.container {
    display: flex;
    overflow-x: scroll;
    scroll-snap-type: x mandatory;
    background-color: aqua;
}

.item {
    scroll-snap-align: start;
    flex: 0 0 100%;
}
.container {
    scroll-snap-type: y proximity;
    height: 200vh;
    overflow-y: scroll;
    scroll-behavior: smooth;
}