app.js

//https://www.w3schools.com/howto/tryit.asp?filename=tryhow_css_smooth_scroll_jquery
$(document).ready(function(){ 
  // Add smooth scrolling to all links
  $("a").on('click', function(event) {

    // Make sure this.hash has a value before overriding default behavior
    if (this.hash !== "") {
      // Prevent default anchor click behavior
      event.preventDefault();

      // Store hash
      var hash = this.hash;

      // Using jQuery's animate() method to add smooth page scroll
      // The optional number (800) specifies the number of milliseconds it takes to scroll to the specified area
      $('html, body').animate({
        scrollTop: $(hash).offset().top
      }, 2000, function(){
   
        // Add hash (#) to URL when done scrolling (default click behavior)
        //window.location.hash = hash;
      });
    } // End if
  });
});