text: // Create an instance
  let wavesurfer;
  let wavesurferWithOptions;
  
  window.onload = function() {
      wavesurfer = WaveSurfer.create({
          container: document.querySelector('#waveform'),
          splitChannels: true
      });
  
      wavesurfer.on('error', function(e) {
          console.warn(e);
      });
  
      // Load audio from URL
      wavesurfer.load('../media/stereo.mp3');
  
      // Play/pause on button press
      document
          .querySelector('[data-action="play"]')
          .addEventListener('click', wavesurfer.playPause.bind(wavesurfer));
  
      // Drag'n'drop
      let toggleActive = function(e, toggle) {
          e.stopPropagation();
          e.preventDefault();
          toggle
              ? e.target.classList.add('wavesurfer-dragover')
              : e.target.classList.remove('wavesurfer-dragover');
      };
  
      let handlers = {
          // Drop event
          drop: function(e) {
              toggleActive(e, false);
  
              // Load the file into wavesurfer
              if (e.dataTransfer.files.length) {
                  wavesurfer.loadBlob(e.dataTransfer.files[0]);
              } else {
                  wavesurfer.fireEvent('error', 'Not a file');
              }
          },
  
          // Drag-over event
          dragover: function(e) {
              toggleActive(e, true);
          },
  
          // Drag-leave event
          dragleave: function(e) {
              toggleActive(e, false);
          }
      };
  
      let dropTarget = document.querySelector('#drop');
      Object.keys(handlers).forEach(function(event) {
          dropTarget.addEventListener(event, handlers[event]);
      });
  
      // WaveSurfer with options example
      wavesurferWithOptions = WaveSurfer.create({
          container: document.querySelector('#waveform-with-options'),
          splitChannels: true,
          splitChannelsOptions: {
              overlay: false,
              channelColors: {
                  0: {
                      progressColor: 'green',
                      waveColor: 'pink'
                  },
                  1: {
                      progressColor: 'orange',
                      waveColor: 'purple'
                  }
              },
              filterChannels: [],
              relativeNormalization: true
          }
      });
  
      wavesurferWithOptions.on('error', function(e) {
          console.warn(e);
      });
  
      // Load audio from URL
      wavesurferWithOptions.load('../media/stereo.mp3');
  
      // Play/pause on button press
      document
          .getElementById('play-button')
          .addEventListener('click', wavesurferWithOptions.playPause.bind(wavesurferWithOptions));
  
  };
  