<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport"
content="width=device-width,user-scalable=0, initial-scale=1.0，maximum-scale=1.0，minimum-scale=1.0">
<title>Document</title>
<style>
* {
padding: 0;
margin: 0;
background-color: #000;
}
.box {
display: grid;
place-content: center;
height: 100vh;
}
button {
position: relative;
margin: 15px;
height: 60px;
width: 300px;
border-radius: 50px;
border: none;
outline: none;
text-transform: uppercase;
background-color: #111;
cursor: pointer;
color: white;
}
button:first-child:hover {
background: linear-gradient(90deg, #03a9f4, #f441a5, #ffeb3b, #03a9f4);
background-size: 400%;
}
button:last-child:hover {
background: linear-gradient(90deg, #fa7199, #f5ce62, #e43603, #fa7199);
background-size: 400%;
}
button:first-child:before,
button:last-child:before {
content: '';
position: absolute;
background: inherit;
top: -5px;
right: -5px;
bottom: -5px;
left: -5px;
border-radius: 50px;
filter: blur(10px);
opacity: 0;
transition: opacity .5s;
}
button:first-child:hover:before,
button:last-child:hover:before {
opacity: 1;
z-index: -1;
}
button:hover {
z-index: 1;
animation: glow 5s linear infinite;
}
@keyframes glow {
0% {
background-position: 0%;
}
100% {
background-position: 400%;
}
}
</style>
</head>
<body>
<div class="box">
<button>button</button>
<button>button</button>
</div>
</body>
</html>
