jQuery(document).ready(function($) {
  var array = ["#B51425", "#E84500", "#FFD615","#3BEBB1","#B52186"];
  var counter = 0;
  var nextColor;
  function bgchange() {
      console.log (counter);
      counter = (counter + 1) % array.length;
      nextColor = array[counter];
      $("section.banner").css("backgroundColor", nextColor);
  }
  setInterval(bgchange, 3000)
});