Only run PurgeCSS in production builds

vite.config.ts

@@ -4,7 +4,10 @@ import { svelte } from "@sveltejs/vite-plugin-svelte";
 import purgecss from "@fullhuman/postcss-purgecss";
 
 // https://vitejs.dev/config/
-export default defineConfig({
+export default defineConfig(({ command, mode, ssrBuild }) => {
+  // Only run PurgeCSS in production builds
+  if (command === "build") {
+    return {
       plugins: [svelte()],
       css: {
         postcss: {
@@ -15,4 +18,10 @@ export default defineConfig({
           ],
         },
       },
+    };
+  } else {
+    return {
+      plugins: [svelte()],
+    };
+  }
 });