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CSS

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JavaScript

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HTML

              
                <svg viewBox="11.8 9 16 22" class="mouse"><path d="M20,21l4.5,8l-3.4,2l-4.6-8.1L12,29V9l16,12H20z"></path></svg>

<h1>This demo is running infinitely</h1>
              
            
!

CSS

              
                svg {
  width: 40px;
  top: 0;
  left: 0;
  position: fixed;
}
h1 {
  position: fixed;
  top: 50%;
  left: 0;
  width: 100%;
  text-align: center;
  transform: translateY(-50%);
  opacity: 0.5;
}
              
            
!

JS

              
                // We retrieve the image from the DOM
const el = document.querySelector('.mouse');

// The render function is called on every frame
function render (a) {
  // The a variable is the amount of milliseconds since we started our script
  
  // Get a noise value based on the elapsed time
  // This noise algorithm is returning values between [-1, 1] so we need to map them to [0, 1] by adding one to the value and dividing it by 2
  const noiseX = (noise.simplex2(0, a*0.0005) + 1) / 2;
  // We get another noise value for the y axis but because we don't want the same value than x, we need to use another value for the first parameter
  const noiseY = (noise.simplex2(1, a*0.0005) + 1) / 2;
  
  // Convert the noise values from [0, 1] to the size of the window
  const x = noiseX * window.innerWidth;
  const y = noiseY * window.innerHeight;
  
  // Apply the x & y coordinates on our element
  el.style.transform = `translate(${x}px, ${y}px)`;
  
  // Call the render function once the browser is ready to make it an infinite loop
  requestAnimationFrame(render);
}

// Ask the browser to call render to start our animation
requestAnimationFrame(render);
              
            
!
999px

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