body {
  margin:0;
  padding:0;
  box-sizing:border-box;
}
#darkmode {
    display:flex;
    justify-content:center;
    align-items:center;
    flex-direction:column;
    justify-content:space-around;
    align-items:center;
    background-color:grey;
    height:500px;
    width:500px;
}
.container {
    height:15em;
    width:15em;
    background-color:black;
    border:2px solid black;
    box-shadow:5px 5px 7px 5px #404040;
    display:flex;
    flex-direction:column;
    justify-content:flex-end;
    align-items:flex-end;  
}
.children {
    height:3em;
    width:3em;    
}
.blue {
    background-color:blue;
}
.white {
    background-color:green;
    align-self:flex-start;
}
.red {
    background-color:red;
}
button {
    height:40px;
    width:100px;
}
.dark-mode .container {
    background-color:white;
}
.dark-mode #darkmode {
    background-color:black;
}