Preview:
body{
    width: 100%;
    height: 100vh;
    margin:0px;
    padding:0px;
    overflow-x: hidden;
    background:url("https://images.unsplash.com/photo-1530893609608-32a9af3aa95c?ixid=MXwxMjA3fDB8MHxzZWFyY2h8MTJ8fHRlY2h8ZW58MHx8MHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=500&q=60") !important;
    background-size:cover !important;
    background-repeat: no-repeat !important;
    background-position: center !important;
}
*{
    list-style: none;
    box-sizing: border-box;
}

.container{
    display:flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    width:100%;
    height:100vh;
}
.container .form-cont{
    width:450px;
    padding:12px;
    background:rgba(0,0,0,.8);
    color:#fff;
}

.container .form-cont form textarea{
    height:100px;
}
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