:root {
  font-family: Inter, ui-rounded, "SF Pro Rounded", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #15243b;
  background: #f4f7fb;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  --blue: #2667e8;
  --blue-dark: #164fc3;
  --ink: #15243b;
  --muted: #66758a;
  --line: #dce4ef;
  --card: #ffffff;
}

* { box-sizing: border-box; }
body { margin: 0; min-width: 320px; min-height: 100vh; background: #f4f7fb; }
button, input { font: inherit; }
button { -webkit-tap-highlight-color: transparent; }
button:focus-visible, input:focus-visible { outline: 3px solid rgba(38, 103, 232, 0.25); outline-offset: 2px; }

.app-shell { min-height: 100vh; }
.app-header {
  height: 72px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 24px;
  color: white;
  background: linear-gradient(135deg, #225dd1, #2f73f2);
  box-shadow: 0 8px 24px rgba(29, 76, 157, 0.18);
}
.app-header strong { display: block; font-size: 19px; }
.app-header span { display: block; margin-top: 1px; font-size: 12px; opacity: 0.82; }
.brand-mark { width: 40px; height: 40px; display: grid; place-items: center; border-radius: 13px; background: white; color: var(--blue); font-size: 22px; font-weight: 900; box-shadow: 0 5px 12px rgba(0,0,0,.12); }

.home-page { width: min(980px, 100%); margin: 0 auto; padding: 28px 20px 64px; }
.hero-card {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: end;
  gap: 24px;
  padding: 34px;
  border-radius: 28px;
  color: white;
  background: linear-gradient(135deg, #1e56c5 0%, #397ff5 65%, #74a9ff 100%);
  box-shadow: 0 18px 50px rgba(31, 93, 201, 0.24);
}
.hero-card h1 { margin: 8px 0 12px; font-size: clamp(32px, 6vw, 54px); line-height: 1.08; letter-spacing: -0.045em; }
.hero-description { max-width: 610px; margin: 0; color: rgba(255,255,255,.86); line-height: 1.65; }
.eyebrow { margin: 0; font-size: 12px; font-weight: 850; letter-spacing: .12em; text-transform: uppercase; color: #6e7c91; }
.hero-card .eyebrow { color: #d8e7ff; }

.primary-button, .secondary-button, .image-picker, .icon-button, .text-button { border: 0; cursor: pointer; }
.primary-button { min-height: 48px; padding: 0 20px; border-radius: 14px; color: white; background: var(--blue); font-weight: 800; box-shadow: 0 9px 22px rgba(38,103,232,.22); }
.primary-button:hover { background: var(--blue-dark); }
.primary-button:disabled, .secondary-button:disabled { cursor: wait; opacity: .6; }
.hero-button { min-width: 145px; background: white; color: #1c5bcf; box-shadow: 0 10px 24px rgba(7,47,119,.2); }
.hero-button:hover { background: #eef5ff; }
.secondary-button { min-height: 46px; padding: 0 18px; border-radius: 13px; color: #2e4564; background: #eaf0f7; font-weight: 750; }

.library-section { margin-top: 34px; }
.section-heading { display: flex; align-items: end; justify-content: space-between; margin-bottom: 16px; }
.section-heading h2 { margin: 4px 0 0; font-size: 28px; }
.book-count { padding: 7px 11px; border-radius: 999px; color: #48617f; background: #e7edf5; font-size: 13px; font-weight: 800; }
.book-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }

.book-card { display: grid; grid-template-columns: 132px 1fr; min-height: 180px; overflow: hidden; border: 1px solid #e2e9f2; border-radius: 22px; background: white; box-shadow: 0 10px 28px rgba(46,74,112,.08); }
.book-cover-wrap { padding: 12px; background: #eef3fa; }
.book-cover, .book-cover-placeholder { width: 100%; height: 100%; min-height: 156px; border-radius: 14px; object-fit: cover; }
.book-cover-placeholder { display: grid; place-items: center; background: #dce7f6; font-size: 42px; }
.book-card-body { display: flex; flex-direction: column; justify-content: space-between; min-width: 0; padding: 20px; }
.book-title-row { display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; }
.book-title-row h2 { margin: 0; overflow: hidden; color: var(--ink); font-size: 22px; text-overflow: ellipsis; white-space: nowrap; }
.book-title-row p { margin: 5px 0 0; color: var(--muted); font-size: 14px; }
.icon-button { min-height: 36px; padding: 0 11px; border-radius: 10px; color: #596b82; background: #eef2f7; font-size: 12px; font-weight: 800; }
.icon-button.danger:hover { color: #b42318; background: #fff0ee; }
.progress-track { width: 100%; height: 9px; overflow: hidden; border-radius: 999px; background: #e8eef6; }
.progress-value { height: 100%; border-radius: inherit; background: linear-gradient(90deg, #2e73ed, #67a0ff); }
.book-meta-row { display: flex; justify-content: space-between; gap: 10px; margin-top: 9px; color: #718096; font-size: 12px; }

.empty-state { padding: 52px 20px; border: 2px dashed #d6e0ec; border-radius: 24px; text-align: center; background: rgba(255,255,255,.72); }
.empty-state h3 { margin: 10px 0 8px; font-size: 21px; }
.empty-state p { margin: 0 auto 20px; max-width: 470px; color: var(--muted); line-height: 1.6; }
.empty-icon { font-size: 44px; }

.dialog-backdrop { position: fixed; inset: 0; z-index: 50; display: grid; place-items: center; padding: 16px; background: rgba(12, 25, 45, .66); backdrop-filter: blur(5px); }
.dialog-panel { width: min(600px, 100%); max-height: calc(100vh - 32px); overflow-y: auto; padding: 24px; border-radius: 24px; background: white; box-shadow: 0 30px 90px rgba(0,0,0,.32); }
.dialog-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; margin-bottom: 22px; }
.dialog-header h2 { margin: 4px 0 0; font-size: 27px; }
.field-label { display: block; margin-bottom: 8px; color: #30445f; font-size: 14px; font-weight: 800; }
.text-input { width: 100%; height: 50px; padding: 0 14px; border: 1px solid #cad5e2; border-radius: 13px; color: var(--ink); background: white; }
.image-picker { width: 100%; min-height: 130px; display: grid; place-items: center; align-content: center; gap: 5px; margin-top: 16px; padding: 18px; border: 2px dashed #9fb7d6; border-radius: 17px; color: #2f5d98; background: #f3f7fc; }
.image-picker:hover { background: #eaf3ff; }
.image-picker-icon { font-size: 28px; line-height: 1; }
.image-picker small { color: #6c8099; }
.preview-summary { display: flex; align-items: center; justify-content: space-between; margin: 18px 0 10px; }
.text-button { padding: 5px 0; color: #2765ce; background: transparent; font-weight: 800; }
.preview-grid { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 9px; }
.preview-card { position: relative; margin: 0; aspect-ratio: 3/4; overflow: hidden; border-radius: 11px; background: #dfe7f1; }
.preview-card img { width: 100%; height: 100%; object-fit: cover; }
.preview-card figcaption { position: absolute; right: 5px; bottom: 5px; min-width: 22px; padding: 3px 6px; border-radius: 999px; color: white; background: rgba(14,27,47,.74); text-align: center; font-size: 11px; font-weight: 800; }
.form-error { margin: 14px 0 0; color: #b42318; font-size: 14px; font-weight: 700; }
.dialog-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 22px; }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }

@media (max-width: 760px) {
  .app-header { height: 64px; padding: 0 16px; }
  .home-page { padding: 18px 14px 40px; }
  .hero-card { grid-template-columns: 1fr; padding: 25px 21px; border-radius: 23px; }
  .hero-button { width: 100%; }
  .book-grid { grid-template-columns: 1fr; }
  .book-card { grid-template-columns: 112px 1fr; min-height: 160px; }
  .book-cover, .book-cover-placeholder { min-height: 136px; }
  .book-card-body { padding: 16px; }
  .book-title-row h2 { font-size: 19px; }
  .preview-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .dialog-panel { padding: 20px; border-radius: 20px; }
}

