/* Generic loading shapes contain no stored book records. */
.shelf-placeholder { height: var(--book-height); width: calc(var(--book-height) * .625); background: color-mix(in srgb, var(--shelf-label) 12%, transparent); }
.book.is-loading { cursor: progress; pointer-events: none; }
.book.is-loading .book__cover, .book.is-loading .book__spine-label { visibility: hidden; }
.book.is-loading .book__front { background: color-mix(in srgb, var(--shelf-label) 16%, var(--bookcase-surface)); }
.book__back-cover { display: block; width: 100%; height: 100%; object-fit: contain; }
.collection-status { color: var(--muted-text); font-size: .9rem; }
.collection-status button { border: 0; padding: 6px; color: inherit; background: transparent; text-decoration: underline; cursor: pointer; }