.invisible-grid > .empty-cell {
    background: transparent;
    border: 1px solid transparent;
}

.visible-grid > .empty-cell {
    background: transparent;
    border: 1px inset rgba(128, 128, 128, 0.3);
}

.mino, .I-mino, .J-mino, .L-mino, .O-mino, .S-mino, .T-mino, .Z-mino {
    background: rgba(127, 229, 255, 0.3);
    border: 1px solid rgba(127, 229, 255, 0.7);
    border-radius: 0.3vmin;
}

.locked-mino {
    background: rgba(242, 255, 255, 0.5);
    border-color: rgba(242, 255, 255, 0.7);
}

.cleared-line {
    background: white;
}

.trail {
    background: rgba(255, 255, 255, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 0.3vmin;
}

.ghost {
    background: rgba(255, 255, 255, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.4);
    border-radius: 0.3vmin;
}