/* Keep · 书架与新书上架。沿用主界面的纸色、赤陶与衬线，不做后台面板。 */
.dr-books {
  display: flex; align-items: center; justify-content: space-between;
  background: var(--bg); border-radius: 16px; padding: 13px 14px;
  cursor: pointer; font-size: 14.5px; font-family: var(--round);
  letter-spacing: .04em; box-shadow: var(--bubble-shadow);
}
.dr-books:active { background: var(--border); }
#booksCount { color: var(--muted); font-size: 12px; letter-spacing: 0; }

#booksView {
  position: fixed; inset: 0; z-index: 70; background: var(--bg);
  display: none; flex-direction: column;
}
#booksView.open { display: flex; }
#booksHead {
  flex: 0 0 auto; display: flex; align-items: center; gap: 12px;
  min-height: 52px; padding: calc(env(safe-area-inset-top) + 12px) 16px 8px;
  background: var(--bg);
}
#booksBack {
  width: 30px; height: 30px; border-radius: 50%; flex: 0 0 auto;
  border: 1px solid var(--border); background: var(--bg); color: var(--muted);
  font-size: 17px; line-height: 1; cursor: pointer; padding: 0;
}
#booksTitle {
  min-width: 0; color: var(--muted); font-size: 14px;
  font-family: var(--round); white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
#booksAdd {
  width: 34px; height: 34px; margin-left: auto; padding: 0;
  border: none; border-radius: 50%; background: transparent; color: var(--text);
  font: 300 27px/32px -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  cursor: pointer;
}
#booksAdd:active { background: var(--user-bubble); transform: scale(.94); }
#booksAdd.hidden { visibility: hidden; pointer-events: none; }
#booksBody {
  flex: 1 1 auto; min-height: 0; overflow-y: auto;
  padding: 12px 16px calc(env(safe-area-inset-bottom) + 28px);
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin; scrollbar-color: rgba(217,119,87,.4) transparent;
}

.bk-intro { margin: 8px 2px 22px; }
.bk-intro h1 { margin: 0 0 5px; font-size: 29px; line-height: 1.2; font-weight: 600; }
.bk-intro p { margin: 0; color: var(--muted); font-size: 13.5px; font-family: var(--round); }
.bk-filters {
  display: flex; gap: 7px; margin: 0 -16px 20px; padding: 0 16px 2px;
  overflow-x: auto; scrollbar-width: none;
}
.bk-filters::-webkit-scrollbar { display: none; }
.bk-filter {
  flex: 0 0 auto; border: 1px solid var(--border); border-radius: 999px;
  background: transparent; color: var(--muted); padding: 6px 12px;
  font: 12.5px/1 var(--round); cursor: pointer;
}
.bk-filter.on { border-color: var(--text); color: var(--text); background: var(--user-bubble); }
.bk-section { margin: 0 0 25px; }
.bk-section-title {
  margin: 0 2px 10px; color: var(--muted); font: 12px/1.4 var(--round);
  letter-spacing: .08em;
}
.bk-list { display: grid; gap: 10px; }
.bk-card {
  display: grid; grid-template-columns: 52px minmax(0,1fr); gap: 13px;
  align-items: center; padding: 12px; border-radius: 17px;
  background: var(--panel); box-shadow: var(--bubble-shadow);
}
.bk-spine {
  width: 52px; height: 70px; border-radius: 5px 10px 10px 5px;
  display: flex; align-items: center; justify-content: center; overflow: hidden;
  color: #fff; background: #B97962; box-shadow: inset 4px 0 rgba(48,45,39,.12);
  font-size: 18px; font-weight: 600;
}
.bk-spine:nth-child(3n+1) { background: #8C8374; }
.bk-title { font-size: 16px; line-height: 1.35; font-weight: 600; overflow-wrap: anywhere; }
.bk-author { margin-top: 4px; color: var(--muted); font-size: 12.5px; font-family: var(--round); }
.bk-meta { margin-top: 7px; display: flex; flex-wrap: wrap; gap: 5px; }
.bk-tag {
  color: var(--muted); background: var(--bg); border-radius: 999px;
  padding: 3px 8px; font: 11px/1.3 var(--round);
}
.bk-empty { color: var(--muted); text-align: center; margin-top: 34vh; transform: translateY(-50%); }
.bk-empty strong { display: block; color: var(--text); font-size: 19px; margin-bottom: 5px; }
.bk-empty span { font: 13px/1.6 var(--round); }

