* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  margin: 0;
  padding: 20px;

  display: flex;
  align-items: center;
  justify-content: center;

  font-family: Arial, sans-serif;
  background: #f4f1e8;
}

.jogo {
  width: min(100%, 700px);
  padding: 30px;

  text-align: center;

  background: white;
  border-radius: 24px;

  box-shadow: 0 10px 30px
    rgba(0, 0, 0, 0.15);
}

.formas {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 30px;

  margin: 40px 0;
}

.forma {
  width: 120px;
  height: 120px;

  border: 4px solid #222;
  cursor: pointer;

  transition:
    transform 0.2s,
    opacity 0.2s;
}

.forma:hover {
  transform: scale(1.08);
}

.forma:active {
  transform: scale(0.95);
}

.circulo {
  border-radius: 50%;
  background: #ef4444;
}

.quadrado {
  background: #3b82f6;
}

.triangulo {
  width: 0;
  height: 0;

  padding: 0;

  border-top: 0;
  border-right: 60px solid transparent;
  border-bottom: 110px solid #22c55e;
  border-left: 60px solid transparent;

  background: transparent;
}

#mensagem {
  min-height: 35px;

  font-size: 24px;
  font-weight: bold;
}

@media (max-width: 500px) {
  .jogo {
    padding: 20px;
  }

  .forma {
    width: 90px;
    height: 90px;
  }

  .triangulo {
    width: 0;
    height: 0;

    border-right-width: 45px;
    border-bottom-width: 85px;
    border-left-width: 45px;
  }
}