<a href="#" id="btn-gra" class="btn-gra">hover me</a>
body{
background-color: #000;
margin: 0;
padding: 0;
}
#btn-gra{
position: absolute;
top: 50%;
left: 50%;
height: 60px;
width: 200px;
transform: transfer(-50%, -50%);
font-family: sans-serif;
text-align: center;
text-decoration: none;
line-height: 60px;
color: #fff;
text-transform: uppercase;
font-size: 24px;
box-sizing: border-box;
background: linear-gradient(90deg, #03a9f4, #f441a5, #ffeb3b, #03a9f4);
background-size: 400%;
border-radius: 30px;
z-index: 1;
}
#btn-gra:hover{
color: #fff;
text-decoration: none;
animation: animate 8s linear infinite;
}
@keyframes animate
{
0%
{
background-position: 0%;
}
100%
{
background-position: 400%;
}
}
#btn-gra:before{
content: '';
position: absolute;
top: -5px;
left: -5px;
bottom: -5px;
right: -5px;
z-index: -1;
background: linear-gradient(90deg, #03a9f4, #f441a5, #ffeb3b, #03a9f4);
background-size: 400%;
border-radius: 40px;
filter: blur(20px);
opacity: 0;
transition: 0.5s;
}
#btn-gra:hover:before{
filter: blur(20px);
opacity: 1;
animation: animate 8s linear infinite;
}
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