.grid-container {
  border: 2px solid #007bff;
  padding: 15px;
  margin: 10px 0;
}

.grid-fallback {
  background: #ffebee;
  color: #c62828;
}

.grid-fallback .item {
  display: inline-block;
  width: 30%;
  margin: 1%;
  padding: 10px;
  background: #fff;
  border: 1px solid #ddd;
  text-align: center;
}

@supports (display: grid) {
  .grid-container {
    background: #e8f5e8;
    color: #2e7d32;
  }
  
  .grid-container .grid-items {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
  }
  
  .grid-container .item {
    width: auto;
    margin: 0;
    padding: 15px;
    background: #fff;
    border: 1px solid #4caf50;
    text-align: center;
  }
}