*,
*::after,
*::before {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue';
}

a {
  -webkit-tap-highlight-color: transparent;
}

html {
  scroll-behavior: smooth;
  scrollbar-width: thin;
  scrollbar-color: white transparent;
}

body {
  height: 100vh;
  width: 100%;
  display: flex;
  flex-wrap: wrap;
  place-content: center;
  background-color: #000;
}

button {
  padding: 1rem;
  position: relative;
  width: 150px;
  height: 50px;
  border: none;
  background-color: #222;
  outline: none;

  &::before,
  &::after {
    content: '';
    position: absolute;
    inset: 0;
    background-image: linear-gradient(
      45deg,
      #7debf2,
      #60a4ff,
      #ffcc2f,
      #ef5734,
      #e4ad7a,
      #d770b2,
      #3d9c6c,
      #9ed478,
      #7debf2,
      #60a4ff,
      #ffcc2f,
      #ef5734,
      #e4ad7a,
      #d770b2,
      #3d9c6c,
      #9ed478
    );
    background-size: 400%;
    animation: move 10s linear infinite both;
  }

  &::after {
    filter: blur(20px);
    z-index: -1;
    transition: filter 0.5s ease-in-out;
  }

  span {
    position: absolute;
    display: block;
    inset: 2px;
    line-height: 48px;
    text-align: center;
    background-color: #222;
    color: #e9e9e9;
  }

  &:hover {
    &::after {
      filter: blur(40px);
    }
  }
}

@keyframes move {
  0% {
    background-position: 0 0;
  }
  50% {
    background-position: 300% 0;
  }
  100% {
    background-position: 0 0;
  }
}