@media (max-width: 420px) {
  .book-card { grid-template-columns: 98px 1fr; }
  .book-cover-wrap { padding: 9px; }
  .book-cover, .book-cover-placeholder { min-height: 132px; }
  .book-meta-row { flex-direction: column; gap: 3px; }
  .preview-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

.book-card-clickable { cursor: pointer; transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease; }
.book-card-clickable:hover { transform: translateY(-3px); border-color: #b8cbed; box-shadow: 0 16px 36px rgba(46,74,112,.14); }
.book-card-clickable:focus-visible { outline: 3px solid rgba(38,103,232,.28); outline-offset: 3px; }

.reader-page { min-height: 100vh; padding: 18px 18px 40px; background: linear-gradient(180deg, #eaf1fb 0%, #f7f9fc 44%, #f4f7fb 100%); }
.reader-topbar { width: min(1060px, 100%); min-height: 64px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 14px; margin: 0 auto 16px; padding: 10px 14px; border: 1px solid rgba(202,214,230,.88); border-radius: 18px; background: rgba(255,255,255,.9); box-shadow: 0 10px 28px rgba(47,72,108,.09); backdrop-filter: blur(10px); }
.reader-back-button { min-height: 40px; padding: 0 13px; border: 0; border-radius: 11px; color: #2e527e; background: #eaf1f9; font-weight: 850; cursor: pointer; }
.reader-title-block { min-width: 0; text-align: center; }
.reader-title-block strong { display: block; overflow: hidden; font-size: 18px; text-overflow: ellipsis; white-space: nowrap; }
.reader-title-block span { display: block; margin-top: 2px; color: var(--muted); font-size: 12px; }
.reader-progress-pill { min-width: 50px; padding: 7px 10px; border-radius: 999px; color: #1c59c2; background: #e6efff; text-align: center; font-size: 12px; font-weight: 900; }
.reader-stage { position: relative; width: min(920px, 100%); min-height: 360px; display: grid; place-items: center; margin: 0 auto; overflow: hidden; border: 1px solid #d7e1ee; border-radius: 24px; background: #dfe7f0; box-shadow: 0 20px 55px rgba(42,69,106,.16); }
.reader-image { display: block; width: 100%; max-height: calc(100vh - 230px); object-fit: contain; background: #edf2f7; }
.reader-empty-image { min-height: 420px; display: grid; place-items: center; color: var(--muted); }
.reader-page-badge { position: absolute; right: 13px; bottom: 13px; min-width: 38px; padding: 8px 11px; border-radius: 999px; color: white; background: rgba(15,31,53,.72); text-align: center; font-size: 13px; font-weight: 900; backdrop-filter: blur(6px); }
.reader-progress-track { width: min(920px, 100%); height: 8px; margin: 16px auto 0; overflow: hidden; border-radius: 999px; background: #dfe7f1; }
.reader-progress-value { height: 100%; border-radius: inherit; background: linear-gradient(90deg, #2e73ed, #72a9ff); transition: width .25s ease; }
.reader-controls { width: min(920px, 100%); display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 16px auto 0; }
.reader-nav-button { width: 100%; }
.reader-nav-button:disabled { cursor: not-allowed; opacity: .45; }
.reader-help { width: min(920px, 100%); margin: 15px auto 0; color: #6e7d91; text-align: center; font-size: 13px; }
.reader-message { width: min(680px, calc(100% - 32px)); margin: 80px auto; padding: 40px 24px; border: 1px solid #d9e3ef; border-radius: 22px; background: white; text-align: center; box-shadow: 0 15px 38px rgba(44,70,104,.1); }
.reader-message h2 { margin-top: 0; }

@media (max-width: 600px) {
  .reader-page { padding: 10px 10px 28px; }
  .reader-topbar { grid-template-columns: auto minmax(0,1fr) auto; gap: 8px; margin-bottom: 10px; padding: 8px; border-radius: 15px; }
  .reader-back-button { min-height: 38px; padding: 0 10px; font-size: 13px; }
  .reader-title-block strong { font-size: 15px; }
  .reader-progress-pill { min-width: 44px; padding: 6px 8px; font-size: 11px; }
  .reader-stage { min-height: 300px; border-radius: 17px; }
  .reader-image { max-height: calc(100vh - 205px); }
  .reader-controls { grid-template-columns: 1fr 1fr; gap: 9px; }
  .reader-nav-button { min-height: 48px; padding: 0 10px; font-size: 14px; }
}

/* v0.4 reading layer */
.reading-text-layer { position: absolute; left: 14px; right: 14px; bottom: 14px; z-index: 4; max-height: 48%; overflow-y: auto; padding: 14px; border: 1px solid rgba(255,255,255,.4); border-radius: 16px; background: rgba(10,24,45,.72); color: white; backdrop-filter: blur(9px); box-shadow: 0 10px 30px rgba(0,0,0,.24); }
.reader-sentence { margin: 0 0 8px; padding: 8px 9px; border-radius: 10px; line-height: 1.8; cursor: pointer; transition: background .15s ease; }
.reader-sentence:last-child { margin-bottom: 0; }
.reader-sentence:hover, .reader-sentence:focus-visible { background: rgba(255,255,255,.12); outline: none; }
.reader-word { display: inline; padding: 2px 3px; border: 0; border-radius: 6px; color: inherit; background: transparent; font: inherit; font-weight: 760; cursor: pointer; }
.reader-word:hover, .reader-word:focus-visible { color: #133c80; background: #dfeaff; outline: none; }
.reader-word:disabled { cursor: default; }
.reading-toolbar { width: min(920px, 100%); display: flex; flex-wrap: wrap; align-items: center; gap: 9px; margin: 14px auto 0; padding: 12px; border: 1px solid #d8e2ef; border-radius: 17px; background: rgba(255,255,255,.92); box-shadow: 0 9px 24px rgba(42,69,106,.08); }
.reading-toolbar .primary-button, .reading-toolbar .secondary-button { min-height: 42px; }
.speed-control { margin-left: auto; display: grid; grid-template-columns: auto minmax(100px, 170px) 48px; align-items: center; gap: 8px; color: #455d7a; font-size: 13px; font-weight: 800; }
.speed-control input { width: 100%; }
.speed-control span { text-align: right; font-variant-numeric: tabular-nums; }
.text-editor-panel { width: min(680px, 100%); }
.editor-guide { margin: -7px 0 14px; color: var(--muted); line-height: 1.55; }
.page-textarea { width: 100%; min-height: 250px; resize: vertical; padding: 15px; border: 1px solid #c9d5e3; border-radius: 14px; color: var(--ink); background: #fbfdff; font: inherit; font-size: 16px; line-height: 1.65; }
.page-textarea:focus { outline: 3px solid rgba(38,103,232,.18); border-color: #6e9fea; }

@media (max-width: 600px) {
  .reading-text-layer { left: 8px; right: 8px; bottom: 8px; max-height: 52%; padding: 10px; border-radius: 13px; font-size: 15px; }
  .reader-sentence { padding: 6px; line-height: 1.68; }
  .reading-toolbar { gap: 7px; padding: 9px; }
  .reading-toolbar .primary-button, .reading-toolbar .secondary-button { flex: 1 1 calc(50% - 7px); min-height: 45px; padding: 0 10px; font-size: 13px; }
  .speed-control { width: 100%; margin-left: 0; grid-template-columns: auto 1fr 46px; padding: 5px 2px 0; }
}

