* {
    margin: 0;
    padding: 0;
    font-family: sans-serif;
    box-sizing: border-box;
}


body {
    background-image: url(../img/bgadmon.jpg);
    background-position: center center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-size: cover;
    display: flex;
    min-height: 100vh;
}

form {
    margin: auto;
    width: 50%;
    max-width: 500px;
    background: 30px;
    border: 1px solid rgba(0,0,0,0,2)
}

h2 {
    text-align: center;
    margin-bottom: 20px;
    color: rgba(0,0,0,0.5);
}

input {
    display: block;
    padding: 10px;
    width: 100%;
    margin: 30px 0;
    font-size: 20px;
}

@media (max-width:768px) {
    form {
        width: 75%;
    }
}

@media (max-width:480px) {
    form {
        width: 95%;
    }
}