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                svg(width='0' height='0')
	filter#f(x='-50%' y='-200%' width='200%' height='500%' 
		//- create blurred copy
		feGaussianBlur(stdDeviation='.025 .2')
		//- bump up saturation of blurred copy
		feColorMatrix(type='saturate' values='1.3')
		//- slap original on top of blurred & saturated copy

//- no text duplication in the markup
h1 gradient text glow


                @property --k {
	syntax: '<number>';
	initial-value: 0;
	inherits: false

html, body { display: grid }

html { height: 100% }

body { background: #000 }

svg[height='0'] { position: absolute }

h1 { /* no pseudo needed */
	--k: 0;
	place-self: center;
				hsl(calc(var(--k)*1turn), 95%, 65%), 
				hsl(calc(var(--k)*1turn + 90deg), 95%, 65%)) text;
	color: transparent;
	font: 900 clamp(.875em, 7.25vw, 5em) arial black, sans-serif;
	filter: url(#f);
	text-align: center;
	text-transform: uppercase;
	/* needs support for animating custom properties */
	/* Firefox not quite there yet, but it's coming */
	animation: k 4s linear infinite

@keyframes k { to { --k: 1 } }