/* v0.5 AI Vision and coordinate overlays */
.reader-image-frame { position: relative; display: inline-block; max-width: 100%; line-height: 0; }
.reader-image-frame .reader-image { width: auto; max-width: 100%; height: auto; max-height: calc(100vh - 230px); }
.coordinate-overlay { position: absolute; inset: 0; z-index: 5; pointer-events: none; }
.sentence-hitbox, .word-hitbox { position: absolute; margin: 0; padding: 0; border: 0; background: transparent; pointer-events: auto; cursor: pointer; }
.sentence-hitbox { z-index: 1; border-radius: 8px; }
.word-hitbox { z-index: 2; min-width: 12px; min-height: 12px; border-radius: 6px; }
.coordinate-overlay.show-boxes .sentence-hitbox { border: 2px solid rgba(255,174,0,.64); background: rgba(255,199,76,.08); }
.coordinate-overlay.show-boxes .word-hitbox { border: 2px solid rgba(31,111,235,.76); background: rgba(70,143,255,.16); }
.word-hitbox span { position: absolute; left: 50%; bottom: calc(100% + 3px); transform: translateX(-50%); display: none; padding: 3px 6px; border-radius: 6px; color: white; background: rgba(12,31,60,.88); font-size: 11px; line-height: 1.2; white-space: nowrap; }
.word-hitbox:hover span, .word-hitbox:focus-visible span { display: block; }
.word-hitbox:active { background: rgba(31,111,235,.34); }
.ai-button { min-height: 46px; padding: 0 18px; border: 0; border-radius: 13px; color: #663c00; background: linear-gradient(135deg, #ffe39a, #ffc85b); font-weight: 900; box-shadow: 0 8px 20px rgba(196,128,0,.18); cursor: pointer; }
.ai-button:disabled { cursor: wait; opacity: .65; }
.analysis-mask { position: absolute; inset: 0; z-index: 9; display: flex; align-items: center; justify-content: center; gap: 10px; color: white; background: rgba(12,31,60,.72); font-weight: 850; backdrop-filter: blur(4px); }
.analysis-spinner { width: 24px; height: 24px; border: 3px solid rgba(255,255,255,.35); border-top-color: white; border-radius: 50%; animation: analysis-spin .8s linear infinite; }
@keyframes analysis-spin { to { transform: rotate(360deg); } }
.analysis-error { width: min(920px,100%); margin: 12px auto 0; padding: 12px 14px; border: 1px solid #f0b8b2; border-radius: 12px; color: #98291e; background: #fff1ef; font-size: 13px; font-weight: 750; }
.api-key-panel { width: min(560px,100%); }

@media (max-width: 600px) {
  .reader-image-frame .reader-image { max-height: calc(100vh - 205px); }
  .ai-button { flex: 1 1 100%; min-height: 47px; }
  .coordinate-overlay.show-boxes .sentence-hitbox { border-width: 1px; }
  .coordinate-overlay.show-boxes .word-hitbox { border-width: 1.5px; }
}
.voice-control { display: grid; grid-template-columns: auto minmax(190px, 260px); align-items: center; gap: 8px; color: #455d7a; font-size: 13px; font-weight: 800; }
.voice-control select { min-height: 40px; padding: 0 34px 0 11px; border: 1px solid #cbd8e8; border-radius: 11px; color: #234567; background: #f8fbff; font: inherit; cursor: pointer; }
.speech-notice { width: min(920px, 100%); margin: 12px auto 0; padding: 11px 14px; border: 1px solid #c9dcfa; border-radius: 13px; color: #28558d; background: #eef5ff; text-align: center; font-size: 13px; font-weight: 700; }
@media (max-width: 720px) {
  .voice-control { width: 100%; grid-template-columns: auto 1fr; }
  .voice-control select { width: 100%; }
}

/* v0.9 immersive full-screen reader */
.reader-top-actions { display: flex; align-items: center; justify-content: flex-end; gap: 8px; }
.fullscreen-button { min-height: 40px; padding: 0 13px; border: 0; border-radius: 11px; color: white; background: #173f78; font-weight: 850; cursor: pointer; white-space: nowrap; }
.fullscreen-button:hover { background: #0f315f; }

.reader-fullscreen { position: fixed; inset: 0; z-index: 9999; display: grid; grid-template-rows: 1fr; width: 100vw; height: 100dvh; padding: 0; overflow: hidden; background: #05090f; }
.reader-fullscreen .reader-topbar,
.reader-fullscreen > .reading-toolbar,
.reader-fullscreen > .reader-help,
.reader-fullscreen > .analysis-error,
.reader-fullscreen > .speech-notice,
.reader-fullscreen > .reader-progress-track,
.reader-fullscreen > .reader-controls { display: none; }
.reader-fullscreen .reader-stage { width: 100vw; height: 100dvh; min-height: 0; margin: 0; border: 0; border-radius: 0; background: #05090f; box-shadow: none; }
.reader-fullscreen .reader-image-frame { display: flex; align-items: center; justify-content: center; width: 100%; height: 100%; }
.reader-fullscreen .reader-image-frame .reader-image { width: 100%; height: 100%; max-width: 100%; max-height: 100dvh; object-fit: contain; background: #05090f; }
.reader-fullscreen .reader-page-badge { right: max(14px, env(safe-area-inset-right)); bottom: calc(92px + env(safe-area-inset-bottom)); opacity: .8; transition: opacity .22s ease; }
.reader-fullscreen.controls-hidden .reader-page-badge { opacity: 0; }
.reader-fullscreen .analysis-mask { border-radius: 0; }

.fullscreen-top-controls { position: fixed; top: 0; left: 0; right: 0; z-index: 10020; display: grid; grid-template-columns: 48px minmax(0,1fr) 48px; align-items: center; gap: 10px; padding: calc(10px + env(safe-area-inset-top)) max(12px, env(safe-area-inset-right)) 10px max(12px, env(safe-area-inset-left)); background: linear-gradient(180deg, rgba(0,0,0,.78), rgba(0,0,0,0)); transition: opacity .22s ease, transform .22s ease; }
.fullscreen-round-button { width: 44px; height: 44px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.25); border-radius: 50%; color: white; background: rgba(14,27,45,.72); font-size: 20px; font-weight: 900; cursor: pointer; backdrop-filter: blur(10px); }
.fullscreen-page-title { min-width: 0; color: white; text-align: center; text-shadow: 0 2px 8px rgba(0,0,0,.7); }
.fullscreen-page-title strong { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 16px; }
.fullscreen-page-title span { display: block; margin-top: 2px; font-size: 12px; opacity: .82; }

.fullscreen-bottom-controls { position: fixed; left: 50%; bottom: calc(12px + env(safe-area-inset-bottom)); z-index: 10020; transform: translateX(-50%); width: min(720px, calc(100vw - 24px)); display: grid; grid-template-columns: repeat(6, minmax(0,1fr)); gap: 7px; padding: 8px; border: 1px solid rgba(255,255,255,.22); border-radius: 22px; background: rgba(9,20,36,.76); box-shadow: 0 14px 40px rgba(0,0,0,.42); backdrop-filter: blur(14px); transition: opacity .22s ease, transform .22s ease; }
.fullscreen-bottom-controls button { min-width: 0; min-height: 58px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px; padding: 5px 4px; border: 0; border-radius: 15px; color: white; background: rgba(255,255,255,.1); font-size: 23px; font-weight: 900; cursor: pointer; }
.fullscreen-bottom-controls button:hover { background: rgba(255,255,255,.2); }
.fullscreen-bottom-controls button:disabled { cursor: not-allowed; opacity: .32; }
.fullscreen-bottom-controls button span { font-size: 10px; font-weight: 800; white-space: nowrap; }
.fullscreen-tap-hint { position: fixed; left: 50%; bottom: calc(88px + env(safe-area-inset-bottom)); z-index: 10019; transform: translateX(-50%); margin: 0; padding: 6px 10px; border-radius: 999px; color: rgba(255,255,255,.82); background: rgba(0,0,0,.48); font-size: 11px; white-space: nowrap; transition: opacity .22s ease; }
.reader-fullscreen.controls-hidden .fullscreen-top-controls { opacity: 0; pointer-events: none; transform: translateY(-20px); }
.reader-fullscreen.controls-hidden .fullscreen-bottom-controls { opacity: 0; pointer-events: none; transform: translate(-50%, 24px); }
.reader-fullscreen.controls-hidden .fullscreen-tap-hint { opacity: 0; }
.reader-fullscreen .coordinate-overlay.show-boxes .word-hitbox { border-color: rgba(83,164,255,.9); background: rgba(70,143,255,.2); }

