diff --git a/.nvmrc b/.nvmrc
index 54954dc..d9b64a1 100644
--- a/.nvmrc
+++ b/.nvmrc
@@ -1 +1 @@
-20.0.0
\ No newline at end of file
+14.18.0
\ No newline at end of file
diff --git a/magicbook-html.json b/magicbook-html.json
index 4a2709a..0ea5b92 100644
--- a/magicbook-html.json
+++ b/magicbook-html.json
@@ -2,7 +2,7 @@
   "title": "Code of Music",
   "addPlugins": [
     "magicbook-codesplit",
-    "src/plugins/magicbook-webpack",
+    "magicbook-webpack",
     "src/plugins/p5",
     "src/plugins/inlineButton",
     "src/plugins/interactiveSketch"
diff --git a/magicbook-pdf.json b/magicbook-pdf.json
index f828a9c..5ad2f69 100644
--- a/magicbook-pdf.json
+++ b/magicbook-pdf.json
@@ -2,7 +2,7 @@
   "title": "Code of Music",
   "addPlugins": [
     "magicbook-codesplit",
-    "src/plugins/magicbook-webpack",
+    "magicbook-webpack",
     "src/plugins/p5",
     "src/plugins/inlineButton",
     "src/plugins/interactiveSketch"
diff --git a/package.json b/package.json
index 8d6f01f..8c82efa 100644
--- a/package.json
+++ b/package.json
@@ -28,8 +28,9 @@
     "copy-webpack-plugin": "6",
     "highlight.js": "^11.2.0",
     "liquidjs": "^9.25.1",
-    "magicbook": "^0.1.33",
+    "magicbook": "^0.1.19",
     "magicbook-codesplit": "^0.1.6",
+    "magicbook-webpack": "0.0.4",
     "monaco-editor": "0.33.0",
     "p5": "^1.4.0",
     "path": "^0.12.7",
@@ -41,11 +42,10 @@
     "source-map-loader": "^3.0.0",
     "tinyliquid": "^0.2.34",
     "tone": "^14.7.77",
-    "webpack": "^5.0.0"
+    "webpack": "^4.42.1"
   },
   "devDependencies": {
     "firebase-tools": "^9.16.0",
     "live-server": "^1.2.1"
-  },
-  "packageManager": "yarn@4.1.1"
+  }
 }
diff --git a/src/stylesheets/html.scss b/src/stylesheets/html.scss
index c6c04bf..7077dec 100644
--- a/src/stylesheets/html.scss
+++ b/src/stylesheets/html.scss
@@ -349,7 +349,7 @@ section[data-type='sect1'] {
   top: 0;
   left: 0;
   padding: $menu-padding;
-  padding-top: calc($header-height / 2);
+  padding-top: $header-height / 2;
   display: block;
   @media (max-width: $bp-medium) {
     box-shadow: 0 0 100px rgba(0, 0, 0, 0.2);
diff --git a/webpack.config.js b/webpack.config.js
index 50fbf33..cd56a68 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -6,7 +6,7 @@ const config = {
   entry: './src/javascripts/app.js',
   output: {
     path: 'assets',
-    filename: 'app-[fullhash].js',
+    filename: 'app-[hash].js',
   },
   module: {
     rules: [