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CSS

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HTML 

              
                <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/react/15.3.1/react.min.js"></script>  
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/react/15.3.1/react-dom.min.js"></script>
<script type="text/javascript" src="https://cdn.rawgit.com/konvajs/konva/0.14.0/konva.min.js"></script>
<script type="text/javascript" src="https://rawgit.com/lavrton/react-konva/v1.0.6/dist/react-konva.bundle.js"></script>
<script type="text/javascript" src="https://cdn.rawgit.com/bgrins/TinyColor/master/dist/tinycolor-min.js"></script>

<div id='container'></div>
!

CSS 

              
                body {
  background: gray;
}

#container {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

#background {
  display:flex;
  justify-content: center;
  align-items: center;
}

#stage {
  border: 5px solid darkgrey;
  border-radius: 10px;
  background-color: #EBEBEB;
  box-shadow: 0px 0px 20px black;
}
!

JS 

              
                const {Layer, Stage, Circle} = ReactKonva;

class ColorWheel extends React.Component {
  constructor(){
    super()
    this.state = {
      hue: 270,
      saturation: 100,
      light: 50,
      color: 'hsl(270,100%,50%)'
    }
    this.getHue = this.getHue.bind(this)
    this.getSaturation = this.getSaturation.bind(this)
    this.getLight = this.getLight.bind(this)
    this.hueDragBound = this.hueDragBound.bind(this)
    this.saturationDragBound = this.saturationDragBound.bind(this)
    this.lightDragBound = this.lightDragBound.bind(this)
    this.drawHueSlider = this.drawHueSlider.bind(this)
    this.drawSaturationSlider = this.drawSaturationSlider.bind(this)
    this.drawLightSlider = this.drawLightSlider.bind(this)
    this.drawSample = this.drawSample.bind(this)
  }
  
  drawSample(){
    var canvas = this.refs.layer.canvas;
    var ctx = canvas.getContext("2d");
    
    var color = tinycolor(this.state.color)
    var hex = '#' + color.toHex().toUpperCase()
    
    ctx.clearRect(95,85,110,130)
    ctx.fillStyle = 'lightgray'
    ctx.fillRect(95,85,110,130)
    ctx.fillStyle = this.state.color
    ctx.fillRect(100,90,100,100);
    
    ctx.font = "20px sans-serif";
    ctx.fillStyle = 'gray'
    ctx.fillText(hex, 107, 210);
  }
  
  getHue(x,y) {
    var angleDeg = Math.floor((Math.atan2(150 - y, 150 - x) * 180 / Math.PI) + 180);
    this.setState({
      hue: angleDeg,
      color: 'hsl('+angleDeg+','+this.state.saturation+'%,'+this.state.light+'%)'
    })
    this.drawSaturationSlider()
    this.drawLightSlider()
    this.drawSample()
  }
  
  getSaturation(x,y) {
    var offset = 50;
    var height = 200;
    var saturation = Math.round(-y/2 + 125)
    this.setState({
      saturation: saturation,
      color: 'hsl('+this.state.hue+','+saturation+'%,'+this.state.light+'%)'
    })
    this.drawHueSlider()
    this.drawLightSlider()
    this.drawSample()
  }
  
  getLight(x,y) {
    var offset = 50;
    var height = 200;
    var light = Math.round(-y/2 + 125)
    this.setState({
      light: light,
      color: 'hsl('+this.state.hue+','+this.state.saturation+'%,'+light+'%)'
    })
    this.drawHueSlider()
    this.drawSaturationSlider()
    this.drawSample()
  }
  
  saturationDragBound(pos){
    var top = 50
    var height = 200
    var bottom = height + top
    return {
      x: 365,
      y: pos.y < top? top : pos.y> bottom? bottom : pos.y 
    }
  }
  
  hueDragBound(pos){
    var x = 150;
    var y = 150;
    var radius = 110;
    
    if (pos.x === x && pox.y === y) return {x: x + radius, y: y}
    else {
        var scale = radius / Math.sqrt(Math.pow(pos.x - x, 2) + Math.pow(pos.y - y, 2));
      return {
        y: Math.round((pos.y - y) * scale + y),
        x: Math.round((pos.x - x) * scale + x)
      }
    }
  }
  
  lightDragBound(pos){
    var top = 50
    var height = 200
    var bottom = height + top
    return {
      x: 445,
      y: pos.y < top? top : pos.y> bottom? bottom : pos.y 
    }
  }
  
  drawLightSlider(){
    var canvas = this.refs.layer.canvas;
    var ctx = canvas.getContext("2d");
    ctx.clearRect(425,0,40,300)
    
    ctx.beginPath()
    ctx.arc(445,50,15,0,360,true)
    ctx.fillStyle = 'hsl('+this.state.hue+','+this.state.light+'%,100%)';
    // ctx.fillStyle = 'hsl(0,0%,100%)';
    ctx.fill()
    