@media (max-width: 600px) {
  .reader-topbar { grid-template-columns: auto minmax(0,1fr); }
  .reader-top-actions { grid-column: 1 / -1; width: 100%; justify-content: space-between; }
  .fullscreen-button { flex: 1; }
  .reader-fullscreen .reader-stage { border-radius: 0; }
  .fullscreen-bottom-controls { grid-template-columns: repeat(6, minmax(0,1fr)); gap: 4px; width: calc(100vw - 12px); padding: 6px; border-radius: 18px; }
  .fullscreen-bottom-controls button { min-height: 54px; border-radius: 13px; font-size: 21px; }
  .fullscreen-bottom-controls button span { font-size: 9px; }
  .fullscreen-tap-hint { display: none; }
}

@media (orientation: landscape) and (max-height: 600px) {
  .fullscreen-bottom-controls { left: auto; right: calc(8px + env(safe-area-inset-right)); bottom: 50%; transform: translateY(50%); width: 74px; grid-template-columns: 1fr; border-radius: 20px; }
  .fullscreen-bottom-controls button { min-height: 48px; }
  .reader-fullscreen.controls-hidden .fullscreen-bottom-controls { transform: translate(24px, 50%); }
  .reader-fullscreen .reader-page-badge { right: calc(94px + env(safe-area-inset-right)); bottom: 12px; }
}

/* v2 analysis queue */
.analysis-mask small {
  display: block;
  margin-top: .5rem;
  font-size: .82rem;
  font-weight: 800;
  opacity: .8;
}

/* v2.1 precise touch overlay and iOS/iPadOS reader refinements */
.reader-image-frame,
.reader-image-frame .reader-image { -webkit-user-select: none; user-select: none; }
.coordinate-overlay { touch-action: manipulation; }
.sentence-hitbox, .word-hitbox { -webkit-tap-highlight-color: transparent; touch-action: manipulation; }
.coordinate-overlay.show-boxes .sentence-hitbox {
  border: 1px dashed rgba(255, 166, 0, .78);
  background: transparent;
  box-shadow: 0 0 0 1px rgba(255,255,255,.42);
}
.coordinate-overlay.show-boxes .word-hitbox {
  border: 1.5px solid rgba(31, 111, 235, .86);
  background: transparent;
  box-shadow: 0 0 0 1px rgba(255,255,255,.55);
}
.word-hitbox:active,
.word-hitbox:focus-visible {
  background: transparent;
  outline: 3px solid rgba(31,111,235,.28);
  outline-offset: 1px;
}
.word-hitbox span {
  pointer-events: none;
  bottom: calc(100% + 5px);
}

/* The fullscreen frame must shrink-wrap the rendered image. This keeps the
   0-1000 OCR coordinate system aligned even when object-fit introduces bars. */
.reader-fullscreen .reader-stage {
  display: flex;
  align-items: center;
  justify-content: center;
}
.reader-fullscreen .reader-image-frame {
  position: relative;
  display: inline-block;
  width: auto;
  height: auto;
  max-width: 100vw;
  max-height: 100dvh;
  line-height: 0;
}
.reader-fullscreen .reader-image-frame .reader-image {
  display: block;
  width: auto;
  height: auto;
  max-width: 100vw;
  max-height: 100dvh;
  object-fit: contain;
  background: #05090f;
}
.reader-fullscreen .coordinate-overlay {
  position: absolute;
  inset: 0;
}
.reader-fullscreen .coordinate-overlay.show-boxes .word-hitbox {
  background: transparent;
  border-color: rgba(83,164,255,.95);
}

html, body, #root { min-height: 100%; }
body { min-height: 100dvh; }
@supports (-webkit-touch-callout: none) {
  body { min-height: -webkit-fill-available; }
  .reader-fullscreen { height: -webkit-fill-available; }
}

.pause-resume-button:disabled {
  opacity: 0.48;
  cursor: not-allowed;
}

/* v2.3 pronunciation evaluation */
.practice-panel {
  margin: 14px auto;
  width: min(920px, calc(100% - 24px));
  padding: 16px;
  border: 1px solid #cbd5e1;
  border-radius: 18px;
  background: rgba(255,255,255,.96);
  box-shadow: 0 10px 28px rgba(15,23,42,.10);
}
.practice-panel-header,
.practice-status-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.practice-panel-header span,
.practice-status-row small { color: #64748b; font-size: .84rem; }
.practice-target {
  margin: 12px 0;
  padding: 14px;
  border-radius: 14px;
  background: #eff6ff;
  color: #172554;
  font-size: clamp(1.05rem, 3vw, 1.45rem);
  font-weight: 750;
  line-height: 1.45;
  text-align: center;
}
.practice-status-row { min-height: 34px; font-weight: 700; color: #334155; }
.recording-status { display: inline-flex; align-items: center; gap: 8px; color: #b91c1c; }
.recording-status i {
  width: 12px; height: 12px; border-radius: 999px; background: #ef4444;
  box-shadow: 0 0 0 0 rgba(239,68,68,.45); animation: recordingPulse 1.2s infinite;
}
@keyframes recordingPulse { 70% { box-shadow: 0 0 0 10px rgba(239,68,68,0); } 100% { box-shadow: 0 0 0 0 rgba(239,68,68,0); } }
.finish-speaking-button {
  display: block;
  width: 100%;
  margin-top: 10px;
  padding: 13px 16px;
  border: 0;
  border-radius: 13px;
  background: #dc2626;
  color: white;
  font-weight: 800;
  font-size: 1rem;
}
.practice-result-grid {
  margin-top: 13px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 9px;
}
.practice-result-grid > div {
  padding: 12px 8px;
  border-radius: 13px;
  background: #f8fafc;
  text-align: center;
}
.practice-result-grid strong { display: block; color: #1d4ed8; font-size: 1.5rem; }
.practice-result-grid span { color: #64748b; font-size: .76rem; }
.practice-result-grid p { grid-column: 1 / -1; margin: 0; font-size: .9rem; color: #334155; }
.practice-passed { border-color: #86efac; background: #f0fdf4; }
.practice-retry { border-color: #fcd34d; background: #fffbeb; }
.practice-recording { border-color: #fca5a5; }
.reader-fullscreen .practice-panel {
  position: fixed;
  left: 50%;
  bottom: calc(92px + env(safe-area-inset-bottom));
  transform: translateX(-50%);
  z-index: 35;
  width: min(760px, calc(100% - 24px));
  max-height: 34vh;
  overflow: auto;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(12px);
}
.reader-fullscreen.controls-hidden .practice-panel { opacity: .18; pointer-events: none; }
@media (max-width: 520px) {
  .practice-result-grid { grid-template-columns: repeat(3, 1fr); gap: 5px; }
  .practice-result-grid > div { padding: 9px 3px; }
  .practice-result-grid strong { font-size: 1.22rem; }
  .practice-result-grid span { font-size: .65rem; }
}

.microphone-permission-hint {
  margin: 0.65rem 0;
  padding: 0.7rem 0.85rem;
  border: 1px solid rgba(37, 99, 235, 0.28);
  border-radius: 0.8rem;
  background: rgba(239, 246, 255, 0.92);
  color: #1e3a8a;
  font-size: 0.9rem;
  line-height: 1.45;
}

