.btn-login-mb,
.btn-reg-mb {
    display: none;
}

.btn-login,
.btn-reg {
    display: inline-block;
    padding: 10px 20px;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    margin: 0.5rem;
    width: auto;
}

.btn-login {
    background-color: #b20000;
}

.btn-reg {
    background-color: #7a9c59;
}

.btn-login:hover {
    background-color: #920e0e;
}

.btn-login:active {
    background-color: #b20000;
}

.btn-reg:hover {
    background-color: #45a049;
}

.btn-reg:active {
    background-color: #3e8e41;
}

@media (max-width: 645px) {

    .btn-reg,
    .btn-login {
        display: none;
    }

    .btn-login-mb,
    .btn-reg-mb {
        display: inline-block;
        padding: 10px 20px;
        color: white;
        text-decoration: none;
        border-radius: 4px;
        text-align: center;
        margin: 1.5rem auto;
        width: calc(50% - 1rem);
    }

    .btn-login-mb {
        background-color: #b20000;
    }

    .btn-reg-mb {
        background-color: #7a9c59;
    }

    .btn-login-mb {
        margin-left: .75rem;
    }

    .btn-login-mb:hover {
        background-color: #920e0e;
    }

    .btn-login-mb:active {
        background-color: #b20000;
    }

    .btn-reg-mb:hover {
        background-color: #45a049;
    }

    .btn-reg-mb:active {
        background-color: #3e8e41;
    }
}