style.css

body{
  font-size: 13px;
  line-height: 1.45555;
  font-family: Arial, Sans;
}

h1 {
  font-size: 21px;
  margin-left: 0px;
}
#container { width: 400px; }
ul { padding: 0;  margin: 0;}
li {
    padding: 0;
    float: left;
    margin: 10px;
    list-style: none;
    outline: solid;
    width: 80px;
    height: 80px;
    position: relative;
    text-align: center;
    padding-top: 30px;
    box-sizing: border-box;
}

li .layer{
  position: absolute;
  height: 100%;
  width: 100%;
  background: #1abc9c;
  left: 0;
  top: 0;
}

li .layer.flipped{
  background: transparent;
}

li .layer.flipped.matched {
    background: #bdc3c7;
    z-index: -1;
}

.gridGen{
  width: 400px;
}

.cell{
    width: 78px;
    margin: 10px;
    border: 1px solid #080404;
    height: 80px;
    display: inline-block;
}