Set image width a class.

Hello,

I’m a CSS n00b, I REALLY need your help please, I’m going crazy:

I’m unable to set the width of an image using a class. That’s what I do:

In my style.css I set (for example) the class:

.pippo {width: 20px;};

In my html:

<img class=”pippo”; src=”http://www.webfoodculture.com/wp-content/uploads/2015/06/antip_001_crocvic01.jpg&#8221;; />

… result, just nothing! The image keeps the original size.

Many thanks in advance for your help!

A.