.a2024{
    border: 3px solid #0000;
    border-radius: 1.5rem;
    background: linear-gradient(#131219, #131219) padding-box, linear-gradient(
            var(--angle),
            #7953cd,
            #ff8000,
            #00e054
        ) border-box;
    animation: 10s rotate ease-in-out infinite;
}

.a2024::before {
    z-index: -1;
    position: absolute;
    content:"";
    width:230px;
    height:230px;
    left:10px;
    top:0;
    background-image: linear-gradient(43deg, #4158D0 0%, #C850C0 46%, #FFCC70 100%); 
    filter: blur(20px);
    animation: 10s rotate ease-in-out infinite;
}

@keyframes rotate {
    to {
        --angle: 360deg;
    }
}

@property --angle {
    syntax: "<angle>";
    initial-value: 0deg;
    inherits: false;
}