diff --git a/src/renderer/app.css b/src/renderer/app.css
new file mode 100644
index 0000000..48cd141
--- /dev/null
+++ b/src/renderer/app.css
@@ -0,0 +1,12 @@
+/* Adapted from scratch-gui/src/playground/index.css */
+html,
+body,
+.app {
+    width: 100%;
+    height: 100%;
+    margin: 0;
+
+    /* Setting min height/width makes the UI scroll below those sizes */
+    min-width: 1024px;
+    min-height: 640px; /* Min height to fit sprite/backdrop button */
+}
diff --git a/src/renderer/index.js b/src/renderer/index.js
index ec2d38e..427d3b9 100644
--- a/src/renderer/index.js
+++ b/src/renderer/index.js
@@ -1,12 +1,13 @@
 import React from 'react';
 import ReactDOM from 'react-dom';
-
 import GUI, {AppStateHOC} from 'scratch-gui';
-import {defaultProjectId} from 'scratch-gui/src/reducers/project-state';
-import styles from 'scratch-gui/src/playground/index.css';
 
 import ElectronStorageHelper from '../common/ElectronStorageHelper';
 
+import styles from './app.css';
+
+const defaultProjectId = 0;
+
 // Register "base" page view
 // analytics.pageview('/');