*{
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

html, body{
  height: 100%;
}

body{
  background-color: whitesmoke;
}


button.btn-show {
  position: absolute;
  left: 3em;
  top: 75%;
  background-color: whitesmoke;
  padding: 1em 5em;
  border: solid purple 2px;
  border-radius: 12px;
  color: purple;
  font-size: 2rem;
  cursor: pointer;
  
  transition: box-shadow 0.2s;
}

button.btn-show:hover{
  box-shadow: 0 0 6px 0.8px;
}

button.btn-show:active{
  color: white;
}

dialog.show{
  position: absolute;
  top: 50%;
  z-index: 2;
  padding: 5em;
  opacity: 1;
  color: black;
}

dialog{
  position: absolute;
  transform: translate(-50%, -50%);
  left: 50%;
  top: -300px;
  transition: all 0.3s;
}

dialog button{
  position: absolute;
  top: 2px;
  right: 8px;
  color: red;
  font-size: 2rem;  
  border:none;
  background-color: white;
  cursor: pointer;
}

div.container:has(.show){
  position: fixed;
  width: 100vw;
  z-index: 1;
  height: 100vh;
  background-color: black;
  opacity: 0.5;
}