.grid-container {
  display: grid;
  grid-template-columns: repeat(3, 1fr); /* 3 colonnes égales */
  grid-template-rows: repeat(2, 150px);  /* 2 lignes de 150px */
  gap: 10px; /* espace entre les cases */
  max-width: 600px;
  margin: 0 auto;
}

.item {
  background-color: #4CAF50;  
  color: white;
  font-size: 2em;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 8px;
}
