pr1

*{
    margin: 0;
    padding: 0;
    text-decoration: none;
    font-family: "montserrat";
}
body{
    background: #333;
}
.card-middle{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}
.card-middle{
    cursor: pointer;
    width: 340px;
    height: 480px;
}
.front,.back{
    width: 100%;
    height: 100%;
    overflow: hidden;
    backface-visibility: hidden;
    position: absolute;
    transition: transform .6s linear;
}
.front img{
    height: 100%;
}
.back{
    background: #f1f1f1;
    transform: perspective(600px) rotateY(180deg);
}
.back-content{
    color: #2c3e50;
    text-align: center;
    width: 100%;
}
.back-content h2{
    margin-top: 30px;
}
.front{
    transform: perspective(600px) rotateY(0deg);
}
.form{
    margin-top: 20px;
}
input[type = "text"], input[type = "password"]{
    display: block;
    margin-top: 20px;
    border: 0;
    background: none;
    border: 1.5px solid #333;
    text-align: center;
    margin: 20px auto;
    padding: 7px 10px;
    border-radius: 8px;
}
input[type = "submit"]{
    display: block;
    margin-top: 20px;
    border: 0;
    background: none;
    border: 1.5px solid #333;
    text-align: center;
    margin: 20px auto;
    padding: 7px 25px;
    border-radius: 8px;
    cursor: pointer;
}
.extra{
    margin-top: 37px;
}
.extra p a{
    color: #333;
}
.sm a{
    color: #333;
    display: inline-flex;
    margin-top: 30px;
    font-size: 23px;
    width: 40px;
    height: 40px;
    justify-content: center;
    align-items: center;
    transition: 0.3s;
}
.sm a:hover{
    background-color: #333;
    color: #f1f1f1;
    border-radius: 20px;
}
.card-middle:hover > .front{
    transform: perspective(600px) rotateY(-180deg);
}
.card-middle:hover > .back{
    transform: perspective(600px) rotateY(0deg);
}