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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <canvas id="rainbow"></canvas>

            
          
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              body {
  background: #13142b;
}

canvas {
  opacity: .6;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

            
          
!
            
              // VARS
const DPR = window.devicePixelRatio
const colors = [
  ['#EC008C', '#f957b6'],
  ['#EF4136', '#ff7972'],
  ['yellow', '#fff'],
  ['lime', '#7aff7a'],
  ['#27AAE1', '#5ec8f2'],
  ["#662D91", '#a158d8']
]
const tau = Math.PI * 2
const start = Math.PI // Start position
const finish = .5 // Finish (in % of circle "tau" basically ending at Math.PI * 2)
const inc = .007
const rainbowHeight = .5 // of view height
const arcStagger = .05 // in %
const sparklesInPerStripe = 3

let sparkles = []

// UTILS
const clamp = (min, max, val) => {
  return Math.min(Math.max(min, val), max)
}
const boolRandom = () => {
  return Math.round(Math.random()) ? false : true
}

// CANVAS
const sizeCanvas = () => {
  radius = clamp(15, 50, window.innerWidth / 60 / DPR)
  const canvas = document.getElementById('rainbow')
  canvas.width = window.innerWidth * DPR
  canvas.height = window.innerHeight * DPR
}

// SPARKLE PROPS
const addRandom = function (lineWidth) {
  return (boolRandom() ? -1 : 1) * Math.random() * lineWidth
}
const makeSparkle = ({cx, cy, radiusX, radiusY, endAngle, lineWidth, color}) => {
  return {
    x: cx + radiusX * Math.cos(endAngle) + addRandom(lineWidth), // stay out in front
    y: cy + radiusY * Math.sin(endAngle) + addRandom(lineWidth), 
    opacity: 1, 
    color, 
    rad: Math.max(radius * Math.random() * DPR, 15)
  }
}

// ANIMATE
function animate(percent = 0) {
  const doneAnimatingIn = percent >= finish + arcStagger * colors.length // animating in rainbow arcs
  
  let width = window.innerWidth * DPR
  let height = window.innerHeight * DPR
  
  const lineWidth = height * .5 / colors.length
  
  const cx = width / 2
  const startCy = height + lineWidth * rainbowHeight + (height - colors.length * lineWidth) / 3 // Possibly simplify this... but the math is good :) 
  
  const startRadiusX = width / 2 + colors.length * lineWidth * 2
  const startRadiusY = height

  let ctx = document.getElementById('rainbow').getContext('2d')
  ctx.clearRect(0, 0, width, height);  
  ctx.globalAlpha = 1;
  ctx.lineWidth = lineWidth
  
  for (let i = colors.length - 1; i > -1; i--) {
    const [colorLine, colorSparkle] = colors[i]
    
    const cy = startCy + i * (lineWidth / 2 - 1) // - 1 for overlap
    
    // Making these "concentric" ellipses
    const radiusX = startRadiusX - i * lineWidth / 2
    const radiusY = startRadiusY - i * lineWidth / 2
    
    const endAngle = tau * (percent - i * arcStagger) + start
    
    const angle = clamp(start, tau * finish + start, endAngle)
    
    // DRAW ONE OF OUR ELLIPSE LINES
    // - One color of our rainbow
    ctx.beginPath()
    ctx.shadowColor = colorLine
    ctx.strokeStyle = colorLine
    ctx.ellipse(
      cx,
      cy,
      radiusX,
      radiusY,
      0,
      start,
      angle,
      false
    )
    ctx.lineCap = "round"
    ctx.stroke()
    ctx.closePath()    
    
    
    if (!doneAnimatingIn) { 
      // ADD: Animating in sparkles, follow the start of each color
      for (let j = 0; j < sparklesInPerStripe; j++) {
        sparkles.push(
          makeSparkle({cx, cy, radiusX, radiusY, endAngle: angle, lineWidth, color: colorLine})
        )
      }
    } else {
      // ADD: Normal sparkles after animating in
      sparkles.push(makeSparkle({cx, cy, radiusX, radiusY, endAngle: Math.random() * Math.PI + Math.PI, lineWidth, color: boolRandom() ? '#fff' : colorSparkle}))
    }
  }
  
  // PAINT THE SPARKLES
  // and get next sparkles ready too
  const nextSparkles = []
  for (let i = 0, len = sparkles.length; i < len; i++) {
    const {x, y, opacity, color, rad} = sparkles[i]
    ctx.beginPath()
    ctx.globalAlpha = opacity;
    ctx.fillStyle = color
    ctx.arc(x - rad, y - rad, rad, 0, Math.PI / 2);
    ctx.arc(x - rad, y + rad, rad, 3 * Math.PI / 2, 2 * Math.PI);
    ctx.arc(x + rad, y + rad, rad, Math.PI, 3 * Math.PI / 2);
    ctx.arc(x + rad, y - rad, rad, Math.PI / 2, Math.PI);
    ctx.fill()
    
    // Sparkles we are keeping
    if (opacity > .2 && rad > .2) {
      nextSparkles.push({
        x,
        y,
        opacity: opacity - .03,
        rad: rad - .2,
        color
      })
    }
  }
  sparkles = nextSparkles
  
  if (!doneAnimatingIn) {
    // Animating in our rainbow
    requestAnimationFrame(function () {
      animate(percent + inc)
    })
  } else {
    // Resume sparkles on static rainbow
    requestAnimationFrame(function () {
      animate(finish + colors.length * arcStagger)
    })
  }
}

sizeCanvas()
requestAnimationFrame(function () {animate()})
window.addEventListener('resize', sizeCanvas)
            
          
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