*{
    margin: 0;
    padding: 0;
}

.form{
    width: 400px;
    height: 500px;   
    padding:0 30px 0px 20px;
    margin: auto;
}
.form h1{
font-size: 3.5rem;
text-align: center;
margin: 20px 0;
}
.form h1:after{
    content: '';
    display: block;
    width: 340px;
    height: 1px;
    margin: 4px 0 0 5px;
    background-color: #38363648;
}
@media (max-width:780px){
    .form{
        width: 340px;
        height: 500px;   
    
        margin: auto;
    }
    .form h1:after{
        content: '';
        display: block;
        width: 280px;
        height: 1px;
        margin: 4px 0 0 5px;
        background-color: #38363648;
    }
}