    ctx.beginPath()
    ctx.arc(445,250,15,0,180,false)
    ctx.fillStyle = 'hsl('+this.state.hue+','+this.state.light+'%,0%)';
    // ctx.fillStyle = 'hsl(0,0%,0%)';
    ctx.fill()
    
    for(var i=0;i<=100;i++) {
      ctx.fillStyle = 'hsl('+this.state.hue+','+this.state.saturation+'%,'+i+'%)';
      // ctx.fillStyle = 'hsl(0,0%,'+i+'%)';
      ctx.fillRect(430,250-2*i,30,2);
    }
  }
  
  drawSaturationSlider(){
    var canvas = this.refs.layer.canvas;
    var ctx = canvas.getContext("2d");
    ctx.clearRect(350,0,40,300)
    ctx.beginPath()
    ctx.arc(365,50,15,0,360,true)
    // ctx.fillStyle = 'hsl('+this.state.hue+',100%,'+this.state.light+'%)';
    ctx.fillStyle = 'hsl('+this.state.hue+',100%,'+'50%)';
    ctx.fill()
    
    ctx.beginPath()
    ctx.arc(365,250,15,0,180,false)
    // ctx.fillStyle = 'hsl('+this.state.hue+',0%,'+this.state.light+'%)';
    ctx.fillStyle = 'hsl('+this.state.hue+',0%,'+'50%)';
    ctx.fill()
    
    for(var i=0;i<=100;i++) {
      // ctx.fillStyle = 'hsl('+this.state.hue+','+i+'%,'+this.state.light+'%)';
      ctx.fillStyle = 'hsl('+this.state.hue+','+i+'%,'+'50%)';
      ctx.fillRect(350,250-2*i,30,2);
    }
  }
  
  drawHueSlider(){
    var canvas = this.refs.layer.canvas;
    var ctx = canvas.getContext("2d");
    var x = 150;
    var y = 150;
    var radius = 125;
    var counterClockwise = false;
    
    ctx.clearRect(0,0,300,300)
    
    for(var angle=0; angle<360; angle++){
        var startAngle = (angle-1)*Math.PI/180;
        var endAngle = (angle+1) * Math.PI/180;
        ctx.beginPath();
        ctx.moveTo(x, y);
        ctx.arc(x, y, radius, startAngle, endAngle, counterClockwise);
        ctx.closePath();
        // ctx.fillStyle = 'hsl('+angle+','+this.state.saturation+'%,'+this.state.light+'%)';
      ctx.fillStyle = 'hsl('+angle+','+'100'+'%,'+'50'+'%)';
        ctx.fill();
    }

    ctx.beginPath();
    ctx.arc(x,y,radius,0,360)
    ctx.closePath();
    
    ctx.beginPath();
    ctx.arc(x,y,radius-30,0,360)
    ctx.closePath();
    ctx.fillStyle = '#EBEBEB'
    ctx.fill();
  }
  
  componentDidMount(){
    this.drawHueSlider()
    this.drawSaturationSlider()
    this.drawLightSlider()
    this.drawSample()
  }
  
  render(){
    
    return (
      <div id='background' style={{background: 'grey'}}>
      <div id='stage'>
      <Stage width={500} height={300} >
        <Layer ref='layer' />
        <Layer>
          <Selector getColor={this.getHue} color={this.state.color} dragBound={this.hueDragBound} x={150} y={40} />
        </Layer>
        <Layer>
          <Selector getColor={this.getSaturation} color={this.state.color} dragBound={this.saturationDragBound} x={365} y={50} />
        </Layer>
        <Layer>
          <Selector getColor={this.getLight} color={this.state.color} dragBound={this.lightDragBound} x={445} y={150} />
        </Layer>
      </Stage>
        </div>
        </div>
    )
  }
}

class Selector extends React.Component {
  constructor(){
    super()
    this.onDrag = this.onDrag.bind(this)
  }
  
  componentDidMount(){
    this.refs.circle.attrs.x = this.props.x
    this.refs.circle.attrs.y = this.props.y
  }
  
  onDrag(e){
    var _x = e.target.attrs.x
    var _y = e.target.attrs.y
    this.props.getColor(_x,_y)
  }

  render(){
    return (
      <Circle ref='circle'
        radius={20} stroke='white' strokeWidth={1} fill={this.props.color} shadowBlur={4} draggable
        onDragStart={this.onDrag} onDragMove={this.onDrag}
        dragBoundFunc={this.props.dragBound}
        transformsEnabled={'position'}
      />
    )
  }
}

ReactDOM.render(<ColorWheel />, document.getElementById('container'))
!
999px

Console