SelectNav.js is a JavaScript plugin that lets you convert your website navigation into a select drop-down menu. Used together with media queries it helps you to create a space saving, responsive navigation for small screen devices.SelectNav.js adds a js class to the html element. Thanks to this, when JavaScript is disabled the default navigation will be visible. Selectnav.js works with every navigation in form of ul or ol lists that follow the example above.
Core Java Script Menus Responsive