body{
  height: 100%
  margin: 0;
  padding: 0;
  text-align: center;
}
#wrap {
  width: 640px;
  margin: 0 auto;
}
.control_time {
  margin-left:80px;
  margin-top: 60px;
  width: 200px;
  font-size: 2em;
  float: left;
}
.button {
  width: 60px;
  height: 80px;
  margin-top: 20px;
  margin-right: 5px;
  border-radius: 3px;
  background: #fafafa;
  border: solid 1px #78b7bb;
  font-size: 1.5em;
  cursor: pointer;
}
.clock_time {
  font-size: 12em;
}
.clock_reset {
  display: none;
}
.btn-control {
  margin-top: 50px;
  margin-right: 40px;
  padding: 15px 8px;
  border-radius: 5px;
  border: solid 1px #78b7bb;
  font-size: 1.5em;
  cursor: pointer;
}
@media screen and (max-width: 720px) {
#wrap {
  max-width: 100%;
  width: 320px;
}
.control_time {
  margin-left: 40px;
  margin-top: 60px;
  width: 100px;
  font-size: 1em;
  float: left;
}
.button {
  width: 30px;
  height: 30px;
  margin-top: 20px;
  margin-right: 5px;
  border-radius: 3px;
  font-size: 1em;
}
.clock_time {
  font-size: 6em;
}
.btn-control {
  margin-top: 50px;
  margin-right: 10px;
  padding: 15px 8px;
  font-size: 1em;
	}
}