/* v2.6 exact resume and page reading position scroll */
.page-reading-scroll {
  width: min(920px, 100%);
  margin: 14px auto 0;
  padding: 13px 15px;
  border: 1px solid #d8e2ef;
  border-radius: 17px;
  background: rgba(255,255,255,.94);
  box-shadow: 0 9px 24px rgba(42,69,106,.07);
}
.page-reading-scroll-header { display: flex; align-items: center; justify-content: space-between; gap: 12px; color: #29496f; font-size: 13px; }
.page-reading-scroll input[type="range"] { width: 100%; margin: 10px 0 5px; accent-color: #2e73ed; cursor: pointer; }
.page-reading-scroll-progress { height: 4px; overflow: hidden; border-radius: 999px; background: #dfe7f1; }
.page-reading-scroll-progress span { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg,#2e73ed,#78abff); transition: width .12s linear; }
.page-reading-scroll p { min-height: 1.5em; margin: 8px 0 0; color: #64758b; font-size: 12px; line-height: 1.45; text-align: center; }

.fullscreen-reading-scroll {
  position: fixed;
  left: 50%;
  bottom: calc(91px + env(safe-area-inset-bottom));
  z-index: 10020;
  transform: translateX(-50%);
  width: min(700px, calc(100vw - 28px));
  display: grid;
  grid-template-columns: auto minmax(0,1fr);
  align-items: center;
  gap: 10px;
  padding: 8px 13px;
  border: 1px solid rgba(255,255,255,.22);
  border-radius: 17px;
  color: white;
  background: rgba(9,20,36,.76);
  box-shadow: 0 10px 30px rgba(0,0,0,.38);
  backdrop-filter: blur(14px);
  transition: opacity .22s ease, transform .22s ease;
}
.fullscreen-reading-scroll div { display: flex; align-items: baseline; gap: 3px; white-space: nowrap; }
.fullscreen-reading-scroll strong { font-size: 16px; }
.fullscreen-reading-scroll span { font-size: 10px; opacity: .78; }
.fullscreen-reading-scroll input { width: 100%; accent-color: #7eb2ff; cursor: pointer; }
.reader-fullscreen.controls-hidden .fullscreen-reading-scroll { opacity: 0; pointer-events: none; transform: translate(-50%,24px); }

@media (max-width: 640px) {
  .page-reading-scroll { padding: 10px 11px; }
  .fullscreen-reading-scroll { bottom: calc(77px + env(safe-area-inset-bottom)); width: calc(100vw - 16px); padding: 6px 10px; }
}

@media (orientation: landscape) and (max-height: 560px) {
  .fullscreen-reading-scroll { left: 12px; right: auto; bottom: 12px; transform: none; width: min(520px, calc(100vw - 110px)); }
  .reader-fullscreen.controls-hidden .fullscreen-reading-scroll { transform: translateY(20px); }
}

/* v2.7 reading tracker */
.reading-follow-panel {
  margin: 16px auto;
  max-width: 980px;
  padding: 16px;
  border-radius: 18px;
  background: #fffdf4;
  border: 2px solid #f1d56a;
  box-shadow: 0 8px 24px rgba(58, 42, 10, 0.08);
}
.reading-follow-header { display:flex; justify-content:space-between; align-items:center; gap:12px; color:#66510d; }
.reading-follow-current {
  margin: 12px 0;
  padding: 16px;
  border-radius: 14px;
  background: #fff;
  font-size: clamp(1.25rem, 3vw, 2rem);
  line-height: 1.55;
  font-weight: 800;
  color: #172033;
  text-align: center;
}
.reading-follow-sentences {
  display:flex;
  gap:8px;
  overflow-x:auto;
  scroll-snap-type:x proximity;
  padding: 4px 2px 10px;
}
.reading-follow-sentences button {
  flex: 0 0 min(78vw, 420px);
  scroll-snap-align:center;
  text-align:left;
  border:1px solid #d9dfeb;
  background:#f7f9fc;
  color:#667085;
  border-radius:12px;
  padding:12px;
  line-height:1.45;
}
.reading-follow-sentences button span { display:inline-grid; place-items:center; width:24px; height:24px; margin-right:8px; border-radius:50%; background:#e6ebf3; font-weight:800; }
.reading-follow-sentences button.is-complete { color:#47705b; background:#eef9f1; border-color:#b9e0c4; }
.reading-follow-sentences button.is-active { color:#172033; background:#fff7c9; border:2px solid #e2b91d; box-shadow:0 5px 14px rgba(181,139,0,.18); font-weight:750; }
.fullscreen-current-sentence {
  position: fixed;
  left: max(12px, env(safe-area-inset-left));
  right: max(12px, env(safe-area-inset-right));
  bottom: calc(92px + env(safe-area-inset-bottom));
  z-index: 40;
  padding: 10px 16px;
  border-radius: 16px;
  background: rgba(10, 15, 25, .82);
  color: white;
  backdrop-filter: blur(10px);
  text-align:center;
  pointer-events:auto;
}
.fullscreen-current-sentence span { display:block; font-size:.78rem; opacity:.75; margin-bottom:4px; }
.fullscreen-current-sentence strong { font-size:clamp(1.1rem, 3vw, 1.8rem); line-height:1.4; }
@media (max-width: 760px) {
  .reading-follow-panel { margin: 12px 8px; padding: 12px; }
  .fullscreen-bottom-controls { overflow-x:auto; justify-content:flex-start; }
  .fullscreen-bottom-controls button { flex:0 0 58px; }
}

/* v3.0 single-screen reader layout */
.reader-page:not(.reader-fullscreen) {
  height: 100dvh;
  min-height: 0;
  overflow: hidden;
  padding: 10px;
  display: grid;
  grid-template-rows: auto auto minmax(0,1fr) auto;
  gap: 8px;
}
.reader-page:not(.reader-fullscreen) .reader-topbar {
  width: 100%;
  margin: 0;
  min-height: 52px;
  padding: 7px 10px;
}
.reader-top-actions { flex-wrap: nowrap; }
.top-page-button {
  min-height: 38px;
  padding: 0 12px;
  border: 1px solid #cbd9eb;
  border-radius: 11px;
  color: #244c7c;
  background: #edf3fb;
  font-weight: 850;
  cursor: pointer;
  white-space: nowrap;
}
.top-page-button.primary { color: white; border-color: #2e73ed; background: #2e73ed; }
.top-page-button:disabled { opacity: .38; cursor: not-allowed; }
.reader-page:not(.reader-fullscreen) .reading-toolbar {
  position: relative;
  z-index: 20;
  width: 100%;
  margin: 0;
  padding: 7px;
  display: grid;
  grid-template-columns: repeat(6, minmax(95px, auto)) minmax(180px,1fr) minmax(190px,1fr);
  gap: 6px;
  overflow-x: auto;
  border-radius: 14px;
}
.reader-page:not(.reader-fullscreen) .reading-toolbar .primary-button,
.reader-page:not(.reader-fullscreen) .reading-toolbar .secondary-button,
.reader-page:not(.reader-fullscreen) .reading-toolbar .ai-button {
  min-height: 38px;
  padding: 0 9px;
  font-size: 12px;
  white-space: nowrap;
}
.reader-page:not(.reader-fullscreen) .voice-control,
.reader-page:not(.reader-fullscreen) .speed-control {
  min-height: 38px;
  margin: 0;
  padding: 4px 8px;
  white-space: nowrap;
}
.reader-workspace {
  width: 100%;
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(0,2fr) minmax(300px,1fr);
  gap: 10px;
  overflow: hidden;
}
.reader-page:not(.reader-fullscreen) .reader-stage {
  width: 100%;
  height: 100%;
  min-height: 0;
  margin: 0;
  border-radius: 18px;
}
.reader-page:not(.reader-fullscreen) .reader-image-frame {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
}
.reader-page:not(.reader-fullscreen) .reader-image-frame .reader-image {
  width: auto;
  height: auto;
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}
.reader-side-panel {
  min-width: 0;
  min-height: 0;
  overflow-y: auto;
  padding: 10px;
  border: 1px solid #d8e2ef;
  border-radius: 18px;
  background: rgba(255,255,255,.96);
  box-shadow: 0 10px 28px rgba(42,69,106,.08);
}
.side-panel-title { position: sticky; top: 0; z-index: 2; display:flex; justify-content:space-between; padding: 5px 4px 9px; background: rgba(255,255,255,.96); color:#29496f; }
.reader-side-panel .reading-follow-panel,
.reader-side-panel .practice-panel,
.reader-side-panel .page-reading-scroll { width:100%; margin: 0 0 10px; box-shadow:none; }
.reader-side-panel .reading-follow-current { font-size: clamp(1rem,1.5vw,1.45rem); padding: 10px; }
.reader-side-panel .reading-follow-sentences { flex-direction: column; overflow-x: visible; max-height: 38vh; overflow-y: auto; }
.reader-side-panel .reading-follow-sentences button { flex: none; width:100%; }
.reader-side-empty { display:grid; place-items:center; min-height:180px; padding:20px; color:#64758b; text-align:center; }
.reader-page:not(.reader-fullscreen) > .reader-help,
.reader-page:not(.reader-fullscreen) > .analysis-error,
.reader-page:not(.reader-fullscreen) > .speech-notice { position: fixed; left: 50%; bottom: 12px; z-index: 50; transform: translateX(-50%); max-width: min(760px,90vw); margin:0; }
.reader-page:not(.reader-fullscreen) .reader-progress-track { width:100%; margin:0; height:5px; }
.reader-page:not(.reader-fullscreen) .reader-controls { display:none; }
.reader-fullscreen .reader-workspace { display:block; width:100vw; height:100dvh; }
.reader-fullscreen .reader-side-panel { display:none; }
.reader-fullscreen .reader-stage { width:100vw; height:100dvh; }

