Java Script how to set cookie across website?

Question

I have made a cookie code but need the cvalue to be able to be accessed across the site. here is the write cookie code:

function setCookie(cname,cvalue) {
    var d = new Date();
    d.setTime(d.getTime() + (1*24*60*60*1000));
    var expires = "expires=" + d.toGMTString();
    document.cookie = cname+"="+cvalue+"; "+expires;
}

Then the receive cookie code:

function getCookie(cname) {
    var name = cname + "=";
    var ca = document.cookie.split(';');
    for(var i=0; i<ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1);
        if (c.indexOf(name) != -1) {
            return c.substring(name.length, c.length);
        }
    }
    return "";
}

Thanks for any help