/* Reserve each position's space so the page doesn't jump when an ad arrives. */
.ad-slot {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 16px auto;
}

.ad-topleaderboard,
.ad-bottomleaderboard {
    min-height: 90px;   /* 728x90 */
}

.ad-sidebar {
    min-height: 250px;  /* 300x250 */
    position: sticky;
    top: 16px;
}

/* Phones: keep in sync with PHONE_QUERY in js/adWaterfall.js */
@media (max-width: 767px) {
    .ad-topleaderboard,
    .ad-bottomleaderboard {
        min-height: 50px;   /* 320x50 */
    }
}