precision mediump float;

#endif

​

uniform vec2 u_resolution;

uniform float u_time;

​

void main() {

  vec2 coord = 3.0 * (gl_FragCoord.xy / u_resolution.xy);

  float color = 0.0;

  color += sin(coord.x * 6.0 + sin(u_time + coord.y * 90.0 + cos(coord.x * 30.0 + u_time * 2.0))) * 0.5;

   color += cos(coord.y * 60.0 + cos(u_time + coord.x * 20.0 + sin(coord.y * 10.0 + u_time * 3.0))) * 0.5;

  gl_FragColor = vec4(vec3(color, color + coord.x, color + coord.y), 1.0);

}