   '
+ *   app/assets/stylesheets/blacklight/_mixins.scss 6:7           @content
+ *   bootstrap/scss/mixins/_breakpoints.scss 81:5                 media-breakpoint-down()
+ *   app/assets/stylesheets/blacklight/_mixins.scss 5:5           @import
+ *   app/assets/stylesheets/blacklight/_blacklight_base.scss 9:9  @import
+ *   app/assets/stylesheets/blacklight/blacklight.scss 5:9        @import
+ *   app/assets/stylesheets/blacklight/build.scss 4:9             root stylesheet */
+
+body::before {
+  font-family: "Source Code Pro", "SF Mono", Monaco, Inconsolata, "Fira Mono",
+      "Droid Sans Mono", monospace, monospace;
+  white-space: pre;
+  display: block;
+  padding: 1em;
+  margin-bottom: 1em;
+  border-bottom: 2px solid black;
+  content: "Error: Undefined mixin.\a   \2577 \a 6 \2502        @include visually-hidden;\a   \2502        ^^^^^^^^^^^^^^^^^^^^^^^^\a   \2575 \a   app/assets/stylesheets/blacklight/_mixins.scss 6:7           @content\a   bootstrap/scss/mixins/_breakpoints.scss 81:5                 media-breakpoint-down()\a   app/assets/stylesheets/blacklight/_mixins.scss 5:5           @import\a   app/assets/stylesheets/blacklight/_blacklight_base.scss 9:9  @import\a   app/assets/stylesheets/blacklight/blacklight.scss 5:9        @import\a   app/assets/stylesheets/blacklight/build.scss 4:9             root stylesheet";
+}

app/assets/stylesheets/blacklight/build.scss

@@ -0,0 +1,4 @@
+@import "bootstrap/scss/functions";
+@import "bootstrap/scss/mixins/breakpoints";
+@import "bootstrap/scss/variables";
+@import "blacklight";

package.json

@@ -6,6 +6,7 @@
   "type": "module",
   "module": "app/assets/javascripts/blacklight/blacklight.esm.js",
   "scripts": {
+    "build": "sass ./app/assets/stylesheets/blacklight/build.scss:./app/assets/builds/blacklight.css --no-source-map --load-path=node_modules",
     "prepare": "rollup --config rollup.config.js --sourcemap && ESM=true rollup --config rollup.config.js --sourcemap"
   },
   "repository": {
@@ -24,7 +25,9 @@
   "homepage": "https://github.com/projectblacklight/blacklight#readme",
   "devDependencies": {
     "rollup": "^4.24.0",
-    "rollup-plugin-includepaths": "^0.2.4"
+    "rollup-plugin-includepaths": "^0.2.4",
+    "sass": "^1.80.3",
+    "bootstrap": "^5.3.3"
   },
   "browserslist": [
     "defaults",