.glow-btn{background:linear-gradient(90deg,#0ff0 0%,#00ffff3d 50%,#0ff0 100%);position:relative;overflow:hidden}.glow-btn:before{content:"";opacity:0;background:linear-gradient(90deg,#0ff0 0%,#00ffff3d 50%,#0ff0 100%) 50%/200% 100%;transition:opacity .3s;position:absolute;inset:0}.glow-btn:hover:before{opacity:1;animation:1.5s ease-in-out infinite glowSweep}