/* Drag-over highlight */
#drop-zone.drag-over {
    border-color: #3b82f6;
    background-color: #eff6ff;
}

/* Truncate long cells without breaking layout */
.cell-truncate {
    max-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Smooth modal backdrop */
.modal-backdrop {
    animation: fadeIn 0.15s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
    .modal-backdrop { animation: none; }
}

/* Visible focus ring for keyboard navigation */
:focus-visible {
    outline: 3px solid #2563eb;
    outline-offset: 2px;
}

/* Screen-reader only utility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    white-space: nowrap;
    border: 0;
}