.grid-container {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  grid-template-areas:  "big  big  big  .     .     ."
                        "big  big  big  large large large"
                        "last last last last  last  last";
  grid-gap: 1rem;
}

article:first-of-type {
  grid-area: big;
}

article:nth-of-type(5) {
  grid-area: large;
}

article:last-of-type {
  grid-area: last;
}


/* footer en bas d'article */
article {
  display: grid;
  grid-template-rows: auto 1fr auto;
}

/* variante

article {
display: flex;
flex-direction: column;
}
footer {
margin-top: auto;
}
*/



/* Reset */

html {
  font-size: 62.5%;
  box-sizing: border-box;
}

* {
  box-sizing: inherit;
}

body {
  margin: 1rem;
  background: #fff;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 1.8rem;
  line-height: 1.5;
}

h1, h2 {
  font-weight: normal;
}

section {
  margin-bottom: 1em;
}

article {
  padding: 1rem;
  color: #fff;
}


article:nth-of-type(1) {
  background: orange;
}
article:nth-of-type(2) {
  background: hotpink;
}
article:nth-of-type(3) {
  background: olivedrab;
}
article:nth-of-type(4) {
  background: dodgerblue;
}
article:nth-of-type(5) {
  background: slategray;
}
article:nth-of-type(6) {
  background: tan;
}

.read-more {
  padding: 1rem;
  text-decoration: none;
  color: #fff;
  background: rgba(0,0,0,0.2);
}