外部Javascript加载但无法正常工作

Question

我有一个脚本，当脚本放在footer.php工作正常，但如果我把它放在外部.js文件是行不通的。加载OK但不起作用。

$(document).ready(function () { 
    $(function() { 
    !function(t){"use strict";function e(t,e,n,o,r){var i=Array.prototype.forEach,f=t instanceof Node?t:document.querySelector(t);if(!f)return!1;var s=f.querySelectorAll(e);if(0===s.length)return!1;n="number"==typeof n&&isFinite(n)&&Math.floor(n)===n?n:6,f.style.width="";var u=f.getBoundingClientRect().width,l=s[0].getBoundingClientRect().width+n,a=Math.max(Math.floor((u-n)/l),1),c=0;u=l*a+n+"px",f.style.width=u,f.style.position="relative";for(var d=[],p=[],h=0;a>h;h++)p.push(h*l+n),d.push(n);i.call(s,function(t){var e=d.slice(0).sort(function(t,e){return t-e}).shift();e=d.indexOf(e);var r=p[e],f=d[e],s=["webkitTransform","MozTransform","msTransform","OTransform","transform"];return t.style.position="absolute",o||i.call(s,function(e){t.style[e]="translate("+r+"px,"+f+"px)"}),d[e]+=t.getBoundingClientRect().height+n,c+=1,o?o(t,r,f,c):void 0});var m=d.slice(0).sort(function(t,e){return t-e}).pop();f.style.height=m+"px","function"==typeof r&&r(s)}"function"==typeof define&&define.amd?define(function(){return e}):"undefined"!=typeof module&&module.exports?module.exports=e:t.minigrid=e}(this);
    (function(){
        minigrid('.grid', '.grid-item');
        window.addEventListener('resize', function(){
            minigrid('.grid', '.grid-item');
        });
    })();
    });                                                                     
});