Frozen welcome screen

<style>

body::after {

  content: "";

  position: fixed;

  top: 0;

  left: 0;

  width: 100vw;

  height: 100vh;

  z-index: 9999;

background:

    url('https://media3.giphy.com/media/v1.Y2lkPTZjMDliOTUyMG9leGllaHp1ZW5tZG96OGh1NzQ2MXdsdnh5YTl5djV0NDQzbzBybyZlcD12MV9pbnRlcm5hbF9naWZfYnlfaWQmY3Q9cw/PRnJd9y9M4tRZgA7cW/giphy.gif')

    center center no-repeat, 

    repeating-linear-gradient(

      90deg,

      black,

      black 10px,

      white 10px,

      white 20px

    );

  background-size: cover, 40px 100%;

  animation: moveLines 5s linear infinite, fadeOut 2.6s forwards;

  pointer-events: none; /* lets clicks go through after fade */

}

/* Move the background stripes */

@keyframes moveLines {

  from {

    background-position: center center, 0 0;

  }

  to {

    background-position: center center, 100px 0;

  }

}

/* Fade out after 5s */

@keyframes fadeOut {

  0% {

    opacity: 1;

    visibility: visible;

  }

  90% {

    opacity: 1;

  }

  100% {

    opacity: 0;

    visibility: hidden;

  }

}

</style>