// Detect request animation frame
var scroll = window.requestAnimationFrame || // IE Fallback function(callback){ window.setTimeout(callback, 1000/1000)};
var elementsToShow = document.querySelectorAll('.show-on-scroll');
function loop() { elementsToShow.forEach(function (element) { if (isElementInViewport(element)) { element.classList.add('is-visible'); } else { element.classList.remove('is-visible'); } }); scroll(loop);
}
// Call the loop for the first time
loop();
// Helper function from: http://stackoverflow.com/a/7557433/274826
function isElementInViewport(el) { // special bonus for those using jQuery if (typeof jQuery === "function" && el instanceof jQuery) { el = el[0]; } var rect = el.getBoundingClientRect(); return ( (rect.top <= 0 && rect.bottom >= 0) || (rect.bottom >= (window.innerHeight || document.documentElement.clientHeight) && rect.top <= (window.innerHeight || document.documentElement.clientHeight)) || (rect.top >= 0 && rect.bottom <= (window.innerHeight || document.documentElement.clientHeight)) );
}