shadow animation on Drift Diary Title

gistfile1.js

var alphaCounter = 1;
var countDirection = 1;
var mainStyleSheet = document.styleSheets[0];
function getShadowCssText(alphaValue) {
	return "#banner-header {text-shadow: 4px 4px 4px rgba(105, 105, 105, " + alphaValue + ") !important;}"
}

function timeout_trigger() {
	if( alphaCounter < 0 || alphaCounter > 20 ) {
		countDirection *= -1;
	}
	alphaCounter += countDirection;

	mainStyleSheet.deleteRule(0)
	mainStyleSheet.insertRule(getShadowCssText(alphaCounter / 10), 0)
	setTimeout('timeout_trigger()', 100);
}

function timeout_init() {
	mainStyleSheet.insertRule(getShadowCssText(0), 0)
    timeout = setTimeout('timeout_trigger()', 100);
}

timeout_init();