<main>
  <h1>Happy Holidays!</h1>
</main>
<div id="snow-container" title="Click anywhere to remove snow">
</div>
<footer>
  Pen by <a href="https://www.jemimaabu.com" target="_blank" rel="noopener">Jemima Abu ☃️</a>
</footer>

@import url("https://fonts.googleapis.com/css2?family=Pacifico&display=swap");

* {
  box-sizing: border-box;
}

body {
  margin: 0;
}

main {
  background: linear-gradient(to bottom, #2d91c2 0%, #1e528e 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Pacifico", cursive;
  height: 100vh;
  padding: 20px;
  text-align: center;
}

h1 {
  color: white;
}

#snow-container {  
  height: 100vh;
  overflow: hidden;
  position: absolute;
  top: 0;
  transition: opacity 500ms;
  width: 100%;
}

.snow {
  animation: fall ease-in infinite, sway ease-in-out infinite;
  color: skyblue;
  position: absolute;
}

footer {
  background-color: #ffdfb9;
  bottom: 0;
  font-family: sans-serif;
  padding: 1rem;
  text-align: center;
  width: 100%;
}

footer a {
  color: inherit;
  text-decoration: none;
}

footer .heart {
  color: #dc143c;
}

@keyframes fall {
  0% {
    opacity: 0;
  }
  50% {
    opacity: 1;
  }
  100% {
    top: 100vh;
    opacity: 1;
  }
}

@keyframes sway {
  0% {
    margin-left: 0;
  }
  25% {
    margin-left: 50px;
  }
  50% {
    margin-left: -50px;
  }
  75% {
    margin-left: 50px;
  }
  100% {
    margin-left: 0;
  }
}

const snowContainer = document.getElementById("snow-container");
const snowContent = ['&#10052', '&#10053', '&#10054']

const random = (num) => {
  return Math.floor(Math.random() * num);
}

const getRandomStyles = () => {
  const top = random(100);
  const left = random(100);
  const dur = random(10) + 10;
  const size = random(25) + 25;
  return `
    top: -${top}%;
    left: ${left}%;
    font-size: ${size}px;
    animation-duration: ${dur}s;
  `;
}

const createSnow = (num) => {
  for (var i = num; i > 0; i--) {
    var snow = document.createElement("div");
    snow.className = "snow";
    snow.style.cssText = getRandomStyles();
    snow.innerHTML = snowContent[random(3)]
    snowContainer.append(snow);
  }
}

const removeSnow = () => {
  snowContainer.style.opacity = "0";
  setTimeout(() => {
    snowContainer.remove()
  }, 500)
}

window.addEventListener("load", () => {
  createSnow(30)
  setTimeout(removeSnow, (1000 * 60))
});

window.addEventListener("click", () => {
  removeSnow()
});