/* Flowing background — the storefront's red/gold/silver glow over the shared canvas */
        .bg-grid {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background:
                radial-gradient(ellipse at 12% 18%, rgba(230, 57, 70, 0.15) 0%, transparent 42%),
                radial-gradient(ellipse at 88% 82%, rgba(212, 175, 55, 0.12) 0%, transparent 42%),
                radial-gradient(ellipse at 50% 50%, rgba(192, 192, 192, 0.05) 0%, transparent 60%);
            z-index: 0;
            animation: bgFlow 20s ease-in-out infinite alternate;
        }

        @keyframes bgFlow {
            0% {
                background-position: 0% 0%, 100% 100%, 50% 50%;
            }
            100% {
                background-position: 10% 10%, 90% 90%, 60% 40%;
            }
        }

        .gradient-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background:
                linear-gradient(135deg, rgba(230, 57, 70, 0.03) 0%, transparent 30%, rgba(212, 175, 55, 0.03) 70%, transparent 100%),
                repeating-linear-gradient(90deg, transparent, transparent 2px, rgba(192, 192, 192, 0.015) 2px, rgba(192, 192, 192, 0.015) 4px);
            z-index: 1;
            pointer-events: none;
            animation: gradientShift 15s ease-in-out infinite;
        }

        @keyframes gradientShift {
            0%, 100% { opacity: 0.6; }
            50% { opacity: 0.9; }
        }