body.login #install-button {
    margin-top: 0.25em;
    font-size: 0.7em;
    color: white !important;
    border-color: white !important;
    background: #fff1 !important;
    animation: slideInDown;
    top: 0.15em;
    animation-duration: 1s;
    animation-fill-mode: backwards;
    animation-delay: 1s;
}

body.login #install-button::before {
   color:white;
   font-weight: bold;
}