body.app {
    /* Minimalist Modern Gradient - Soft Slate & Airy Blue */
    background: linear-gradient(135deg, #fdfbfb 0%, #ebedee 100%);
    background-size: 200% 200%;
    animation: gradient 20s ease infinite;
    height: 100vh;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* Subtle, slow moving gradient */
@keyframes gradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* Ensure card stands out slightly more against light background if needed, 
   though the default coreui card usually has a white background/border. 
   Adding a subtle shadow for a 'floating' feel. */
.card {
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    border: none;
}