:root {
  --pageBlack: #262626;
  --pageYellow: #ffd83e;
  --pagePurple: #552b55;
  --pageRed: #E1332d;
  --pageGreen: #2ce771;
  --pageGrey: #212121;

}
body {
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  background-color: var(--pageGreen);
  font-family: sans-serif;
  overflow: hidden;
}
a {
  text-decoration: none;
  width: 160px;
  height: 60px;
  color: black;
  border: 2px solid black;
  text-align:center;
  line-height: 60px;
  font-size: 25px;
  position: relative;
  transition: all 0.4s;
  transition-delay: .1s;
}
a:hover {
  color:white;
  font-weight: 100;
}
a span {
  color: transparent;
  position: relative;
}
a span:before {
  content: 'B';
  position: absolute;
  color: black;
  transition: all 0.2s;
}
a:hover span:before {
  color: white;
  font-size: 80px;
  transform: translate(-65%, -10%) rotate(360deg);
}
a:before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: black;
  z-index: -1;
  opacity: 0;
  transition: all .8s;
  
}

a:hover:before {
  opacity: 1;
  transform: rotate(15deg);
}