.split-flap-tile {
    display: inline-block;
    min-width: 1ch;
    padding: 0.05em 0.05em;
    margin: 0 1px;
    background: var(--card);
    color: var(--foreground);
    border-radius: 4px;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
    font-weight: 700;
    box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.4), 0 1px 0 rgba(255, 255, 255, 0.05);
    animation: split-flap-flip 480ms ease-out;
    transform-origin: 50% 100%;
}

@keyframes split-flap-flip {
    0%   { transform: rotateX(-90deg); opacity: 0; }
    50%  { transform: rotateX(0deg);   opacity: 1; }
    100% { transform: rotateX(0deg);   opacity: 1; }
}