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

body,
html {
  width: 100%;
  height: 100%;
  font-family: "Press Start 2P", cursive;
  overflow: hidden;
  background: black;
}

.game-container {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 640px;
  height: 480px;
  overflow: hidden;
  background-color: black;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
}

.game-container img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  display: block;
  width: 100%;
  height: 100%;
}

.intro-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  background: black;
  z-index: 10;
}

#menu-screen {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  justify-content: center;
  align-items: center;
  display: flex;
}

#menu-screen .game-container {
  position: relative;
  top: auto;
  left: auto;
  transform: none;
  background-color: black;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

#menu-screen img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  display: block;
}

#start-btn {
  font-family: "Press Start 2P", cursive;
  font-size: 1rem;
  color: white;
  text-transform: uppercase;
  cursor: pointer;
  animation: blink 1s infinite;
  user-select: none;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.7);
  margin-top: 50px;
  padding: 5px 10px;
  position: absolute;
  bottom: 25%;
  left: 40%;
  transform: translateX(-50%);
}

@keyframes blink {
  0%,
  50%,
  100% {
    opacity: 1;
  }

  25%,
  75% {
    opacity: 0;
  }
}