body{
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100vh;
} 
  
.loader{
    height: 10px ;
    background-color: #000 ;
    position: absolute;
    transition: opacity 0.3s ease-in-out;
}
.content{
    height: 100vh;
    width: 100%;
    background: #fff;
    display: none;
}