Why does jQuery .width() does not match css media query in mobile?

_x000D_ _x000D_ I would like to start of by stating I am asking why this is, not how get around it. I am well aware of these sources here: $(window).width() not the same as media query How to get screen width without (minus) scrollbar? Get the height and width of the browser viewport without scrollbars using jquery? CSS media queries and JavaScript window width do not match I have a media query implemented that is being called correctly everywhere: @media all and (max-width:620px), (max-device-width:620px){...} However, when I try to get the width through jQuery: alert($(window).width()); The value returns as 980. I have found that using .innerWidth() yields the same result as .width(). According to jQuery API $(window).width() returns the width of the browser viewport. So why is it different from the css media query?