Change value data attribute with mediaquery
<p>I create my website and i've got a problem with an attribute of a div.
I try to change the value when the screen is small.</p>

<p>My css mediaquery:</p>

<pre><code>@media screen and (min-width: 1000px) and (max-width: 2000px) {
#my-content { display: block; }
#my-slider {width: 670px;}

}

@media screen and (min-width: 0px) and (max-width: 1000px) {
#my-content { display: none; }   /* hide it elsewhere */
#my-text {font-size: 26px;}
#my-slider {content: attr(data-x : 700) ;}
}
</code></pre>

<p>My html :</p>

<pre><code>&lt;div id="my-slider" class="caption sfb" data-x="500" data-y="0" data-speed="900" data-start="900" data-easing="easeOutSine"&gt;&lt;img src="code1.jpg" width="670px" height="500px"  alt="" /&gt;&lt;/div&gt;
</code></pre>

<p>I want to change the data-x but don't work with all possibilities i've found...Can you help me? Thanks.</p>