.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  width: 400px;
  height: 400px;
  border: 8px solid white;
  box-sizing: border-box;
}

.cell {
  position: relative;
}

.red {
  background-color: #d33220; /* 深红 */
}

.blue {
  background-color: #1d297e; /* 深蓝 */
}

.bar {
  position: absolute;
  height: 20px;
  width: 60px;
}

.top-bar {
  top: 0;
  left: 50%;
  transform: translateX(-50%);
}

.bottom-bar {
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
}