void mainImage(out vec4 fragColor, in vec2 fragCoord)
{
    vec2 uv = fragCoord.xy / iResolution.xy;

    vec2 p = uv * 2.0 - 1.0;

    p.x *= iResolution.x / iResolution.y;

    float bass =
        0.5 +
        0.5 * sin(iTime * 2.5);

    float d = length(p);

    p += sin(p.yx * 8.0 + iTime) * bass * 0.12;

    float glow = 0.025 / abs(length(p) - 0.35);

    vec3 color = vec3(0.02, 0.04, 0.08);

    color += vec3(0.1, 0.7, 1.0) * glow * bass;
    color += vec3(1.0, 0.2, 0.7) * sin(d * 20.0 - iTime);

    fragColor = vec4(color, 1.0);
}