reset margin property of form controls

src/App.scss

@@ -131,6 +131,7 @@ input, textarea, .select {
   font-family: sans-serif;
   font-family: var(--inputFont, sans-serif);
   font-size: 14px;
+  margin: 0;
   padding: 8px .5em;
   box-sizing: border-box;
   display: inline-block;