.box-container {
    position: relative;
    overflow: hidden; /* 🔑 keep snow inside box */
    border-radius: 5px;
    height: 100%;
}

/* Snow layer */
.snow {
    position: absolute;
    top: -100%;
    left: 0;
    width: 100%;
    height: 200%;
    background-image:
        radial-gradient(2px 2px at 20px 30px, white, transparent),
        radial-gradient(2px 2px at 80px 90px, white, transparent),
        radial-gradient(1px 1px at 150px 50px, white, transparent),
        radial-gradient(2px 2px at 220px 120px, white, transparent),
        radial-gradient(1px 1px at 260px 80px, white, transparent);
    background-size: 300px 200px;
    animation: snowFall 6s linear infinite;
    opacity: 0.8;
}

/* Animation */
@keyframes snowFall {
    0% {
        transform: translateY(0);
    }
    100% {
        transform: translateY(50%);
    }
}