diff --git a/playground.nix b/playground.nix
index b0ac5ca..8be94d8 100644
--- a/playground.nix
+++ b/playground.nix
@@ -11,7 +11,7 @@ pkgs.buildNpmPackage {
 
   src = ./playground;
 
-  npmDepsHash = "sha256-gSP3f9loTPkeYK3l0Q1d28QXhujErE19k92flsh7EzA=";
+  npmDepsHash = "sha256-+Nyy05KFyLF2T9LtjgJ+KmrnICTXi1ylP4GFNbe8C64=";
 
   nativeBuildInputs = [
     pkgs.wasm-bindgen-cli
diff --git a/playground/package-lock.json b/playground/package-lock.json
index 8ee5cb9..19373ae 100644
--- a/playground/package-lock.json
+++ b/playground/package-lock.json
@@ -897,9 +897,9 @@
       "license": "MIT"
     },
     "node_modules/nanoid": {
-      "version": "3.3.11",
-      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.11.tgz",
-      "integrity": "sha512-N8SpfPUnUp1bK+PMYW8qSWdl9U+wwNWI4QKxOYDy9JAro3WMX7p2OeVRF9v+347pnakNevPmiHhNmZ2HbFA76w==",
+      "version": "3.3.19",
+      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.19.tgz",
+      "integrity": "sha512-Y2tUNy4ouw6tq5oDSKeQYGOyhkUBhNOcGV/02KC+6kd9eDGqdZd++mjMiIDilrBYvjEnCYvVtsuHCuP+okSfug==",
       "dev": true,
       "funding": [
         {
diff --git a/playground/tests/dependencies/nanoid.test.mjs b/playground/tests/dependencies/nanoid.test.mjs
new file mode 100644
index 0000000..fa8715e
--- /dev/null
+++ b/playground/tests/dependencies/nanoid.test.mjs
@@ -0,0 +1,20 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { nanoid } from 'nanoid';
+import postcss from 'postcss';
+
+test('PostCSS Input IDs remain nonempty and distinct for anonymous stylesheets', () => {
+  const first = postcss.parse('.editor { color: red }').source.input;
+  const second = postcss.parse('.editor { color: blue }').source.input;
+  assert.match(first.id, /^<input css .+>$/);
+  assert.notEqual(first.id, second.id);
+  assert.equal(first.css, '.editor { color: red }');
+});
+
+test('generated stylesheet identifiers preserve the requested size and URL-safe alphabet', () => {
+  for (const size of [0, 6, 21, 64]) {
+    const id = nanoid(size);
+    assert.equal(id.length, size);
+    assert.match(id, /^[A-Za-z0-9_-]*$/);
+  }
+});