/* Deletion remains visible even for very long titles. */
.book-card { position: relative; }
.book-title-row { min-width:0; padding-right:64px; }
.book-title-row > div { min-width:0; }
.book-title-row h2 { overflow:hidden; text-overflow:ellipsis; white-space:nowrap; }
.book-title-row .icon-button.danger {
  position:absolute;
  top:12px;
  right:12px;
  z-index:5;
  min-width:46px;
  height:38px;
  padding:0 9px;
  box-shadow:0 5px 14px rgba(160,35,35,.14);
}

@media (max-width: 900px) {
  .reader-page:not(.reader-fullscreen) { overflow:auto; height:auto; min-height:100dvh; grid-template-rows:auto auto auto auto; }
  .reader-page:not(.reader-fullscreen) .reading-toolbar { grid-template-columns: repeat(4,minmax(110px,1fr)); overflow:visible; }
  .reader-workspace { grid-template-columns:1fr; overflow:visible; }
  .reader-page:not(.reader-fullscreen) .reader-stage { height:min(58dvh,620px); }
  .reader-side-panel { max-height:34dvh; }
  .reader-page:not(.reader-fullscreen) .reader-controls { display:none; }
}
@media (max-width: 600px) {
  .reader-page:not(.reader-fullscreen) { padding:6px; gap:6px; }
  .reader-topbar { grid-template-columns:auto minmax(0,1fr); }
  .reader-top-actions { grid-column:1 / -1; display:grid; grid-template-columns:1fr auto 1fr 1.25fr; width:100%; }
  .top-page-button,.fullscreen-button { min-height:38px; padding:0 7px; font-size:12px; }
  .reader-page:not(.reader-fullscreen) .reading-toolbar { grid-template-columns: repeat(3,minmax(100px,1fr)); gap:5px; }
  .reader-page:not(.reader-fullscreen) .voice-control,
  .reader-page:not(.reader-fullscreen) .speed-control { grid-column:span 3; }
  .reader-page:not(.reader-fullscreen) .reader-stage { height:48dvh; min-height:300px; }
  .reader-side-panel { max-height:30dvh; padding:7px; }
}

/* v3.1: keep every reader control inside the viewport and support iPhone photo preparation */
.image-prepare-status {
  margin: 14px 0 0;
  padding: 10px 12px;
  border-radius: 12px;
  color: #24548e;
  background: #edf5ff;
  font-size: 13px;
  font-weight: 800;
  text-align: center;
}

.reader-page:not(.reader-fullscreen) {
  grid-template-areas:
    "topbar"
    "toolbar"
    "workspace"
    "progress";
  grid-template-rows: auto auto minmax(0, 1fr) 5px;
  height: 100dvh;
  min-height: 0;
  overflow: hidden;
}
.reader-page:not(.reader-fullscreen) > .reader-topbar { grid-area: topbar; }
.reader-page:not(.reader-fullscreen) > .reading-toolbar { grid-area: toolbar; }
.reader-page:not(.reader-fullscreen) > .reader-workspace { grid-area: workspace; }
.reader-page:not(.reader-fullscreen) > .reader-progress-track { grid-area: progress; }

.reader-page:not(.reader-fullscreen) .reading-toolbar {
  grid-template-columns: repeat(8, minmax(0, 1fr));
  align-items: stretch;
  overflow: visible;
}
.reader-page:not(.reader-fullscreen) .reading-toolbar > button {
  min-width: 0;
  width: 100%;
  line-height: 1.15;
  white-space: normal;
}
.reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control,
.reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control {
  grid-column: span 4;
  min-width: 0;
}
.reader-page:not(.reader-fullscreen) .voice-control select,
.reader-page:not(.reader-fullscreen) .speed-control input { min-width: 0; }

.reader-page:not(.reader-fullscreen) > .reader-help,
.reader-page:not(.reader-fullscreen) > .analysis-error,
.reader-page:not(.reader-fullscreen) > .speech-notice {
  top: 142px;
  bottom: auto;
  pointer-events: none;
}

@media (max-width: 1100px) {
  .reader-page:not(.reader-fullscreen) .reading-toolbar {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control {
    grid-column: span 2;
  }
  .reader-page:not(.reader-fullscreen) > .reader-help,
  .reader-page:not(.reader-fullscreen) > .analysis-error,
  .reader-page:not(.reader-fullscreen) > .speech-notice { top: 184px; }
}

@media (max-width: 900px) {
  .reader-page:not(.reader-fullscreen) {
    height: 100dvh;
    min-height: 0;
    overflow: hidden;
    grid-template-rows: auto auto minmax(0, 1fr) 5px;
  }
  .reader-workspace {
    grid-template-columns: minmax(0, 1.45fr) minmax(250px, .75fr);
    overflow: hidden;
  }
  .reader-page:not(.reader-fullscreen) .reader-stage {
    width: 100%;
    height: 100%;
    min-height: 0;
  }
  .reader-side-panel {
    max-height: none;
    min-height: 0;
  }
}

@media (max-width: 720px) {
  .reader-page:not(.reader-fullscreen) {
    padding: 6px;
    gap: 5px;
  }
  .reader-page:not(.reader-fullscreen) .reader-topbar {
    min-height: 44px;
    padding: 5px 7px;
  }
  .reader-workspace {
    grid-template-columns: 1fr;
    grid-template-rows: minmax(0, 1.7fr) minmax(118px, .65fr);
    gap: 6px;
  }
  .reader-side-panel {
    max-height: none;
    padding: 6px;
    border-radius: 13px;
  }
  .reader-page:not(.reader-fullscreen) .reading-toolbar {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 4px;
    padding: 5px;
  }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .primary-button,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .secondary-button,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .ai-button {
    min-height: 35px;
    padding: 3px 5px;
    font-size: 10.5px;
  }
  .reader-page:not(.reader-fullscreen) .voice-control,
  .reader-page:not(.reader-fullscreen) .speed-control {
    min-height: 34px;
    padding: 2px 5px;
    font-size: 11px;
  }
  .reader-page:not(.reader-fullscreen) > .reader-help,
  .reader-page:not(.reader-fullscreen) > .analysis-error,
  .reader-page:not(.reader-fullscreen) > .speech-notice { top: 174px; }
}

