body {
  margin: 0;
  padding: 0;
}
.center {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: #262626;
  font-size: 48px;
  font-family: sans-serif;
  margin: 0;
  padding: 0 0 6px;
}
.center::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 6px;
  background: #262626;
  border-bottom: 6px solid #ffeb3b; 
  transition: 2s;
}
.center:hover::before {
  width: 100%;
}
.center:hover::after {
  width: 50%;
}
.center::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 25%;
  width: 0;
  height: 6px;
  background: #262626;
  transition: .5s;
  transition-delay: .5s;
}
.center span {
  display: block;
  position: absolute;
  bottom: 0;
  left: 25%;
  width: 0;
  height: 6px;
  background: #f00;
  /* transition: .5s; */
}