body {
  margin: unset;
  height: 100vh;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: horizontal;
  -webkit-box-direction: normal;
      -ms-flex-direction: row;
          flex-direction: row;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  background-color: #000;
  color: #FFF;
}

* {
  -webkit-box-sizing: border-box;
          box-sizing: border-box;
}

ul {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: horizontal;
  -webkit-box-direction: normal;
      -ms-flex-direction: row;
          flex-direction: row;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  list-style: none;
}
ul li {
  position: relative;
  overflow: hidden;
  border-bottom: 2px solid transparent;
  -webkit-transition: 360ms ease;
  transition: 360ms ease;
}
ul li span {
  padding: 2rem;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
}
ul li:hover {
  border-bottom-color: #007fde;
  background-color: rgba(255, 255, 255, 0.05);
}
ul li .glow {
  width: 10rem;
  height: 5rem;
  background: radial-gradient(circle, #007fde 0%, rgba(1, 227, 190, 0) 40%);
  position: absolute;
  left: 0;
  bottom: 0;
  -webkit-transform: translateX(-50%) translateY(50%);
          transform: translateX(-50%) translateY(50%);
  -webkit-transition: opacity 360ms ease;
  transition: opacity 360ms ease;
  -webkit-transition: left 60ms ease;
  transition: left 60ms ease;
  opacity: 0;
}
ul li.visible .glow {
  opacity: 1;
}