Responsive design landscape issue

Im working with responsive design landscape for a website, but everytime the website get refreshed or when you click on the menu, the css for it doesnt apply. Only on the first page when you first enter it. Im using a theme named pinboard. The problem is with design in the phone, not a big screen.

The website: https://www.retorikgruppen.se

@media screen and (max-width: 1120px) {
.threefourthcol { width: 100%;  }
.threefourthcol .threecol { width: 100%; }
 .fourcol,  .onecol .fourcol {  width: 100%; }
#wrapper {  max-width:100%; }
 #slider .entry-container { top:28%;    }   

.threefourthcol .threecol .entry,   .onecol .fourcol .entry, .fourcol .widget
{       margin: 5%;     } 

img.attachment-gallery-thumb {  max-width:82px;     }
.twocol img.attachment-gallery-thumb {      max-width:74px;     }
.single img.attachment-gallery-thumb {      max-width:100%; }
format-audio object {   min-height:24px;    }
 .single .format-audio object { height:24px;    }
 .social-bookmarks iframe {         min-height:0;   }
 #sidebar-header {      width:468px;        height:60px;        margin-top:20px;    }
}