style.css

html, body{
  height:100%;
}
body{
  background-repeat: no-repeat;
  background-size: cover;
  background-position: 50% 50%;
  margin:0;
  font-family: 'Trebuchet MS';
}
.overlay{
  width:100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.2);
  display: flex;
  justify-content: center;
  align-items: center;
  color:#fff;
  flex-direction: column;
}

.top{
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  font-size:25px;
  display: flex;
  padding:20px;
  color:rgba(255,255,255,0.5);

}
.top .left{
  flex: 1 0 auto;
  text-align: left;
}
.top .right{
  flex: 1 1 auto;
  text-align: right;
}
.time{
  font-size:200px;
  margin:0;
  font-weight: 400;
}
.greeting{
  font-size:80px;
  font-weight: 400;
  margin:0;
}
input.user-name, input.interest{
  width:20em;
  text-align: center;
  background: 0;
  border: 0;
  border-bottom: 2px solid #fff;
  outline: 0;
  font-size:30px;
  color: #fff;
  margin-top: 20px;
  display:none;
}
a.photoby{
  color: rgba(255,255,255,0.5);
  text-decoration: none;
}
.change-btn{
  position: absolute;
  bottom: 20px;
  font-size: 20px;
  cursor:pointer;
  display: none;
}
.change-btn:hover{
  transition: all 0.5s ease-out;
  text-decoration: underline;
}