We set the overflow-x values to hidden on both the body and scrollable elements, but mobile Safari ignores these values. On the desktop, the overflow values work fine.
Relevant code:
body { overflow-x:hidden; width:320px; height:100%; min-height:100%; margin:0; background:-webkit-linear-gradient(top,#e8e4dc,#f2f0eb); }
.page_list, .content { max-height:370px; box-sizing:border-box; padding:0; overflow-x:hidden; overflow-y:auto; -webkit-overflow-scrolling:touch }
#catalog_page { border-left:1px solid #CCC; z-index:28; position:absolute; top:0; width:200px; height:460px; background:white; -webkit-transition:-webkit-transform 0.1s ease-in;; -webkit-transform:translate3d(0,0,0); display:none; }
catalog_page is what sits outside the viewport, sliding into view only after someone does a gesture.
To reproduce:
1) Visit www.tekiki.com on your iPhone (not iPad). Scroll to the right, and you'll see how catalog_page extends the site's width, even though we fixed the body width.
Add html { overflow: hidden; } to your CSS and it should fix it.