.u-stack,
.u-stack-sm,
.u-stack-md,
.u-stack-lg {
    --u-stack-gap: var(--stack-gap-sm);
    display: flex;
    flex-direction: column;
    gap: var(--u-stack-gap);
}

.u-stack-sm {
    --u-stack-gap: var(--stack-gap-sm);
}

.u-stack-md {
    --u-stack-gap: var(--stack-gap-md);
}

.u-stack-lg {
    --u-stack-gap: var(--stack-gap-lg);
}