Bouhnosaure

$( ".contact-form" ).on( "submit", function( event ) {
  event.preventDefault();
  $.ajax({
		type: "POST",
		url: $( this ).attr('action'),
		data: $( this ).serialize(),
		dataType: "json",
		success: function(data) {
			alert('tout est ok !');
		},

Bouhnosaure

    function scrollToAnchor(id){
        var aTag = $("#"+id);
        $('html,body').animate({scrollTop: aTag.offset().top - 50},'slow');
    }