如何使用flexbox填充剩余高度？

html,
body {
  height: 100%;
}
.site-main {
  height: calc(100% - 72px);
  display: flex;
}
.site-main > div {
  min-width: 85%;
  height: 100%;
}
.site-main > aside {
  min-width: 15%;
  height: 100%;
  background-color: $darkest-blue-grey;
}html,
body {
  height: 100%;
}
.sit