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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML
!

CSS 

              
                html,
body {
	width: 100%;
	height: 100%;
	overflow: hidden;
}

body {
	background: #f63;
}

.flake {
	position: absolute;
	width: 100px;
	height: 100px;
	background-size: cover;
}

.flake1 {
	background-image: url("https://assets.codepen.io/32887/flake1.svg");
}

.flake2 {
	background-image: url("https://assets.codepen.io/32887/flake2.svg");
}

.flake3 {
	background-image: url("https://assets.codepen.io/32887/flake3.svg");
}

.flake4 {
	background-image: url("https://assets.codepen.io/32887/flake4.svg");
}

body {
	background: #ed213a; /* fallback for old browsers */
	background: -webkit-linear-gradient(
		to right,
		#93291e,
		#ed213a
	); /* Chrome 10-25, Safari 5.1-6 */
	background: linear-gradient(
		to right,
		#93291e,
		#ed213a
	); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
}
!

JS 

              
                // full video tutorial at: https://www.youtube.com/watch?v=TAVVTRaXm5M

// click anywhere to pause / unpause

let numFlakes = 50;
let width = window.innerWidth;
let height = window.innerHeight;

function createFlake() {
	let flake = document.createElement("div");
	let flakeClass = "flake flake" + gsap.utils.random(1, 4, 1);
	flake.setAttribute("class", flakeClass);
	document.body.appendChild(flake);
	return flake;
}

function animateFlake(flake) {
	let scaleFactor = Power3.easeIn(Math.random());
	// change to easeOut for more larger flakes
	// let scaleFactor = Power3.easeOut(Math.random());
	let scale = gsap.utils.interpolate(0.3, 2, scaleFactor);
	let duration = gsap.utils.interpolate(2, 4, 1 - scaleFactor);
	let opacity = gsap.utils.interpolate(0.5, 1, scaleFactor);
	gsap.set(flake, {
		y: -200,
		x: gsap.utils.random(0, width),
		scale: scale,
		opacity: opacity
	});
	gsap.to(flake, {
		y: height + 200,
		x: "+=200",
		duration: duration,
		delay: "random(0,4)",
		ease: "none",
		rotation: "random(-60, 200)",
		onComplete: animateFlake,
		onCompleteParams: [flake]
	});
}

for (let i = 0; i < numFlakes; i++) {
	let flake = createFlake();
	animateFlake(flake);
}

// document.addEventListener("click", () =>
// 	gsap.globalTimeline.paused(!gsap.globalTimeline.paused())
// );

// full animated snow tutorial: https://www.youtube.com/watch?v=TAVVTRaXm5M

// new JavaScript? Don't worry, my FREE beginner GreenSock course GSAP 3 Express will get you up to speed quickly!
// https://www.creativecodingclub.com/courses/FreeGSAP3Express

// master the GreenSock Animation Platform at:
// https://www.creativecodingclub.com/bundles/creative-coding-club
!
999px

Console