html,body{
  margin: 0;
  padding: 0;

}

#app {
  box-sizing: border-box;
  max-width: 1920px;
  height: 100vh;
  margin: 0 auto;
  padding: 1rem;

  font-weight: normal;

  display: flex;
  flex-flow: column-reverse;
}

#header{
  flex: 0 0 5rem;
}

#main-content{
  flex: 1 1 auto;

}