body {
  /*  background: url('https://picsum.photos/1920/1080?blur=3') no-repeat center center fixed;
  */  background-size: cover;
    position: relative;
}

    body::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.5); /* dark overlay */
        z-index: 0;
    }

.login-card {
    position: relative;
    z-index: 1;
    background: #fff;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0px 8px 24px rgba(0,0,0,0.3);
    width: 350px;
}