Bug #1579628: Fixed invisibible password label in theme "Modern"

When a wrong password was entered on the login scrren, the password label
could not be read because it was white on white in the "Modern" theme.

Is a generic issue with Modern theme forms

behatnotneeded

Change-Id: I37c29633b247b60c08760f7c90dc8937f629dd81

htdocs/theme/modern/sass/_custom.scss

@@ -46,3 +46,13 @@ body {
     border-color: lighten($gray-light, 50%) !important;
   }
 }
+
+// Makes the text darker and field show red outline when a form error is shown
+.has-error {
+  label {
+    color: #545B5D;
+  }
+  .form-control {
+    border-color: #CF2C33;
+  }
+}
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