body {
  line-height:1.6;
  font-size:18px;
  color:#444;
  padding:0 10px;
}
h1,h2,h3 {
  line-height:1.2;
}
ul.flex-2-cols {
  display: flex;
  flex-wrap: wrap;
  list-style-type: none;
}
ul.flex-2-cols li {
  width: 50%;
  box-sizing: border-box;
}
ul.flex-3-cols {
  display: flex;
  flex-wrap: wrap;
  list-style-type: none;
}
ul.flex-3-cols li {
  width: 33%;
  box-sizing: border-box;
}
ul li .container {
  position: relative;
  margin: auto;
  height: 40vh;
  padding: 20px;
}