.sidenav {
    height: 100%;
    width: 0;
    position: fixed;
    z-index: 1;
    top: 0;
    left: 0;
    background-color: #444;
    overflow-x: hidden;
    transition: 0.5s;
    z-index: 99999;
 }

.sidenav ul {
	width: 100%;
	display: block;
	top: calc(50% - 185px);
	position: relative;
	margin: 0;
	}
	
.sidenav ul li {
	float: none;
	text-align: left;
	width: 100%;
	display: block;
	}
	
.sidenav ul li a {
	text-decoration: none;
	padding: 15px 10px;
	}

.sidenav a.closebtn {
    position: absolute;
    top: 10px;
    right: 15px;
    font-size: 250%;
    margin-left: 50px;
    text-decoration: none;
}

div.sidenav_button_holder{
	position: fixed;
	left: 0;
	width: 40px;
	height: 100vh;
	z-index: 99999;
	transition: .5s;
	background: #444;
	padding: 0 3px;
	}
	
div.sidenav_button_holder span{
	cursor: pointer;
	position: relative;
	top: calc(50% - 20px);
	font-size: 170%;
	}
	
div.sidenav_push {
	position: relative;
	left: 40px;
	width: calc(100% - 40px);
	}

@media screen and (max-height: 450px) {
  .sidenav {padding-top: 15px;}
  .sidenav a {font-size: 18px;}
}

img.close_menu,
img.open_menu {
	width: 30px;
	}
	
img.open_menu {
	
	}
	
img.close_menu {
	
	}