set textarea with border None, resize none, width 100% styles

backstage/static/styles/main.css

@@ -60,4 +60,10 @@
 
 a.bg-dark {
   background-color: #132644 !important;
-}
+}
+
+textarea {
+  border: None;
+  resize: None;
+  width: 100%;
+}