.skyscrapers{width:1500px;margin:auto;position:sticky;top:0}
.skyscraper{display:none;width:120px;height:600px;margin-top:1em}
.ad-banner{margin:1em 0}
.ad-banner-top{display:none;padding:0.5em;}

@media only screen and (min-width: 750px) 
{
	.ad-banner-top{display:block}
}

@media only screen and (min-width: 1250px) 
{
    .skyscrapers{width:1100px}
    .skyscraper{width:120px;display:inline-block}
}
@media only screen and (min-width: 1350px) 
{
    .skyscrapers{width:1200px}
    .skyscraper{width:160px}
}
@media only screen and (min-width: 1650px) 
{
    .skyscrapers{width:1500px}
    .skyscraper{width:300px}
}