body
  display flex
  
nav
  width 250px
  overflow-y auto
  position fixed
  top 0
  background #ddd
  bottom 0

  h2
    margin-left 7px
  
  ul
    list-style none
    margin 0
    padding 0.5em
  
  li
    padding 0
    padding-top 10px
    margin 0
    margin-bottom 5px
    border-top 1px solid rgb(190,190,190)
  
  li:first-child
    border 0
  
  li li
    padding-top 5px
    margin 0
    border 0

  li li a
    display block
    color #444
    padding 0.25em 0.5em
    text-decoration none

    &:hover
      background #ccc

    &.active
      background #444
      color #eee

iframe
  margin-left 250px
  border 0
  flex 1