I am trying to resize an image. Bootstrap is enabled.

Here's my CSS:
/*Custom picture fix*/
@media(max-width:600px){
.picturerow>img {
width: 10px;
height: auto;
}
}
Here's my HTML:
<div class="picturerow">
<ul>
<li><img src="{{ asset('assets/img/icons-medium/facebook-medium.png') }}" alt="facebook-icon"> </li>
<li><img src="{{ asset('assets/img/icons-medium/linkedin-medium.png') }}" alt="linkedin-icon"> </li>
<li><img src="{{ asset('assets/img/icons-medium/twitter-medium.png') }}" alt="twitter-icon"> </li>
<li><img class="img-responsive" src="{{ asset('assets/img/icons-medium/xing-medium.png') }}" alt="xing-icon"> </li>
<li><img class="img-responsive" src="{{ asset('assets/img/icons-medium/google-medium.png') }}" alt="google-icon"> </li>
</ul>
</div>
What am I doing wrong?
The pictures should all be displayed inline, and for screen sizes of md and smaller (no less, sass etc) they should be displayed in the middle. On the very small screens, the pictures should all be 15px width and keep the ratio.