var changeStyleOnElements=function(n,t){var i=document.querySelectorAll(n);Array.prototype.forEach.call(i,function(n){n.style.display=t})},hideElements=function(n){n?changeStyleOnElements("nav, header, .scroll-button","none"):(changeStyleOnElements("nav, header","block"),changeStyleOnElements(".scroll-button","inline-block"))},changeFullscreen=function(){document.fullscreen|document.webkitIsFullScreen|document.mozFullScreen|document.webkitIsFullScreen|document.msFullscreenElement?hideElements(!0):hideElements(!1)};document.onwfullscreenchange=changeFullscreen;document.onwebkitfullscreenchange=changeFullscreen;document.onmozfullscreenchange=changeFullscreen;document.MSFullscreenChange=changeFullscreen