$(document).ready(function() {
  var navDuration = 150; //time in miliseconds
  var navJumpHeight = "0.45em";
  $('#makesearch img').hover(function() {
    $(this).animate({ marginBottom: "-="+navJumpHeight }, navDuration);}, function() {$(this).animate({ marginBottom: "0px" }, navDuration);}
  );
});