Form: add pseudo native form validation

app/assets/stylesheets/new_design/forms.scss

@@ -58,6 +58,17 @@
     max-width: 180px;
   }
 
+  input:invalid,
+  textarea:invalid {
+    box-shadow: none;
+  }
+
+  input.touched:invalid,
+  textarea.touched:invalid {
+    border-color: $dark-red;
+    box-shadow: 0px 0px 5px $dark-red;
+  }
+
   select,
   .select2-selection {
     // hack found here: https://stackoverflow.com/questions/1895476/how-to-style-a-select-dropdown-with-css-only-without-javascript