new text editor block that contains core blocks as inner blocks and prevents them from being used at top level

resources/css/editor.scss

@@ -0,0 +1,53 @@
+@use "./app";
+
+.editor-styles-wrapper {
+  padding: 1em;
+  background: transparent;
+}
+
+.editor-visual-editor {
+  .wp-block {
+    max-width: none;
+  }
+
+  .block-list-appender {
+    width: 350px;
+    max-width: 90%;
+    margin: 1em auto;
+    background: white;
+  }
+
+  &__post-title-wrapper {
+    padding: 1rem;
+    margin: 0 0 3rem !important;
+    background: white;
+    box-shadow: 0 0.5rem 1rem rgba(black, 0.15);
+  }
+
+  .wp-block-post-title {
+    position: relative;
+    padding: 0.5rem;
+    border: 1px solid rgba(black, 0.3);
+    margin: 0;
+
+    &::before {
+      content: 'Page Title';
+      position: absolute;
+      top: -0.5rem;
+      left: 0.5rem;
+      color: rgba(black, 0.3);
+      font-size: 0.8rem;
+      display: block;
+      padding: 0 0.5rem;
+      margin: 0;
+      background: white;
+      line-height: 1;
+      font-weight: 400;
+    }
+  }
+
+  .wp-block-post-content {
+    // background: white;
+    // box-shadow: 0 0.5rem 1rem rgba(black, 0.15);
+  }
+}