.main-panel {
    height: 100%;
}

.main-panel .row {
    height: 100%;
}

.login-panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-width: 300px;
    height: 400px;
    box-shadow: 0 0 20px #b3b3b3;
    padding: 20px 10px;
}

.login-panel .login-user-avatar {
    min-width: 150px;
    min-height: 150px;
    background-image: url(/user-icon.jpg);
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
    border-radius: 50%;
    margin: 20px 0;
    -webkit-filter: grayscale(100%);
    filter: gray;
    transform: rotateY(0deg);
    backface-visibility: hidden;
    transition: transform .4s ease;
}

.login-panel .login-form input {
    border: 0;
    border-bottom: 1px solid gray;
    border-radius: 0;
}

.login-panel .login-form input:focus, .login-panel .login-form input:active, .login-panel .login-form input:hover {
    outline: none;
    box-shadow: none;
}

.login-panel .login-form .btn.btn-primary {
    margin-top: 40px;
    text-transform: uppercase;
    border-radius: 0;
}

.login-panel .login-response {
    max-height: 0;
    width: 100%;
    transition: max-height .4s ease;
}

.login-panel .login-response.has-error {
    max-height: 100px;
}