:root {
  color-scheme: dark;
  --bg: #0b1020;
  --surface: #121a2d;
  --surface-2: #19233b;
  --surface-3: #243252;
  --text: #edf3ff;
  --muted: #9ba9c8;
  --accent: #7c9cff;
  --accent-2: #b38cff;
  --danger: #ff8c9e;
  --border: rgba(255, 255, 255, .12);
  --shadow: 0 24px 70px rgba(0, 0, 0, .32);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; min-width: 320px; background: radial-gradient(circle at top right, #182442 0, var(--bg) 45%); color: var(--text); }
button, input { font: inherit; }
button, label { -webkit-tap-highlight-color: transparent; }
.app-header, .app-shell, .app-footer { width: min(1440px, calc(100% - 40px)); margin-inline: auto; }
.app-header { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 42px 0 28px; }
.eyebrow { margin: 0 0 8px; color: var(--accent); font-size: .7rem; font-weight: 800; letter-spacing: .18em; }
h1 { margin: 0; font-size: clamp(2rem, 4vw, 3.8rem); letter-spacing: -.06em; line-height: .95; }
.subtitle { max-width: 640px; margin: 16px 0 0; color: var(--muted); line-height: 1.6; }
.upload-button, .secondary-button { display: inline-flex; align-items: center; gap: 8px; cursor: pointer; border-radius: 12px; padding: 12px 17px; color: #091020; background: linear-gradient(135deg, #a8bbff, #d0aaff); font-weight: 800; box-shadow: 0 8px 30px rgba(124, 156, 255, .25); transition: transform .2s, filter .2s; }
.upload-button:hover, .secondary-button:hover { transform: translateY(-2px); filter: brightness(1.08); }
.app-shell { overflow: hidden; border: 1px solid var(--border); border-radius: 22px; background: rgba(18, 26, 45, .78); box-shadow: var(--shadow); backdrop-filter: blur(16px); }
.toolbar { display: flex; align-items: center; gap: 18px; padding: 13px 16px; border-bottom: 1px solid var(--border); background: rgba(255,255,255,.025); }
.toolbar-group { display: flex; gap: 7px; }
.toolbar-group--right { margin-left: auto; }
.icon-button { display: inline-grid; place-items: center; width: 38px; height: 38px; padding: 0; border: 1px solid var(--border); border-radius: 10px; color: var(--text); background: var(--surface-2); cursor: pointer; transition: background .2s, transform .2s; }
.icon-button:hover:not(:disabled) { background: var(--surface-3); transform: translateY(-1px); }
.icon-button:disabled { cursor: not-allowed; opacity: .35; }
.page-jump { display: flex; align-items: center; gap: 12px; min-width: 240px; color: var(--muted); font-size: .85rem; }
.page-jump input { width: min(280px, 25vw); accent-color: var(--accent); }
.page-jump output { min-width: 64px; color: var(--text); font-variant-numeric: tabular-nums; }
.status { min-height: 25px; padding: 12px 20px 0; color: var(--muted); font-size: .85rem; }
.error { margin: 10px 20px 0; padding: 11px 13px; border: 1px solid rgba(255, 140, 158, .35); border-radius: 10px; color: var(--danger); background: rgba(255, 140, 158, .08); }
.reader-layout { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 20px; min-height: 700px; padding: 20px; }
.toc-panel { align-self: start; max-height: 700px; overflow: auto; padding: 16px; border: 1px solid var(--border); border-radius: 16px; background: rgba(0,0,0,.12); }
.panel-heading { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.panel-heading h2 { margin: 0; font-size: 1rem; }
.panel-heading span { display: grid; place-items: center; min-width: 24px; height: 24px; border-radius: 99px; color: #111827; background: var(--accent); font-size: .72rem; font-weight: 800; }
.toc-list { display: grid; gap: 5px; }
.toc-item { width: 100%; padding: 9px 10px; border: 0; border-radius: 8px; text-align: left; color: var(--muted); background: transparent; cursor: pointer; font-size: .78rem; line-height: 1.35; }
.toc-item:hover, .toc-item[aria-current="true"] { color: var(--text); background: var(--surface-3); }
.muted { color: var(--muted); font-size: .8rem; line-height: 1.5; }
.reader-stage { position: relative; display: grid; place-items: center; min-height: 650px; overflow: hidden; border: 1px solid var(--border); border-radius: 16px; background: radial-gradient(circle, #28385d 0, #12192b 65%); }
.book { width: min(1280px, 100%); min-height: 580px; }
.reader-stage:fullscreen { width: 100vw; height: 100vh; min-height: 100vh; border: 0; border-radius: 0; }
.reader-stage:fullscreen .book { width: min(1800px, 100vw); height: calc(100vh - 24px); min-height: 0; }
.book .page { display: flex; align-items: center; justify-content: center; overflow: hidden; background: #fff; }
.book .page canvas { display: block; width: 100%; height: 100%; object-fit: contain; }
.empty-state { position: absolute; inset: 0; display: grid; place-content: center; justify-items: center; padding: 24px; text-align: center; }
.empty-state[hidden], .loading[hidden] { display: none; }
.empty-icon { display: grid; place-items: center; width: 70px; height: 70px; margin-bottom: 16px; border: 1px solid rgba(168,187,255,.35); border-radius: 22px; color: var(--accent); background: rgba(124,156,255,.1); font-size: 2rem; }
.empty-state h2 { margin: 0; font-size: 1.25rem; }
.empty-state p { margin: 10px 0 20px; color: var(--muted); }
.secondary-button { color: var(--text); background: var(--surface-3); box-shadow: none; }
.loading { position: absolute; inset: 0; display: grid; place-content: center; justify-items: center; background: rgba(11,16,32,.78); }
.spinner { width: 34px; height: 34px; border: 3px solid rgba(255,255,255,.15); border-top-color: var(--accent); border-radius: 50%; animation: spin .8s linear infinite; }
.loading p { color: var(--muted); }
@keyframes spin { to { transform: rotate(360deg); } }
.app-footer { display: flex; justify-content: space-between; padding: 18px 0 34px; color: var(--muted); font-size: .75rem; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
@media (max-width: 850px) {
  .app-header { align-items: flex-start; flex-direction: column; }
  .upload-button { align-self: stretch; justify-content: center; }
  .toolbar { flex-wrap: wrap; }
  .toolbar-group--right { margin-left: 0; }
  .page-jump { order: 3; width: 100%; }
  .page-jump input { width: 100%; }
  .reader-layout { grid-template-columns: 1fr; min-height: 0; }
  .toc-panel { max-height: 180px; order: 2; }
  .reader-stage { min-height: 72vh; }
  .book { min-height: 72vh; }
  .app-footer { flex-direction: column; gap: 8px; }
}
@media (max-width: 480px) {
  .app-header, .app-shell, .app-footer { width: min(100% - 24px, 1440px); }
  .app-header { padding-top: 26px; }
  .reader-layout { padding: 10px; }
  .reader-stage { min-height: 65vh; }
  .book { min-height: 65vh; }
  .toolbar { gap: 8px; padding: 10px; }
  .icon-button { width: 34px; height: 34px; }
}