styles.css

 p, ul{
	margin: 0;
	padding: 0;
}

.dropbtn {
  background-color: #3498DB;
  color: white;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
	margin-left: 17rem;
}

.dropbtn:hover, .dropbtn:focus {
  background-color: #2980B9;
}

.dropdown-content {
  display: none;
  position: absolute;
	margin-left: 2rem;
}

.show {display: block;}

.group{
  background: #660000;
	color: white;
	padding: .5em .5em 1em;
	max-width: 22em;
  height: 13rem;
	margin: .5em auto;
	-webkit-border-radius: 5px;
	border-radius: 5px;
}

.left {
  float: left;
}
.right {
  float: right;
}
.pointer {
  cursor: pointer;
}
.center {
	text-align: center;
}
.monthname{
  width: 16.5em;
  font-size: 20px;
}

ul{
  list-style-type: none;
}

li{
	width: -webkit-calc(100%/7);
	float: left;
	text-align: center;
  height: 20px;
	padding: .25em 0;
	cursor: pointer;
}

li:hover{
	color: #3366ff;
}

.start, .end{
	margin: 2rem;
}