URL Field Missing Outline in Send Data Handler

[Nicholas-Westby]

When you create a send data handler, this is what you're supposed to see (screenshot from Umbraco 7.4.3):

Notice that the URL field has an outline that fades out to the right.

In Umbraco 7.10.4, that outline is not present:

This makes it confusing when entering the URL, because it seems as if you're supposed to enter the URL into the alias field (because it seems like the alias field is actually the "Handler Alias URL" field).

Need to modify the styles so this works in newer versions of Umbraco.