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HTML 

              
                <section id="picker">
  <h1>HSL-picker</h1>
  <input type="range" min="0" step="0.1" max="360" id="hsl-h">
  <input type="range" min="0" step="0.1" max="100" id="hsl-s">
  <input type="range" min="0" step="0.1" max="100" id="hsl-l">
  <div id="sample"></div>
</section>
!

CSS 

              
                @use postcss-cssnext;

* {
  box-sizing: border-box;
}

:root {
  font-family: sans-serif;
}

body {
  margin: 0;
}

#picker {
  background-color: white;
  box-shadow: 0 .5rem 1rem -.25rem lightgray;
  margin: 2rem 0 1rem;
  padding: 1rem;
}

#picker h1 {
  font-weight: 100;
  line-height: 1;
  margin: 0 0 1rem;
  color: gray;
}

[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  background-color: currentColor;
  background-origin: content-box;
  background-repeat: no-repeat;
  border-radius: 2rem;
  display: block;
  color: inherit;
  height: 3rem;
  margin: 0 0 1rem;
  padding: 0;
  width: 100%;
}
[type="range"]:focus {
  outline: none;
}
[type="range"]::-moz-range-track {
  background-color: transparent;
}
[type="range"]::-webkit-slider-runnable-track {
  margin: 0 -1rem;
}
[type="range"]::-webkit-slider-thumb {
  appearance: none;
  background-color: transparent;
  border-radius: 100%;
  box-shadow:
    inset 0 0 0 .125rem currentColor,
    inset 0 0 0 .25rem white;
  height: 2rem;
  width: 2rem;
}
[type="range"]::-moz-range-thumb {
  background-color: transparent;
  border: 0;
  border-radius: 100%;
  box-shadow:
    inset 0 0 0 .125rem currentColor,
    inset 0 0 0 .25rem white;
  height: 2rem;
  width: 2rem;
}
#sample {
  border-radius: 2rem;
  height: 3rem;
  text-align: right;
  padding: .33rem 1rem;
  width: 100%;
}
#sample div {
  cursor: pointer;
  font-size: .75rem;
  font-weight: 100;
  line-height: 1.5em;
}
#sample div:hover {
  text-decoration: underline;
}
#sample .white {
  color: white;
}
#sample .black {
  color: black;
}

#hsl-h {
  background-image: linear-gradient(
    to right,
    #F00,
    #FF0,
    #0F0,
    #0FF,
    #00F,
    #F0F,
    #F00
  );
}

#hsl-s {
  background-image: linear-gradient(
    to right,
    #888,
    transparent
  );
}
#hsl-l {
  background-image: linear-gradient(
    to right,
    #000,
    transparent,
    #FFF
  );
}

@media screen and (min-width: 42rem) {
  #picker {
    width: 42rem;
    margin: 2rem auto 1rem;
  }
}
!

JS 

              
                console.clear();

var picker = {
  container: document.getElementById("picker"),
  sample: document.getElementById("sample")
};

var colors = {
  h: 320,
  s: 80,
  l: 50,
  textColor: function() {
    return this.l > 42 ?
      "black" :
      "white";
  },
  hueValue: function() {
    return Math.floor(this.h);
  },
  satValue: function() {
    return Math.floor(this.s) + "%";
  },
  lumValue: function() {
    return Math.floor(this.l) + "%";
  },
  getHSLString: function() {
    return "hsl(" + [
      colors.hueValue(),
      colors.satValue(),
      colors.lumValue()
    ].join(", ") + ")";
  },
  getHueLumString: function() {
    return "hsl(" +
      colors.hueValue() + ", 100%, " +
      colors.lumValue() + ")";
  },
  getHueSatString: function() {
    return "hsl(" +
      colors.hueValue() + ", " +
      colors.satValue() + ", 50%)";
  }
};

picker.sliders = Array.from(
  picker.container.querySelectorAll("input[type='range']")
);

picker.sliders.forEach(function(p, i) {
  p.addEventListener("input", handleSliderChange);
  initSlider(p);
});

function handleSliderChange() {
  var sliderType = this.id.split("hsl-")[1];
  if(sliderType === "h") {
    colors.h = this.value;
  } else if(sliderType === "s") {
    colors.s = this.value;
  } else if(sliderType === "l") {
    colors.l = this.value;
  }
  updateColors();
}

function fixChromeRepaintIssue(event) {
  var updateable = picker.sliders;
  if(event.type !== "mouseup") {
     updateable = picker.sliders.filter(function(el) {
      return el !== event.target;
    });
  }
  updateable.forEach(forceRepaint)
}

function forceRepaint(element) {  
  element.style.display='none';
  element.offsetHeight;
  element.style.display='';
}

function updateColors() {
  picker.sliders.forEach(updateColor);
}

function updateColor(color) {
  picker.sliders[0].style.color = colors.getHSLString();
  picker.sliders[1].style.color = colors.getHueLumString();
  picker.sliders[2].style.color = colors.getHueSatString();
  picker.sample.style.backgroundColor = colors.getHSLString();
  picker.sample.innerHTML = getColorValuesHTML();
}

function getColorValuesHTML() {
  return [
    "<div class=\"" + colors.textColor() + "\">",
    [
      colors.getHSLString(),
      window.getComputedStyle(picker.sliders[0]).color
    ].join("</div><div class=\"" + colors.textColor() + "\">"),
    "</div>"
  ].join("");
}

function initSlider(s) {
  if(s.id==="hsl-h") {
    s.value = colors.h;
  } else if(s.id ==="hsl-s") {
    s.value = colors.s;
  } else if(s.id ==="hsl-l") {
    s.value = colors.l;
  }
  updateColors();
}
!
999px

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