QWKbRgV

index.html

<!--  RGBA.js - my own super tiny webgl/fragment shader lib for codepen works
      more examples at - https://codepen.io/collection/AWEWzK -->

<script src="https://rawcdn.githack.com/strangerintheq/rgba/0.0.5/rgba.js"></script>
<a target="_blank" href="https://github.com/strangerintheq/rgba">RGBA.js</a>

qwkbrgv.markdown

QWKbRgV

A Pen by Stranger in the Q on CodePen.

License.

script.js

RGBA(`
        vec2 mirror(vec2 uv){
             const float count = 3.;
             float a = 3.1415/count/2.;
             float cs = cos(a), sn = sin(a);
             mat2 rot = mat2(cs, -sn, sn, cs); 
             for (float i = 0.0; i<count; i++ )
                 uv = abs(uv*rot);  
             return uv;
        }

        void main() {
            vec2 uv = gl_FragCoord.xy/resolution-0.5;
            uv.x *= resolution.x/resolution.y;
            
            for(float i=1.; i<21.; i++) {
                uv = mirror(uv);
                uv -= i*0.02;
            } 
            uv *= 21.;
            vec2 index = floor(uv);
            uv = fract(uv);
            vec3 c = vec3(
                smoothstep(0.1, 0.05, abs(fract(uv.x+time*0.2)-0.51)),
                smoothstep(0.1, 0.05, abs(fract(uv.x+time*0.2)-0.55)),
                smoothstep(0.1, 0.05, abs(fract(uv.x+time*0.2)-0.59))
            );
            gl_FragColor = vec4(vec3(c), 1.0);
        }
`)

style.css

a {
    position: fixed;
    left: calc(50% - 40px);
    font-size: 20px;
    color: white;
    mix-blend-mode: difference;
}