Newsletter subscription form is the detail that can easily get you one step closer to the perfection. But it’s probably the most simple web form with just an input field and a submit button. "What more can you do with it?" you may ask. The first impression can be deceptive: there are quite a few things you can do with it, such as floating label, unusual visual approach, etc. But there’s one thing we’ll surely do now: hide the submit button by default and only show it if user enters the correct email address.