@font-face {
  font-family: 'Press Start 2P';
  src: url("../fonts/Press_Start_2P/PressStart2P-Regular.ttf") format("truetype");
  font-weight: normal;
  font-display: swap;
}
html, 
body {
  margin: 0;
  padding: 0;
  width: 100vw;
  height: 100vh;
}
.container {
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
}

.game-wrapper {
  position: relative;
  width: 288px;
  height: 512px;
  border: 1px solid grey;
}
.game-rules {
  margin: 0;
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  z-index: 4;
  font-family: 'Press Start 2P', cursive;
  font-size: 14px;
  text-align: center;
  line-height: 1.7;
  opacity: 1;
  visibility: visible;
}
.animate-game-rules {
  -webkit-animation: animateRules 2s forwards;
          animation: animateRules 2s forwards;
}
.start-screen {
  background-image: url(../images/flappy_bird_bg.png);
  background-position: center;
  background-repeat: no-repeat;
  background-size: contain;
  background-color: #70c5ce;
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 5;
}
.start-btn {
  padding: 15px 20px;
  outline: none;
  border: none;
  border-radius: 15px;
  background-color: #82e38c;
  font-family: 'Press Start 2P', cursive;
  font-size: 20px;
  letter-spacing: -1px;
  cursor: pointer;
  color: #000;

  -webkit-animation: btnScale 1s infinite;
          animation: btnScale 1s infinite;
}
.total-score {
  margin: 0;
  margin-top: 25px;
  font-family: 'Press Start 2P', cursive;
  font-weight: 600;
  font-size: 16px;
  color: #000;
}
.disable-dbl-tap-zoom {
  touch-action: manipulation;
}
@-webkit-keyframes btnScale {
  from {
    transform: scale(1);
  }
  50% {
    transform: scale(1.05);
  }
  to {
    transform: scale(1);
  }
}

@keyframes btnScale {
  from {
    transform: scale(1);
  }
  50% {
    transform: scale(1.05);
  }
  to {
    transform: scale(1);
  }
}

@-webkit-keyframes animateRules {
  from {
    opacity: 1;
    visibility: visible;
  }
  50% {
    opacity: 0.5;
    visibility: visible;
  }
  to {
    opacity: 0;
    visibility: hidden;
  }
}

@keyframes animateRules {
  from {
    opacity: 1;
    visibility: visible;
  }
  50% {
    opacity: 0.5;
    visibility: visible;
  }
  to {
    opacity: 0;
    visibility: hidden;
  }
}