body
{
     background-color: #111827;
}

.login-card
{
   background-color: #1a1f2b;
   box-shadow: 0px 0px 20px rgb(76, 0, 255); 
   animation-name: card;
   animation-duration: 1s;
   animation-iteration-count: infinite;
   animation-direction: alternate;
}

@keyframes card
{
    0%{box-shadow: 0px 0px 2px rgb(76, 0, 255)}
    10%{box-shadow: 0px 0px 5px rgb(76, 0, 255)}
    20%{box-shadow: 0px 0px 8px rgb(76, 0, 255)}
    30%{box-shadow: 0px 0px 11px rgb(76, 0, 255)}
    35%{box-shadow: 0px 0px 14px rgb(76, 0, 255)}
    40%{box-shadow: 0px 0px 17px rgb(76, 0, 255)}
    50%{box-shadow: 0px 0px 20px rgb(76, 0, 255)}
    60%{box-shadow: 0px 0px 23px rgb(76, 0, 255)}
    70%{box-shadow: 0px 0px 26px rgb(76, 0, 255)}
    80%{box-shadow: 0px 0px 29px rgb(76, 0, 255)}
    90%{box-shadow: 0px 0px 32px rgb(76, 0, 255)}
    100%{box-shadow: 0px 0px 35px rgb(76, 0, 255)}
}