body{
  margin: 0;
  background-image: url("achtergrond.jpg");
  background-size: cover;         /* vult hele scherm */
  background-repeat: no-repeat;   /* geen herhaling */
  background-position: center;    /* mooi gecentreerd */
  background-attachment: fixed;  
  text-align: center;

}


.topnav {
  background-color: black;
  overflow: hidden;
  position: fixed;
  z-index: 1;
  width: 100%;
  top: 0;
}
a,img,button,div{
  user-select: none;
   -webkit-user-drag: none; /* Chrome, Safari */
  -khtml-user-drag: none;  /* oudere Konqueror */
  -moz-user-drag: none;    /* Firefox (werkt niet overal) */
  -o-user-drag: none;      /* Opera (ouder) */   
}
.normal-menu a {
  float:left;
  color: white;
  padding: 17px 17px;
  text-decoration: none;
  font-size: 24px;
}
.topnav h1{
   float:left;
  color: white;
  padding: 8px 15px;
  text-decoration: none;
  font-size: 18px;
}

.topnav a:hover{
 background-color: rgb(23, 205, 195);
}

.topnav a.active{
  background-color: aqua;
  color: white;
}
h1{
  text-align: center;
  color: white;
  padding: 10px;
  
}
 .Wisselknop {
 
  float: right;
  color: white;
  padding: 14px 14px;
  text-decoration: none;
  font-size: 25px;
  
}
.Wisselknop:hover {
    background-color: transparent !important; /* of wat je wilt */
    /* behoud originele kleur */
    cursor: pointer; /* blijft klikbaar */
}

 .topnav #hamburgermenu{
  display: none;
 margin-top: 62px;   
  background-color: black;
 
  width: 100%;

  text-align: start;
    height: auto;             
  z-index: 2;   
  
}#hamburgermenu a{
 color: white;
  text-decoration: none;
  font-size: 24px;
  width: 100%;
  display: block;
   z-index: 3; 
}
#hamburgermenu .Wisselknop{
  padding: 0px;
}
 .hamburgermenu-button{
 position: absolute;   
 top: 0px;     
  right: 0px;              
  display: none;
  justify-content: center;
  align-items: center;
  width: 60px;
  height: 100%;
  max-height: 62px;
  color: white;
  background-color: black;
  font-size: 30px;
  cursor: pointer;
  z-index: 999;              
} 

#hamburgermenu a:hover{
 background-color: rgb(23, 205, 195);

}

#hamburgermenu {
  display: none;
}

#hamburgermenu.active {
  display: block;
}
 
 
.hamburgermenu-button:hover{
 background-color: rgb(23, 205, 195);
}



.cards{
  
  height: 300px;
  max-width: 400px; /* maar niet breder dan 500px */
  text-align: center;
  
 width: 100%;
  margin-bottom: 50px;
  
}




.button1{
  outline: none;
margin-top: 10px;
width: auto;
border-radius: 10px;
  cursor: pointer;
  border: none;
  
}

.button1:hover{
  background-color: blue;
  color: white;

}

#container {

  position: absolute;
  top: 500px;
  width: 100%;
  min-height: 500px;
  background-color: rgb(42, 173, 167);
  border-radius: 50px;
  box-shadow: 5px 5px black;
  text-align: center;
  z-index: 0;
}

#home-blok{
  
  display: grid;
  width: 100%;
 
  height: auto;
  justify-self: center;
  justify-content: space-evenly;
  grid-template-columns: repeat(auto-fill, minmax(500px, 1fr));
 justify-items: center;
  
}



#voorstukje {
  position: relative;
  width: 100%;
 min-height: 75px;
  margin-top: 60px; /* in plaats van top: 5% */
  background-color: rgb(42, 173, 167);
border-radius: 8px;
  text-align: center;
  box-sizing: border-box;
}



img{
  width: 100%;
  height: 100%;

}

 
 
 



@media only screen and (max-width: 420px) {
.cards{
  max-width: 300px;
  height: 200px;
}
}



@media  only screen and (max-width: 720px  ){ 

#home-blok{
  grid-template-columns: 1fr;
}
 .normal-menu {
    display: none;
  }
  .hamburgermenu-button {
   
    display: flex;
  }
   .Wisselknop {
    display: none; /* of flex als je wilt */
  }
 
}@media (min-width: 721px) {
  #hamburgermenu {
    display: none !important;
  }
}