* {
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
  }
  
  :root {
    --light-grey: #D3D6DA;
    --dark-grey: #787C7E;
    --yellow: #C9B458;
    --green: #6AAA64;
    --red: #d06767;
  }
  
  body {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
  }
  
  .flex-ctr {
    display: flex;
    justify-content: center;
    align-items: center;
  }
  
  h1 {
    margin: 0 5vmin 0 0;
    font-size: 5vmin;
  }
  
  header {
    margin-bottom: 5vmin;
  }
  
  #bad-word {
    display: none;
    font-size: 5vmin;
    color: red;
  }
  
  #play-again {
    display: none;
    padding: 1vmin;
  }
  
  #keyboard {
    margin-left: 5vmin;
    display: grid;
    grid-template-columns: repeat(5, 10vmin);
    grid-template-rows: repeat(6, 10vmin);
    gap: 1vmin;
  }
  
  #keyboard>button {
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 4.5vmin;
    background-color: var(--light-grey);
    border: none;
    border-radius: 1.3vmin;
  }
  
  #keyboard>button:last-child,
  #keyboard>button:nth-child(27) {
    grid-column: span 2;
  }
  
  #keyboard>button:last-child {
    font-size: 4vmin;
  }
  
  #board {
    display: grid;
    grid-template-columns: repeat(5, 10vmin);
    grid-template-rows: repeat(6, 10vmin);
    gap: 1vmin;
  }
  
  #board>div {
    display: flex;
    justify-content: center;
    align-items: center;
    border: .5vmin solid var(--light-grey);
    font-size: 4.5vmin;
    font-weight: bold;
    text-transform: uppercase;
  }
  
  .pop-in {
    animation-name: popIn;
    animation-duration: 100ms;
  }
  
  @keyframes popIn {
      from {
          transform: scale(0.8);
          opacity: 0
      }
  
      40% {
          transform: scale(1.1);
          opacity: 1
      }
  }