*{
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

.viewport{
  min-height: 100vh;
  min-width: 100%;
  border: 5px solid black;
}

.flex-parent{
  display: flex;
}

.flex-col{
  flex-direction: column;
}

.space-around{
  justify-content: space-around;
}

.space-evenly{
  justify-content: space-evenly;
}

.align-center{
  align-items: center;
}

.nav{
  min-width: 100%;
  /* min-height: 20vh; */
  border: 5px dashed blue;
}


.box-1{
  min-width: 20vw;
  background-color: yellow;
}

.box-2{
  min-width: 20vw;
  background-color: purple;
}

.box-3{
  min-width: 20vw;
  background-color: red;
}

.content{
  min-width: 100%;
  min-height: 80vh;
  border: 5px dashed orange;
}

.footer{
  min-width: 100%;
  /* min-height: 20vh; */
  border: 5px dashed cyan;
  position: fixed;
  bottom: 0px;
  left: 0px;
}

.sidebar-left{
  min-width: 20%;
  background: teal;
}

.main-area{
  min-width: 60%;
  background: green;
}

.sidebar-right{
  min-width: 20%;
  background: blue;
}

.box-4{
  min-width: 15%;
  background: pink;
}

.box-5{
  min-width: 30%;
  background: maroon;
}

.box-6{
  min-width: 20%;
  background: black;
}

.navigation {
  display: flex;
  flex-flow: row wrap;
  justify-content: flex-end;

  list-style: none;
  margin: 0;
  background: deepskyblue;
}

.navigation a {
  text-decoration: none;
  display: block;
  padding: 1em;
  color: white;
}

.navigation a:hover {
  background: #1565C0;
}

@media all and (max-width: 800px) {
  .navigation {
    justify-content: space-around;
  }
}

@media all and (max-width: 600px) {
  .navigation {
    flex-flow: column wrap;
    padding: 0;
  }
  .navigation a {
    text-align: center;
    padding: 10px;
    border-top: 1px solid rgba(255, 255, 255,0.3);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  }
  .navigation li:last-of-type a {
    border-bottom: none;
  }
}