@media (max-width: 430px) {
  .reader-page:not(.reader-fullscreen) .reading-toolbar {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control {
    grid-column: span 2;
  }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .primary-button,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .secondary-button,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .ai-button {
    min-height: 32px;
    font-size: 10px;
  }
  .reader-workspace {
    grid-template-rows: minmax(0, 1.55fr) minmax(105px, .55fr);
  }
  .reader-page:not(.reader-fullscreen) > .reader-help,
  .reader-page:not(.reader-fullscreen) > .analysis-error,
  .reader-page:not(.reader-fullscreen) > .speech-notice { top: 250px; }
}

/* v3.2: expressive story narration without adding any OCR work */
.narration-control {
  display: grid;
  grid-template-columns: auto minmax(120px, 210px);
  align-items: center;
  gap: 8px;
  color: #455d7a;
  font-size: 13px;
  font-weight: 800;
}
.narration-control select {
  min-height: 40px;
  min-width: 0;
  padding: 0 34px 0 11px;
  border: 1px solid #cbd8e8;
  border-radius: 11px;
  color: #234567;
  background: #f8fbff;
  font: inherit;
  cursor: pointer;
}
.reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control { grid-column: span 3; }
.reader-page:not(.reader-fullscreen) .reading-toolbar .narration-control { grid-column: span 2; min-width: 0; }
.reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control { grid-column: span 3; }
.reader-page:not(.reader-fullscreen) .narration-control { min-height: 38px; margin: 0; padding: 4px 8px; white-space: nowrap; }

@media (max-width: 1100px) {
  .reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .narration-control { grid-column: span 2; }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control { grid-column: span 4; }
}

@media (max-width: 720px) {
  .narration-control { width: 100%; grid-template-columns: auto 1fr; }
  .narration-control select { width: 100%; }
  .reader-page:not(.reader-fullscreen) .voice-control,
  .reader-page:not(.reader-fullscreen) .narration-control,
  .reader-page:not(.reader-fullscreen) .speed-control {
    min-height: 34px;
    padding: 2px 5px;
    font-size: 11px;
  }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .narration-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control { grid-column: span 2; }
}

@media (max-width: 430px) {
  .reader-page:not(.reader-fullscreen) .reading-toolbar .voice-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .narration-control,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .speed-control { grid-column: span 2; }
}


/* v3.3: compact non-blocking speech notice and Gemini TTS quota cooldown */
.reader-page:not(.reader-fullscreen) > .speech-notice {
  position: fixed;
  top: auto !important;
  left: auto !important;
  right: max(12px, env(safe-area-inset-right));
  bottom: max(12px, env(safe-area-inset-bottom));
  z-index: 80;
  width: min(390px, calc(100vw - 24px));
  max-width: none;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 9px;
  margin: 0;
  padding: 10px 10px 10px 12px;
  transform: none !important;
  border: 1px solid #c9dcfa;
  border-radius: 14px;
  color: #28558d;
  background: rgba(238,245,255,.97);
  text-align: left;
  font-size: 12.5px;
  line-height: 1.4;
  font-weight: 750;
  box-shadow: 0 12px 30px rgba(37,76,126,.2);
  pointer-events: auto !important;
  backdrop-filter: blur(10px);
}
.speech-notice-icon { font-size: 15px; }
.speech-notice-text { min-width: 0; }
.speech-notice-close {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 9px;
  color: #315b8f;
  background: rgba(255,255,255,.72);
  font-size: 20px;
  line-height: 1;
  cursor: pointer;
}
.speech-notice-close:hover { background: white; }
@media (max-width: 600px) {
  .reader-page:not(.reader-fullscreen) > .speech-notice {
    right: max(8px, env(safe-area-inset-right));
    bottom: max(8px, env(safe-area-inset-bottom));
    width: calc(100vw - 16px);
    font-size: 12px;
  }
}

/* v3.4: backup transfer, wider speed range, visible sentence pauses and no blocking help banner */
.library-heading-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}
.library-backup-button {
  min-height: 38px;
  padding: 0 12px;
  border: 1px solid #cbd8e8;
  border-radius: 11px;
  color: #315579;
  background: #f7faff;
  font-size: 12px;
  font-weight: 850;
  cursor: pointer;
}
.library-backup-button:hover { background: #eaf3ff; }
.library-backup-button:disabled { cursor: wait; opacity: .55; }
.backup-status {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
  padding: 11px 13px;
  border: 1px solid #cce0f8;
  border-radius: 13px;
  color: #28558d;
  background: #eef6ff;
  font-size: 13px;
  font-weight: 750;
}
.backup-status p { margin: 0; }
.backup-status button {
  width: 30px;
  height: 30px;
  padding: 0;
  border: 0;
  border-radius: 9px;
  color: #315b8f;
  background: white;
  font-size: 20px;
  cursor: pointer;
}
.empty-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 9px; }
.book-title-row { padding-right: 122px; }
.book-card-actions {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 5;
  display: flex;
  gap: 6px;
}
.book-title-row .book-card-actions .icon-button {
  position: static;
  min-width: 50px;
  height: 36px;
  padding: 0 8px;
  box-shadow: 0 5px 14px rgba(35,72,120,.1);
}
.book-title-row .book-card-actions .icon-button.export { color: #245a9c; background: #eaf3ff; }
.book-title-row .book-card-actions .icon-button.export:hover { background: #dbeaff; }
.book-title-row .book-card-actions .icon-button.danger { color: #9f2f2a; background: #fff1ef; }

/* The old translucent touch instruction was fixed over the controls. It is now removed. */
.reader-page:not(.reader-fullscreen) > .reader-help { display: none !important; }
.speed-control span { min-width: 52px; }

@media (max-width: 760px) {
  .section-heading { align-items: flex-start; gap: 12px; }
  .library-heading-actions { max-width: 230px; }
  .library-backup-button { min-height: 35px; padding: 0 9px; font-size: 11px; }
  .book-title-row { padding-right: 112px; }
  .book-card-actions { top: 9px; right: 9px; gap: 4px; }
  .book-title-row .book-card-actions .icon-button { min-width: 48px; height: 34px; font-size: 11px; }
}

@media (max-width: 430px) {
  .section-heading { display: grid; grid-template-columns: 1fr; }
  .library-heading-actions { max-width: none; justify-content: flex-start; }
  .book-title-row { padding-right: 104px; }
  .book-title-row .book-card-actions .icon-button { min-width: 45px; padding: 0 6px; font-size: 10.5px; }
}

/* v3.5: direct page jump, reference-audio narration and local completion games */
.reader-top-actions {
  flex-wrap: wrap;
}
.page-jump-control select,
.reader-bottom-page-select select,
.fullscreen-page-jump select {
  min-height: 38px;
  padding: 0 29px 0 10px;
  border: 1px solid #cbd8e8;
  border-radius: 11px;
  color: #234567;
  background: #f8fbff;
  font: inherit;
  font-weight: 850;
  cursor: pointer;
}
.page-jump-control select { min-width: 82px; }
.first-page-button { white-space: nowrap; }
.read-page-count {
  min-width: 0;
  display: grid;
  place-items: center;
  min-height: 38px;
  padding: 0 9px;
  border: 1px solid #d5e2f1;
  border-radius: 11px;
  color: #315579;
  background: #f5f9ff;
  font-size: 12px;
  font-weight: 900;
  white-space: nowrap;
}
.quiz-launch-button {
  min-height: 42px;
  padding: 0 14px;
  border: 0;
  border-radius: 13px;
  color: #58340a;
  background: linear-gradient(135deg, #ffe17a, #ffb854);
  font-weight: 950;
  box-shadow: 0 8px 18px rgba(190,115,0,.18);
  cursor: pointer;
}
.quiz-launch-button:disabled { cursor: not-allowed; opacity: .48; }
.reader-page:not(.reader-fullscreen) .reading-toolbar .quiz-launch-button {
  min-width: 0;
  width: 100%;
  line-height: 1.15;
}
.reader-bottom-page-select {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid #d5e2f1;
  border-radius: 13px;
  color: #315579;
  background: white;
  font-size: 13px;
  font-weight: 850;
}
.reader-bottom-page-select select { min-width: 62px; }
.reader-controls { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.fullscreen-page-jump {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-top: 3px;
  font-size: 11px;
  font-weight: 800;
  opacity: .96;
}
.fullscreen-page-jump select {
  min-height: 28px;
  padding: 0 23px 0 8px;
  border-color: rgba(255,255,255,.35);
  color: white;
  background: rgba(14,27,45,.78);
  font-size: 12px;
}

