<div class="container">
  <div id="slider"></div>
</div>

.container {
  max-width: 500px;
  margin: 2rem;
}

const slider = document.getElementById('slider');

noUiSlider.create(slider, {
  start: [20, 80], 
  connect: true,
  range: {     
    'min': 0,
    'max': 100
  }
});

console.log(noUiSlider)