body {
  text-align: center;
}

#connect4 {
  background-color: yellow;
  display: inline-block;
}

.col {
  width: 75px;
  height: 75px;
  display: inline-block;
  background-color: white;
  border-radius: 50%;
  margin: 17px;
}

.col.empty {
  cursor: pointer;
}

.next-red {
  background-color: rgba(255, 0, 0, 0.2);
}

.next-black {
  background-color: rgba(0, 0, 0, 0.2);
}

.col.red {
  background-color: red;
}

.col.black {
  background-color: black;
}
#leftdivider {
  background: grey;
  top:20%;
  position: absolute;
  float:left;
  height: 80%;
  width: 10%;
  border: solid 1px black;
            }
#rightdivider {
  background: grey;
  top:20%;
  position: absolute;
  right:0;
  height: 80%;
  width: 10%;
  border: solid 1px black;
                }