*{
	margin: 0;
	padding: 0;

}
html, body{
	height: 100vh;
	font-family: sans-serif;
}

.header_top{
	background: #00795f;
	padding: 20px 0;
	text-align: center;
	color: white;
}

.container{
	margin: 0 auto;
}

.header_bottom{
	background: #2196F3;
	padding: 5px 0;
}


main{
	min-height: calc(100vh - 168px -149px);
}

.presentation_container{
    padding-bottom: 45%;
    padding-top: 35px;
    height: 0;
    overflow: hidden;
}

.presentation_container1{
    padding-bottom: 45%;
    padding-top: 4px;
    height: 0;
    overflow: hidden;
}

.presentation_container2{
    padding-bottom: 45%;
    padding-top: 4px;
    height: 0;
    overflow: hidden;
}

.presentation_container3{
    padding-bottom: 45%;
    padding-top: 4px;
    height: 0;
    overflow: hidden;
}

.clearfix:after{
	display: block;
	content: " ";
	clear: both;
}

.w3-border {
	display: block;
	margin-left: auto;
	margin-right: auto;
	margin-top: 10px;
	padding: 5px;
	width: 50%;
  }

nav ul {
	background-color:#2196F3;
	display:flex;
	flex-direction:column;
  }
  nav ul li{
	list-style-type: none;
  }
  nav ul li a{
	padding:.8rem 1rem;
	display:block;
	text-decoration: none;
	color: black;
  }
  nav ul li:hover{
	background:rgba(0,0,0, .25);
  }
  
  .arrow{
	font-family:FontAwesome;
	float:right;
  }
  .arrow-down::after{
	content:"\f107";
  }
  .arrow-right::after{
	content:"\f105";
  }
  
  
  @media only screen and (max-width:1024px) {
	.has-children ul li a{
	  padding-left:2rem;
	}
	
	.has-children ul .has-children ul a{
	  padding-left:3rem;
	}
	.arrow-down::after{
	  content:"\f107";
	}
  }
  
  @media only screen and (min-width:1024px) {

	nav ul{
	  flex-direction:row;
  /*     justify-content:flex-end; */
	}
	nav ul li{
	  position:relative;
	  flex:1 0 auto;
	  text-align:left;
	}
	.has-children ul, .has-children ul .has-children ul, .has-children ul .has-children ul .has-children ul{
	  display:none;
	  width:100%;
	  position:absolute;
	}
	.has-children ul .has-children ul{
	  left:100%;
	  top:0;
	}
	nav ul li:hover ul,  .has-children ul .has-children:hover ul, .has-children ul .has-children ul .has-children:hover ul{
	   display:flex;
	  flex-direction:column;
	}
	
  }

.footer{
	background: #00795f;
	padding:20px 0;
	margin-top: 100vh;
	text-align: center;
	clear: both;
	color: #ffff;
}