check to
HTML
<ul class="social-media-nav-center">
<li>
<a href="https://twitter.com/" target="_blank"><img id="twitter" class="small" src="https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcRgdlWvqZIB0r6qkjFS_t9uMKD9gQIVMV3fE-Vw9BMoRfNEmJG2" />
</a>
</li>
</ul>
Jquqey
$(document).ready(function(){
$(window).scroll(function(){
if($(window).scrollTop() > $(window).height()) {
$("#twitter").attr("src", "http://www.planwallpaper.com/static/images/744081-background-wallpaper.jpg");
}
})
})
CSS
.social-media-nav-center{height:1000px;}
2
solved Changing img src in jQuery