@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@200&display=swap');

body{
	padding:3px;
	background-color: #202020;
	font-family: 'Nunito', sans-serif;
}

.kacheln {
	width: 100px;
	height: 100px;
	display: inline-block;
	color: cadetblue;
	background-color: antiquewhite;
}

@media screen and (max-width: 800px){
	#menu {position:relative}
	#menu ul {background:#111;position:absolute;top:100%;right:0;left:0;z-index:3;height:auto;display:none}
	#menu ul.sub-menus {width:100%;position:static;}
	#menu ul.sub-menus a {padding-left:30px;}
	#menu li {display:block;float:none;width:auto;}
	#menu input, #menu label {position:absolute;top:0;left:0;display:block}
	#menu input {z-index:4}
	#menu input:checked + label {color:white}
	#menu input:checked + label:before {content:"\00d7"}
	#menu input:checked ~ ul {display:block}
}

 #flex-container {
   display: -webkit-flex;
   display: -ms-flex;
   display: flex;
   -webkit-flex-wrap: wrap;
   -ms-flex-wrap: wrap;
   flex-wrap: wrap;
}
.panel-test2 {
  display: -webkit-flex; 
  display: -ms-flexbox; 
  display: flex;

  width: 30%;
  padding: 20px;
  float: left;
  margin: 10px;
  border: 1px solid #aaa;
}