split scss into separate files

src/components/editor.scss

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2020-2021 The Pybricks Authors
+
+// Custom styling for the Editor control.
+
+@import '../variables.scss';
+
+.bp3-dark .ace_gutter {
+    // make ace editor match app backgound color
+    background-color: $pt-dark-app-background-color;
+}
+
+.ace_gutter {
+    // make ace editor match app backgound color
+    background-color: $pt-app-background-color;
+}
+
+.watermark::after {
+    content: "";
+    background: url("./images/beta.svg");
+    opacity: 1;
+    top: 0;
+    left: 0;
+    bottom: 0;
+    right: 0;
+    position: absolute;
+    pointer-events: none
+}