https://www.cyberlink.com/prog/learning-center/js/jquery.sticky.js

1(function(d){"function"===typeof define&&define.amd?define(["jquery"],d):"object"===typeof module&&module.exports?module.exports=d(require("jquery")):d(jQuery)})(function(d){var q=Array.prototype.slice,u=Array.prototype.splice,n={topSpacing:0,bottomSpacing:0,className:"is-sticky",wrapperClassName:"sticky-wrapper",center:!1,getWidthFrom:"",widthFromWrapper:!0,responsiveWidth:!1},p=d(window),v=d(document),k=[],r=p.height(),l=function(){for(var b=p.scrollTop(),e=v.height(),f=e-r,f=b>f?f-b:0,c=0,h=k.length;c<
2h;c++){var a=k[c],g=a.stickyWrapper.offset().top-a.topSpacing-f;a.stickyWrapper.css("height",a.stickyElement.outerHeight());if(b<=g)null!==a.currentTop&&(a.stickyElement.css({width:"",position:"",top:""}),a.stickyElement.parent().removeClass(a.className),a.stickyElement.trigger("sticky-end",[a]),a.currentTop=null);else{g=e-a.stickyElement.outerHeight()-a.topSpacing-a.bottomSpacing-b-f;g=0>g?g+a.topSpacing:a.topSpacing;if(a.currentTop!==g){var m;a.getWidthFrom?m=d(a.getWidthFrom).width()||null:a.widthFromWrapper&&
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4[a]);a.currentTop=g}var l=a.stickyWrapper.parent();a.stickyElement.offset().top+a.stickyElement.outerHeight()>=l.offset().top+l.outerHeight()&&a.stickyElement.offset().top<=a.topSpacing?a.stickyElement.removeClass("sticky").css("position","absolute").css("top","").css("bottom",0):a.stickyElement.addClass("sticky").css("position","fixed").css("top",g).css("bottom","")}}},t=function(){r=p.height();for(var b=0,e=k.length;b<e;b++){var f=k[b],c=null;f.getWidthFrom?f.responsiveWidth&&(c=d(f.getWidthFrom).width()):
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6b;e.stickyWrapper=c;e.currentTop=null;k.push(e);h.setWrapperHeight(this);h.setupChangeListeners(this)})},setWrapperHeight:function(b){b=d(b);var e=b.parent();e&&e.css("height",b.outerHeight())},setupChangeListeners:function(b){window.MutationObserver?(new window.MutationObserver(function(e){(e[0].addedNodes.length||e[0].removedNodes.length)&&h.setWrapperHeight(b)})).observe(b,{subtree:!0,childList:!0}):(b.addEventListener("DOMNodeInserted",function(){h.setWrapperHeight(b)},!1),b.addEventListener("DOMNodeRemoved",
7function(){h.setWrapperHeight(b)},!1))},update:l,unstick:function(b){return this.each(function(){for(var b=d(this),f=-1,c=k.length;0<c--;)k[c].stickyElement.get(0)===this&&(u.call(k,c,1),f=c);-1!==f&&(b.unwrap(),b.css({width:"",position:"",top:"","float":""}))})}};window.addEventListener?(window.addEventListener("scroll",l,!1),window.addEventListener("resize",t,!1)):window.attachEvent&&(window.attachEvent("onscroll",l),window.attachEvent("onresize",t));d.fn.sticky=function(b){if(h[b])return h[b].apply(this,
8q.call(arguments,1));if("object"!==typeof b&&b)d.error("Method "+b+" does not exist on jQuery.sticky");else return h.init.apply(this,arguments)};d.fn.unstick=function(b){if(h[b])return h[b].apply(this,q.call(arguments,1));if("object"!==typeof b&&b)d.error("Method "+b+" does not exist on jQuery.sticky");else return h.unstick.apply(this,arguments)};d(function(){setTimeout(l,0)})});