Delay the element on scroll

parallax.js

$.fn.parallax = function( options ) {
 
  if ( typeof options.opacity     === 'undefined' ) options.opacity = false;

  if ( typeof options.resistance  === 'undefined' ) options.resistance = 1;
 
  // determine the direction of the parallax thingy
  if ( typeof options.inverse     === 'undefined' ) options.inverse = true;
 
  var element = $( this );
 
  var total = 0;
 
  $( window ).on('scroll', function(){
    // calculate the offset
    total = window.pageYOffset + window.innerHeight;
 
    // scroll position
    var top = $( window ).scrollTop();

    // determine the orientation
    var sign = ( options.inverse ) ? -1 : 1;
 
    // get the page scroll offset
    var offset = ( window.pageYOffset * sign ) / options.resistance; 

    if( options.opacity ) {
      var opacity = ( 100 - top ) / 100;
      element.css( { 'opacity'   : opacity } );
    }
    
    // move the element
    element.css( { 'transform' : 'translate(0, ' + offset + 'px)'  } );
    
  });
 
  return $( this );
}

$(selector).parallax({inverse: true, opacity: true; resistance: 2});