Красивый неоновый hover-эффект при наведении на кнопку

@import url("https://fonts.googleapis.com/css2?family=Questrial&display=swap");
/************************************************
1.	BODY
************************************************/
body {
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  min-height: 100vh;
  background-color: #050f1a;
  font-family: "Questrial", Impact, sans-serif;
}
/************************************************
2.	LIEN et BOUTON
************************************************/
a {
  position: relative;
  display: inline-block;
  padding: 15px 30px;
  color: #00fff6;
  text-transform: uppercase;
  letter-spacing: 3px;
  text-decoration: none;
  font-size: 30px;
  overflow: hidden;
  transition: 0.2s;
}
a:visited {
  color: #00fff6;
}
a:hover {
  color: #050f1a;
  background: #00fff6;
  border-radius: 3px;
  box-shadow: 0 0 10px #00fff6, 0 0 40px #00fff6, 0 0 80px #00fff6;
  transition-delay: 600ms;
}
a span {
  position: absolute;
  display: block;
}
/************************************************
3.	NEON DU HAUT
************************************************/
a span:nth-child(1) {
  top: 0;
  left: -100%;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, #00fff6);
}
a:hover span:nth-child(1) {
  left: 100%;
  transition: 600ms;
}
/************************************************
4.	NEON DU BAS
************************************************/
a span:nth-child(3) {
  bottom: 0;
  right: -100%;
  width: 100%;
  height: 2px;
  background: linear-gradient(270deg, transparent, #00fff6);
}
a:hover span:nth-child(3) {
  right: 100%;
  transition: 1s;
  transition-delay: 250ms;
}
/************************************************
5.	NEON DE DROITE
************************************************/
a span:nth-child(2) {
  top: -100%;
  right: 0;
  width: 2px;
  height: 100%;
  background: linear-gradient(180deg, transparent, #00fff6);
}
a:hover span:nth-child(2) {
  top: 100%;
  transition: 1s;
  transition-delay: 100ms;
}
/************************************************
5.	NEON DE GAUCHE
************************************************/
a span:nth-child(4) {
  bottom: -100%;
  left: 0;
  width: 2px;
  height: 100%;
  background: linear-gradient(360deg, transparent, #00fff6);
}
a:hover span:nth-child(4) {
  bottom: 100%;
  transition: 1s;
  transition-delay: 450ms;
}