Mail, Phone and twitter icons don't fit when I type in Nicks Code.

I am working on the how to build a web site course with Nick Petit and the twitter phone and mail icons wont fit after i put nicks ccs code in to my main.css file. My first thought was that I made a mistake and entered a value in wrong. I checked the code over multiple times. I have even completely redone the course from the ''building the contact page'' video. Still, The icons appear jumbled after entering the links to the icons in the file tree and styling with the css from the video. Up to this point I have gotten everything to work exactly the way it does in the video.

/******************* page contact *******************/

.contact-info { list-style: none; padding: 0; margin: 0; font-size: 0.9em; }

.contact-info a { display: block; min-height: 20px; background-repeat: no-repeat; background-size; 20px 20px; padding: 0 0 0 30px; margin: 0 0 10px; }

.contact-info li.phone a { background-image: url('../img/phone.png'); }

.contact-info li.mail a { background-image: url('../img/mail.png'); }

.contact-info li.twitter a { background-image: url('../img/twitter.png'); }