css glowing gradient loader ring/style.css
*
{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body
{
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: #000;
}
.loader
{
    position: relative;
    width: 150px;
    height: 150px;
    border-radius: 50%;
    background: linear-gradient(45deg, transparent, transparent 40%, #e5f403);
    animation: animate 2s linear infinite;

}
@keyframes animate
{
    0%
    {
        transform: rotate(0deg);
        filter: hue-rotate(0deg);
    }
    100%
    {
        transform: rotate(360deg);
        filter: hue-rotate(360deg);
    }
}
.loader::before
{
    content: '';
    position: absolute;
    top: 6px;
    left: 6px;
    right: 6px;
    bottom: 6px;
    background: #000;
    border-radius: 50%;
    z-index: 1000;
}
.loader::after
{
    content: '';
    position: absolute;
    left: 0px;
    right: 0px;
    top: 0px;
    bottom: 0px;
    background: #000;
    background: linear-gradient(45deg, transparent, transparent 40%, #e5f403);
    border-radius: 50%;
    z-index: 1000;
    z-index: 1;
    filter: blur(30px);
}