/* Completion quiz */
.completion-quiz-backdrop {
  position: fixed;
  inset: 0;
  z-index: 12000;
  display: grid;
  place-items: center;
  padding: max(16px, env(safe-area-inset-top)) max(16px, env(safe-area-inset-right)) max(16px, env(safe-area-inset-bottom)) max(16px, env(safe-area-inset-left));
  background: rgba(8,25,50,.72);
  backdrop-filter: blur(12px);
}
.completion-quiz-card {
  position: relative;
  width: min(760px, 100%);
  max-height: min(860px, 94dvh);
  overflow-y: auto;
  padding: clamp(22px, 5vw, 46px);
  border: 1px solid rgba(255,255,255,.72);
  border-radius: 30px;
  background:
    radial-gradient(circle at 8% 3%, rgba(255,226,112,.42), transparent 26%),
    radial-gradient(circle at 96% 8%, rgba(112,187,255,.32), transparent 28%),
    #fff;
  box-shadow: 0 28px 85px rgba(0,0,0,.34);
  text-align: center;
}
.completion-quiz-close {
  position: absolute;
  top: 13px;
  right: 13px;
  z-index: 2;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 50%;
  color: #45627f;
  background: #eef4fb;
  font-size: 26px;
  cursor: pointer;
}
.completion-trophy { font-size: clamp(56px, 12vw, 92px); line-height: 1; filter: drop-shadow(0 10px 12px rgba(121,83,0,.16)); }
.completion-confetti { margin-bottom: 10px; font-size: clamp(24px, 5vw, 38px); letter-spacing: .2em; }
.completion-quiz-start h2,
.completion-quiz-finish h2,
.completion-quiz-empty h2,
.completion-question h2 { margin: 8px 0 12px; color: #163b69; }
.completion-quiz-start > p:not(.eyebrow),
.completion-quiz-finish > p,
.completion-quiz-empty > p { color: #60738a; line-height: 1.65; }
.completion-best-score {
  width: fit-content;
  margin: 18px auto;
  padding: 9px 14px;
  border-radius: 999px;
  color: #8a5700;
  background: #fff4c6;
  font-weight: 900;
}
.completion-start-button { min-width: 210px; min-height: 52px; font-size: 17px; }
.completion-question { text-align: left; }
.completion-question-header { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; color: #41617f; font-weight: 900; }
.completion-question-progress { flex: 1; height: 9px; overflow: hidden; border-radius: 999px; background: #e7eef7; }
.completion-question-progress i { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg, #397df4, #69b5ff); }
.completion-question .eyebrow { margin-bottom: 7px; }
.completion-question h2 { font-size: clamp(20px, 3.5vw, 29px); line-height: 1.42; }
.completion-options { display: grid; gap: 10px; margin-top: 22px; }
.completion-option {
  width: 100%;
  min-height: 60px;
  display: grid;
  grid-template-columns: 38px minmax(0,1fr);
  align-items: center;
  gap: 11px;
  padding: 10px 14px;
  border: 2px solid #dce6f2;
  border-radius: 16px;
  color: #294866;
  background: #fbfdff;
  text-align: left;
  cursor: pointer;
  transition: transform .14s ease, border-color .14s ease, background .14s ease;
}
.completion-option:hover:not(:disabled) { transform: translateY(-2px); border-color: #8db8f4; background: #f0f7ff; }
.completion-option > span { width: 34px; height: 34px; display: grid; place-items: center; border-radius: 11px; color: #2862aa; background: #e7f1ff; font-weight: 950; }
.completion-option > strong { min-width: 0; font-size: 15px; line-height: 1.45; }
.completion-option.correct { border-color: #45a878; background: #eafaf2; }
.completion-option.correct > span { color: white; background: #38a16e; }
.completion-option.wrong { border-color: #db6c67; background: #fff0ef; }
.completion-option.wrong > span { color: white; background: #d85d57; }
.completion-answer { margin-top: 17px; padding: 15px; border-radius: 16px; text-align: left; }
.completion-answer.correct { color: #18643f; background: #eaf9f1; }
.completion-answer.wrong { color: #8c3430; background: #fff0ef; }
.completion-answer p { margin: 5px 0 13px; line-height: 1.5; }
.completion-answer .primary-button { width: 100%; }
.completion-stars { font-size: clamp(42px, 9vw, 72px); letter-spacing: .08em; }
.completion-score { font-size: 21px; }
.completion-score strong { color: #246ae3; font-size: 44px; }
.completion-quiz-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 10px; margin-top: 22px; }

@media (max-width: 900px) {
  .reader-top-actions { gap: 5px; }
  .reader-top-actions .top-page-button,
  .reader-top-actions .fullscreen-button { padding-inline: 8px; }
}
@media (max-width: 720px) {
  .reader-top-actions {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: repeat(3, minmax(0,1fr));
    width: 100%;
  }
  .reader-top-actions > * { min-width: 0; width: 100%; }
  .page-jump-control select { width: 100%; min-width: 0; }
  .reader-progress-pill { display: grid; place-items: center; }
  .reader-page:not(.reader-fullscreen) .reading-toolbar .quiz-launch-button,
  .reader-page:not(.reader-fullscreen) .reading-toolbar .read-page-count { grid-column: span 2; }
  .completion-quiz-card { padding: 28px 16px 20px; border-radius: 22px; }
  .completion-option { grid-template-columns: 34px minmax(0,1fr); min-height: 55px; padding: 8px 10px; }
  .completion-option > strong { font-size: 13.5px; }
}
@media (max-width: 430px) {
  .reader-top-actions { grid-template-columns: repeat(3, minmax(0,1fr)); }
  .reader-top-actions .top-page-button,
  .reader-top-actions .fullscreen-button,
  .page-jump-control select { min-height: 34px; font-size: 10.5px; }
  .completion-quiz-backdrop { padding: 8px; }
  .completion-quiz-card { max-height: 96dvh; }
  .completion-question h2 { font-size: 18px; }
}

/* v3.6.2: force the complete original photo into the visible study area. */
.reader-page:not(.reader-fullscreen) .reader-stage {
  position: relative;
  min-width: 0;
  min-height: 0;
  overflow: hidden;
  padding: 0;
}
.reader-image-fit-area {
  position: absolute;
  inset: 6px;
  min-width: 0;
  min-height: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  box-sizing: border-box;
}
.reader-image-fit-area .reader-image-frame {
  position: relative;
  flex: 0 0 auto;
  display: block;
  max-width: 100%;
  max-height: 100%;
  overflow: hidden;
  line-height: 0;
  box-sizing: border-box;
}
.reader-image-fit-area .reader-image-frame .reader-image {
  display: block;
  width: 100%;
  height: 100%;
  max-width: none;
  max-height: none;
  object-fit: contain;
  object-position: center;
}
.reader-image-fit-area .coordinate-overlay { position: absolute; inset: 0; }
.reader-fullscreen .reader-image-fit-area {
  position: absolute;
  inset: 0;
  width: auto;
  height: auto;
  background: #05090f;
}