body {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: #10202b;
}

.tabs input {
  visibility: hidden;
  display: none;
}

.buttons {
  position: relative;
  display: flex;
  gap: 80px;
  padding: 30px 40px;
  border-bottom: 1px solid rgba(255,255, 255, 0.2);
  background: #182d3c;
  overflow: hidden;
  border-radius: 20px;  
}

.buttons label {
  width: 20%;
  font-size: 1.75em;
  -webkit-text-stroke: 1px #fff;
  color: transparent;
  opacity: 0.3;
  cursor: pointer;
  transition: 0.5s;  
}

.buttons label:hover {
  opacity: 1;
  filter: drop-shadow(0 0 10px #fff) drop-shadow(0 0 20px #fff);
}

.tabs input:nth-child(1):checked ~ .buttons label:nth-child(1), 
.tabs input:nth-child(2):checked ~ .buttons label:nth-child(2), 
.tabs input:nth-child(3):checked ~ .buttons label:nth-child(3), 
.tabs input:nth-child(4):checked ~ .buttons label:nth-child(4), 
.tabs input:nth-child(5):checked ~ .buttons label:nth-child(5)
{
  color: #fff; 
  opacity: 1;
  filter: drop-shadow(0 0 10px #fff) drop-shadow(0 0 20px #fff);
}

.underline {
  position: absolute;
  left: 0 ;
  bottom: 0;
  width: 20%;
  height: 5px;
  background: transparent;
  transition: 0.5s;
}

.underline::before {
  content: '';
  position:absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 100%;
  background: #fff;
  border-radius: 4px;
  filter: drop-shadow(0 0 10px #fff) drop-shadow(0 0 20px #fff) drop-shadow(0 0 30px #fff) drop-shadow(0 0 50px #fff);
}

.underline::after {
  content: '';
  position:absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 100%;
  background: #fff;
  border-radius: 4px;
  filter: drop-shadow(0 0 10px #fff) drop-shadow(0 0 20px #fff) drop-shadow(0 0 30px #fff) drop-shadow(0 0 50px #fff) blur(5px);
}


.tabs input:nth-child(1):checked ~ .buttons .underline {
  left:0;  
} 
.tabs input:nth-child(2):checked ~ .buttons .underline {
  left:20%;  
} 
.tabs input:nth-child(3):checked ~ .buttons .underline {
  left:40%;  
} 
.tabs input:nth-child(4):checked ~ .buttons .underline {
  left:60%;  
} 
.tabs input:nth-child(5):checked ~ .buttons .underline {
  left:80%;  
}