.sign-box {
    max-width: 400px;
}

.sign-box .sign-avatar {
    width: auto;
    margin-bottom: 20px;
}

.sign-box .sign-avatar img {
    display: block;
    width: auto;
    -webkit-border-radius: 0%;
    border-radius: 0%;
    margin: 0 auto;
}

.sign-box .btn {
    margin: 30px auto 12px;
}