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

body{
    height: 100%;
}

img {
    position: absolute;
    background-size: cover;
    background-attachment: fixed;
    background-position: center 0px;
    background-repeat: no-repeat;
    width: 100%;
    height: 810px;
    top: -91px;
}
.back .curve {
    position: absolute;
    width: 20px;
    height: 20px;
    left: 72px;
    top: 52px;
    background: #D9D9D9;
    border-radius: 50px;
}

.curve:hover{
    background: transparent;
    border: 2px solid #D9D9D9;
    cursor: pointer;
}