Solucionando o desafio

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

.corpo {
  background-color: #444444;
  padding: 8px;
  width: 100vw;
  height: 100vh;

  display: grid;
  grid-template-columns: 1fr 1fr 1fr 1fr;
  grid-template-rows: 1fr 1fr 1fr 1fr;
}

.cabecalho {
  background-color: #cc2a2a;
  border-radius: 10px;
  min-width: 50px;
  min-height: 50px;
  margin: 8px;

  grid-column: span 4;
}

.lateral {
  background-color: #45cc2a;
  border-radius: 10px;
  min-width: 50px;
  min-height: 50px;
  margin: 8px;

  grid-column: span 1;
  grid-row: span 3;
}

.meio {
  background-color: #2aa6cc;
  border-radius: 10px;
  min-width: 50px;
  min-height: 50px;
  margin: 8px;

  grid-column: span 2;
  grid-row: span 3;
}

.direita-cima {
  background-color: #352acc;
  border-radius: 10px;
  min-width: 50px;
  min-height: 50px;
  margin: 8px;

  grid-column: span 1;
  grid-row: span 1;
}

.direita-baixo {
  background-color: #cc2a96;
  border-radius: 10px;
  min-width: 50px;
  min-height: 50px;
  margin: 8px;

  grid-column: span 1;
  grid-row: span 2;
}