body {
  background-color: blanchedalmond;
}

body * {
  margin: 10px;
}

body > * {
  width: 98vw;
}

header, footer {
  height: 10vh;
  background-color: dodgerblue;
}

main {
  display: flex;
  min-height: 80vh;
  margin: 0;
}

aside {
  background-color: dodgerblue;
  flex-grow: 1;
}

article {
  background-color: dodgerblue;
  flex-grow: 4;
}