!function(){"use strict";if("object"==typeof window)if("IntersectionObserver"in window&&"IntersectionObserverEntry"in window&&"intersectionRatio"in window.IntersectionObserverEntry.prototype)"isIntersecting"in window.IntersectionObserverEntry.prototype||Object.defineProperty(window.IntersectionObserverEntry.prototype,"isIntersecting",{get:function(){return this.intersectionRatio>0}});else{var t=function(t){for(var e=window.document,o=i(e);o;)o=i(e=o.ownerDocument);return e}(),e=[],o=null,n=null;s.prototype.THROTTLE_TIMEOUT=100,s.prototype.POLL_INTERVAL=null,s.prototype.USE_MUTATION_OBSERVER=!0,s._setupCrossOriginUpdater=function(){return o||(o=function(t,o){n=t&&o?l(t,o):{top:0,bottom:0,left:0,right:0,width:0,height:0},e.forEach((function(t){t._checkForIntersections()}))}),o},s._resetCrossOriginUpdater=function(){o=null,n=null},s.prototype.observe=function(t){if(!this._observationTargets.some((function(e){return e.element==t}))){if(!t||1!=t.nodeType)throw new Error("target must be an Element");this._registerInstance(),this._observationTargets.push({element:t,entry:null}),this._monitorIntersections(t.ownerDocument),this._checkForIntersections()}},s.prototype.unobserve=function(t){this._observationTargets=this._observationTargets.filter((function(e){return e.element!=t})),this._unmonitorIntersections(t.ownerDocument),0==this._observationTargets.length&&this._unregisterInstance()},s.prototype.disconnect=function(){this._observationTargets=[],this._unmonitorAllIntersections(),this._unregisterInstance()},s.prototype.takeRecords=function(){var t=this._queuedEntries.slice();return this._queuedEntries=[],t},s.prototype._initThresholds=function(t){var e=t||[0];return Array.isArray(e)||(e=[e]),e.sort().filter((function(t,e,o){if("number"!=typeof t||isNaN(t)||t<0||t>1)throw new Error("threshold must be a number between 0 and 1 inclusively");return t!==o[e-1]}))},s.prototype._parseRootMargin=function(t){var e=(t||"0px").split(/\s+/).map((function(t){var e=/^(-?\d*\.?\d+)(px|%)$/.exec(t);if(!e)throw new Error("rootMargin must be specified in pixels or percent");return{value:parseFloat(e[1]),unit:e[2]}}));return e[1]=e[1]||e[0],e[2]=e[2]||e[0],e[3]=e[3]||e[1],e},s.prototype._monitorIntersections=function(e){var o=e.defaultView;if(o&&-1==this._monitoringDocuments.indexOf(e)){var n=this._checkForIntersections,r=null,s=null;this.POLL_INTERVAL?r=o.setInterval(n,this.POLL_INTERVAL):(h(o,"resize",n,!0),h(e,"scroll",n,!0),this.USE_MUTATION_OBSERVER&&"MutationObserver"in o&&(s=new o.MutationObserver(n)).observe(e,{attributes:!0,childList:!0,characterData:!0,subtree:!0})),this._monitoringDocuments.push(e),this._monitoringUnsubscribes.push((function(){var t=e.defaultView;t&&(r&&t.clearInterval(r),c(t,"resize",n,!0)),c(e,"scroll",n,!0),s&&s.disconnect()}));var u=this.root&&(this.root.ownerDocument||this.root)||t;if(e!=u){var a=i(e);a&&this._monitorIntersections(a.ownerDocument)}}},s.prototype._unmonitorIntersections=function(e){var o=this._monitoringDocuments.indexOf(e);if(-1!=o){var n=this.root&&(this.root.ownerDocument||this.root)||t,r=this._observationTargets.some((function(t){var o=t.element.ownerDocument;if(o==e)return!0;for(;o&&o!=n;){var r=i(o);if((o=r&&r.ownerDocument)==e)return!0}return!1}));if(!r){var s=this._monitoringUnsubscribes[o];if(this._monitoringDocuments.splice(o,1),this._monitoringUnsubscribes.splice(o,1),s(),e!=n){var h=i(e);h&&this._unmonitorIntersections(h.ownerDocument)}}}},s.prototype._unmonitorAllIntersections=function(){var t=this._monitoringUnsubscribes.slice(0);this._monitoringDocuments.length=0,this._monitoringUnsubscribes.length=0;for(var e=0;e=0&&m>=0&&{top:c,bottom:a,left:f,right:d,width:g,height:m}||null),!v)break;_=_&&p(_)}return v}},s.prototype._getRootRect=function(){var e;if(this.root&&!d(this.root))e=u(this.root);else{var o=d(this.root)?this.root:t,n=o.documentElement,i=o.body;e={top:0,left:0,right:n.clientWidth||i.clientWidth,width:n.clientWidth||i.clientWidth,bottom:n.clientHeight||i.clientHeight,height:n.clientHeight||i.clientHeight}}return this._expandRectByRootMargin(e)},s.prototype._expandRectByRootMargin=function(t){var e=this._rootMarginValues.map((function(e,o){return"px"==e.unit?e.value:e.value*(o%2?t.width:t.height)/100})),o={top:t.top-e[0],right:t.right+e[1],bottom:t.bottom+e[2],left:t.left-e[3]};return o.width=o.right-o.left,o.height=o.bottom-o.top,o},s.prototype._hasCrossedThreshold=function(t,e){var o=t&&t.isIntersecting?t.intersectionRatio||0:-1,n=e.isIntersecting?e.intersectionRatio||0:-1;if(o!==n)for(var i=0;i