There is/was no such thing as a Hotmail interface.
What you saw was the standard look for ALL Microsoft email domains (hotmail.com, msn.com, outlook.com)
They implemented a new look to the webmail user interface. You still get your hotmail email.
More information here http://www.theverge.com/2015/5/21/8634979/microsoft-outlook-email-service-new-features-user-interface
If you don't like the new look, you do have an alternative. Use an email client such as Thunderbird. Configure it to work with your Hotmail account.
Install, configure, click the icon on the desktop, it opens, downloads mail from the server to your computer.
Edited by Queen-Evie, 04 June 2016 - 07:01 PM.