jquery animate回调函数

[KOMO_TI]

$(document).ready(
    function () {
        var Rcolor = new Array("red", "green", "blue", "black", "orange", "#c7c7c7", "#7a378b", "yellow");
        var wid = new Array();
        var Wmax = window.innerWidth;
        for (var i = 0; i <= 7; i++) {
            var a = String(i);
            wid[i] = GetRandomNum(200, Wmax);
            $(".color" + a).css(
                {
                    "height": String(window.innerHeight / 20) + "px",
                    "width": String(wid[i]) + "px",
                    "background-color": Rcolor[i],
                    "opacity": .6,
                    "left": String(-wid[i]) + "px"
                }
                );
           
            $(".color" + a).delay(GetRandomNum(0, 1) * 1000).animate({ left: String(window.innerWidth) + "px" }, GetRandomNum(2, 6) * 1000, 'swing', function ()
            {
                AnimationContinue(this,-wid[i]);
            });
        }
        
    });

上面的代码我的wid已经有数据，为什么我animate的回掉函数使用时会是一个NAN

[KOMO_TI]

我颜色标记在代码里面好像直接显示代码了，那就直接看那几个<span>的地方吧