*{
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
}

.main{
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}
.main>.img1{
    width: 81vw;
 
  }
  .img1>img{
    max-width: 100%;
  }

  @media(max-width:750px){
 
    .main{
      width: 100%;
      height: 100%;
      height: 100vh;
    
    }
    .main>.img1{
        width: 100vw;
     
      }
   }