$(document).ready(function () {
    var check = 0;
    var i;
    for (i = 0; i < 20; i++) {
        if ($(".a" + i + "").attr("id")) {
            check = $(".a" + i + "").attr("id").slice(1, 2);
        }
    }

    var loc = window.location;
    var pathName = loc.pathname.substring(loc.pathname.lastIndexOf('/') + 1, loc.pathname.length);
    switch (pathName) {
        case 'index.aspx':
            check = 0;
            break;

        case 'teleassistenza.aspx':
            check = 1;
            break;
        
        case 'contatti.aspx':
            check = 2;
            break;
    }


    var selected = check * ($("#b0").outerWidth());
    var position;

    $("#sprite").css({ backgroundPosition: '' + selected + 'px 4px' });

    $("#b0,#b1,#b2,#b3,#b4,#b5,#b6,#b7").css({ backgroundPosition: '0px 0px' }).mouseover(function () {
        position = $(this).attr("id").slice(1, 2) * ($("#b0").outerWidth())/*width of your list item*/;
        $("#sprite").stop().animate({ backgroundPosition: '' + position + 'px 4px' }, { duration: 300 });
    });

    $("#b0,#b1,#b2,#b3,#b4,#b5,#b6,#b7").css({ backgroundPosition: '0px 0px' }).mouseout(function () {
        $("#sprite").stop().animate({ backgroundPosition: '' + selected + 'px 4px' }, { duration: 300 });
    });



});