body {
  font-family: Arial, sans-serif;
  text-align: center;
  background-color: #f4f4f4;
  background: url('https://images.unsplash.com/photo-1599466373322-7c1c53f5eec2') no-repeat center center fixed;
  margin: 0;
  padding: 0;
}

#menu {
  padding: 50px;
}

#menu h1 {
  font-size: 3rem;
  margin-bottom: 30px;
}

#menu button {
  font-size: 1.2rem;
  padding: 10px 30px;
  margin: 10px;
  cursor: pointer;
  background-color: #444;
  color: white;
  border: none;
  border-radius: 5px;
}

#menu button:hover {
  background-color: #666;
}

#game {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: 12vh;
}

#chessboard {
  display: grid;
  grid-template-columns: repeat(8, 10vh);
  grid-template-rows: repeat(8, 10vh);
  gap: 0;
 
  align-items: center;
    justify-content: center;
}

.square {
  width: 10vh;
  height: 10vh;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 7.5vh;
  cursor: pointer;
  border: 1px solid black;
}

.white {
  background-color: #eee;
  
}

.black {
  background-color: #666;
  
}

.valid-move {
  background-color: #00f4ff !important;
  box-shadow: inset 0 0 0 3px #007a94;
}

.selected {
  outline: 2px solid orange;
}