.bk-stage { width: min(100%, 680px); margin: 0 auto; }
.bk-stage-lead { margin: 7px 2px 18px; }
.bk-stage-lead h1 { margin: 0 0 6px; font-size: 25px; line-height: 1.3; font-weight: 600; }
.bk-stage-lead p { margin: 0; color: var(--muted); font: 13.5px/1.6 var(--round); }
.bk-drop {
  min-height: 170px; border: 1.5px dashed var(--border); border-radius: 20px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  padding: 24px 20px; text-align: center; cursor: pointer; background: var(--panel);
  transition: border-color .18s, background .18s;
}
.bk-drop.over { border-color: var(--accent); background: var(--user-bubble); }
.bk-drop-plus { color: var(--accent); font: 300 35px/1 -apple-system, sans-serif; }
.bk-drop-main { margin-top: 9px; font-size: 16px; }
.bk-drop-sub { margin-top: 5px; color: var(--muted); font: 12px/1.5 var(--round); }
.bk-picked { display: grid; gap: 8px; margin-top: 14px; }
.bk-file {
  display: flex; align-items: center; gap: 10px; min-width: 0;
  padding: 10px 12px; border-radius: 14px; background: var(--panel);
}
.bk-file-icon { color: var(--accent); font: 12px/1 var(--round); min-width: 36px; }
.bk-file-name { min-width: 0; flex: 1; font-size: 13.5px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.bk-file-size { color: var(--muted); font: 11px/1 var(--round); }
.bk-file-rm { border: none; background: transparent; color: var(--muted); font-size: 18px; cursor: pointer; padding: 2px 4px; }
.bk-actions { display: flex; gap: 9px; margin-top: 18px; }
.bk-btn {
  min-height: 44px; border-radius: 999px; padding: 10px 18px;
  border: 1px solid var(--border); background: transparent; color: var(--text);
  font: 14px/1.2 var(--round); cursor: pointer;
}
.bk-btn.primary { flex: 1; border-color: var(--accent); background: var(--accent); color: #fff; }
.bk-btn:disabled { opacity: .4; cursor: default; }
.bk-status { margin: 24vh auto 0; max-width: 320px; text-align: center; color: var(--muted); font: 14px/1.7 var(--round); }
.bk-spinner {
  width: 28px; height: 28px; margin: 0 auto 15px; border-radius: 50%;
  border: 2px solid var(--border); border-top-color: var(--accent);
  animation: bkspin .85s linear infinite;
}
@keyframes bkspin { to { transform: rotate(360deg); } }
.bk-error {
  margin-top: 16px; padding: 13px 15px; border-radius: 15px;
  color: #A54E38; background: rgba(201,100,66,.10); font: 13px/1.55 var(--round);
}

.bk-report-head { margin: 7px 2px 17px; }
.bk-report-head h1 { margin: 0 0 5px; font-size: 24px; font-weight: 600; }
.bk-report-head p { margin: 0; color: var(--muted); font: 13px/1.55 var(--round); }
.bk-version-list { display: grid; gap: 10px; }
.bk-version-wrap { display: grid; gap: 7px; }
.bk-version {
  position: relative; width: 100%; text-align: left; color: var(--text);
  border: 1px solid var(--border); border-radius: 18px; background: var(--panel);
  padding: 14px 42px 14px 15px; cursor: pointer; font-family: inherit;
}
.bk-version.selected { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent); }
.bk-version-failed { padding-right: 15px; cursor: default; border-style: dashed; }
.bk-version-failed .warn { color: #A54E38; }
.bk-check {
  position: absolute; right: 14px; top: 15px; width: 20px; height: 20px;
  border: 1.5px solid var(--border); border-radius: 6px;
}
.bk-version.selected .bk-check { border-color: var(--accent); background: var(--accent); }
.bk-version.selected .bk-check::after {
  content: "✓"; display: block; color: #fff; text-align: center;
  font: 600 13px/18px -apple-system, sans-serif;
}
.bk-version-title { font-size: 16px; font-weight: 600; line-height: 1.35; }
.bk-version-sub { margin-top: 3px; color: var(--muted); font: 12px/1.45 var(--round); overflow-wrap: anywhere; }
.bk-quality { margin-top: 9px; display: flex; flex-wrap: wrap; gap: 6px; }
.bk-quality span { padding: 3px 7px; border-radius: 999px; background: var(--bg); color: var(--muted); font: 11px/1.25 var(--round); }
.bk-quality .warn { color: #A54E38; background: rgba(201,100,66,.10); }
.bk-quality .hint { color: #9A6A3A; background: rgba(217,154,102,.14); }
.bk-recommend { color: var(--accent); }
.bk-compare {
  margin: 13px 0 0; padding: 12px 14px; border-left: 2px solid var(--border);
  color: var(--muted); font: 12.5px/1.65 var(--round);
}
.bk-samples { margin: 15px 0 0; }
.bk-samples details { border-top: 1px solid var(--border); padding: 10px 2px; }
.bk-samples summary { cursor: pointer; color: var(--muted); font: 12.5px/1.4 var(--round); }
.bk-sample { margin-top: 9px; color: var(--text); font-size: 13.5px; line-height: 1.7; white-space: pre-wrap; }
.bk-ocr-open { justify-self: end; border: 0; background: transparent; color: var(--accent); cursor: pointer; font: 12.5px/1.4 var(--round); padding: 1px 3px; }
.bk-ocr-list { display: grid; gap: 12px; }
.bk-ocr-item { display: grid; gap: 5px; }
.bk-ocr-item span { color: var(--muted); font: 12px/1.4 var(--round); }
.bk-ocr-item textarea { width: 100%; min-height: 72px; resize: vertical; box-sizing: border-box; border: 1px solid var(--border); border-radius: 10px; padding: 10px 11px; color: var(--text); background: var(--panel); font: 14px/1.65 var(--round); }
.bk-fields { display: grid; gap: 11px; margin-top: 20px; }
.bk-field label { display: block; margin: 0 0 5px 2px; color: var(--muted); font: 12px/1.3 var(--round); }
.bk-field select, .bk-field input {
  width: 100%; border: 1px solid var(--border); border-radius: 14px;
  background: var(--panel); color: var(--text); padding: 11px 12px;
  font: 14px/1.3 var(--round); outline: none;
}
.bk-same {
  display: flex; align-items: center; gap: 9px; color: var(--muted);
  font: 12.5px/1.5 var(--round); cursor: pointer;
}
.bk-same input { accent-color: var(--accent); }

@media (min-width: 720px) {
  #booksBody { padding-left: max(24px, calc((100vw - 760px)/2)); padding-right: max(24px, calc((100vw - 760px)/2)); }
  .bk-list { grid-template-columns: repeat(2, minmax(0,1fr)); }
}

@media (prefers-color-scheme: dark) {
  .bk-error { color: #E2A18B; }
}