Ghost theme (MIT license)
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/* BackgroundCheck
http://kennethcachia.com/background-check
v1.2.2 */
!function(a,b){"function"==typeof define&&define.amd?define(b):a.BackgroundCheck=b(a)}(this,function(){"use strict";function a(a){if(void 0===a||void 0===a.targets)throw"Missing attributes";H.debug=d(a.debug,!1),H.debugOverlay=d(a.debugOverlay,!1),H.targets=g(a.targets),H.images=g(a.images||"img",!0),H.changeParent=d(a.changeParent,!1),H.threshold=d(a.threshold,50),H.minComplexity=d(a.minComplexity,30),H.minOverlap=d(a.minOverlap,50),H.windowEvents=d(a.windowEvents,!0),H.maxDuration=d(a.maxDuration,500),H.mask=d(a.mask,{r:0,g:255,b:0}),H.classes=d(a.classes,{dark:"background--dark",light:"background--light",complex:"background--complex"}),void 0===B&&(h(),B&&(C.style.position="fixed",C.style.top="0px",C.style.left="0px",C.style.width="100%",C.style.height="100%",window.addEventListener(G,x.bind(null,function(){k(),w()})),window.addEventListener("scroll",x.bind(null,w)),k(),w()))}function b(){B=null,C=null,D=null,H={},E&&clearTimeout(E)}function c(a){z("debug")&&console.log(a)}function d(a,b){return e(a,typeof b),void 0===a?b:a}function e(a,b){if(void 0!==a&&typeof a!==b)throw"Incorrect attribute type"}function f(a){for(var b,d,e=[],f=0;f<a.length;f++)if(b=a[f],e.push(b),"IMG"!==b.tagName){if(d=window.getComputedStyle(b).backgroundImage,d.split(/,url|, url/).length>1)throw"Multiple backgrounds are not supported";if(!d||"none"===d)throw"Element is not an <img> but does not have a background-image";e[f]={img:new Image,el:e[f]},d=d.slice(4,-1),d=d.replace(/"/g,""),e[f].img.src=d,c("CSS Image - 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