Twenty Twelve Problems with Media query

Hi,

I have been looking in forums for days now, but cannot find the answer to my problem.
I am using a child theme of Twenty Twelve. In the header I want my logo on the left and my adress in a block on the right.
On smaller screens I would like the adress block to not show up at all, but whatever I try with media queries – it doesn’t work. It’s like whatever I write in the @media doesn’t respond.

– Oh, and I am not good at all with php and css. So apologies in advance for any stupid question.

What I have done:
header php:
<h1 class=”site-title”>” title=”<?php echo esc_attr( get_bloginfo( ‘name’, ‘display’ ) ); ?>” rel=”home”><img src=”<?php echo bloginfo(‘stylesheet_directory’);?>/Images/Logo_300.png” alt=”<?php bloginfo( ‘name’); ?>” style=”width:300px;” />

</h1>
<h2 class=”site-description”><?php bloginfo( ‘description’ ); ?>
Christine Dietrich
Giblenstrasse 51
8049 Zürich
+41 77 486 6971
christine@entdeckungsreiseninsleben.com </h2>
</hgroup>

Style.css:
.site-header h2 {
border-bottom: 0.5px solid #A4A4;
text-align: right;
line-height:1.3em;
font-size:13px;
color: #a4a4a4;
position:absolute;
top:160px;
right:120px;
width:300px;
height:120px;
padding: 10px;
display: none;
}
@media screen and (min-width: 960px) {

.site-header h2 {
display: inline-block;
}
}

The problem is that the media query does not respond, i.e. the adress block does not show up in a bigger screen.

Thank you very much for your help. Much appreciated!!!!!