body{
    margin:0;
    padding:0;
    font-family:montserrat;
    background:linear-gradient(120deg,#2980b9,#8e44ad);
    height: 100vh;
    overflow:hidden;
}
.center{
    position:absolute;
    top:50%;
    left:50%;
    transform:translate(-50%,-50%);
    width:400px;
    background:white;
    border-radius:10px;
}
.center h1{
    text-align:center;
    padding:0 0 20px 0;
    boder-bottom:1px solid silver;
}
.center form{
    padding:0 40px;
    box-sizing:border-box;
}
form.txt_field{
    position:relative;
    boder-bottom:2px solid #adadad;
    margin:30px 0;
}
.txt_field input{
    width.100%;
    padding:0 5px;
    height:40px;
    font-size:16px;
    border:none;
    background:none;
    outline:none;
}
.txt_field label{
    position:absolute;
    top:50%;
    left:5px;
    color:#adadad;
    transform:translateY(-50%);
    font-size:16px;
    pointer-events:none;
    transition:.5s;
}
.txt_field span::before{
    content:'';
    position:absolute;
    top:40px;
    left:0;
    width:0%;
    height:2px;
    background: #2691d9;
    transition: .5s;
}
.txt_field input:focus ~ label,
.txt_field input:valid ~ label{
    top: -5px;
    color: #2691d9;
}
.txt_field input:focus ~ span::before,
.txt_field input:valid ~ span::before{
    width:100%;
}
.pass{
    margin: -5px 0 20pc 5px;
    color:#a6a6a6;
    cursor:pointer;
}
.pass:hover{
    text-decoration:underline;
}
input[type="submit"]{
    width: 100%;
    height:50px;
    border:1px solid;
    background: #2691d9;
    border-radius: 25px;
    font-size:18px;
    color:#e9f4fb;
    font-weight: 700;
    cursor:pointer;
    outline:none;
}
input[type="submit"]:hover{
    border-color:#2691d9;
    transition: ,5s;
}
.signup_link{
    margin:30px 0;
    text-align:center;
    font-size:16px;
    color:#666666;
}
.signup_link a{
    color:#2691d9;
    text-decoration:none;
}
.signup_link a:hover{
    text-decoration: underline;
}