:root {
  color-scheme: light;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #dfe9df;
  color: #183128;
  --topbar-height: 3.75rem;
  --controls-height: 4.5rem;
  --touch-target: 44px;
  --surface: #ffffff;
  --paper: #fffdf7;
  --accent: #1f6b4d;
  --accent-dark: #164b38;
  --border: #cddbd2;
  --shadow: 0 1rem 2.5rem rgb(21 68 49 / 18%);
}

* {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  min-height: 100%;
  margin: 0;
  overflow-x: hidden;
}

body {
  min-height: 100dvh;
  background:
    radial-gradient(circle at 50% 12%, rgb(255 255 255 / 72%), transparent 38rem),
    #dfe9df;
}

button,
input,
select {
  min-height: var(--touch-target);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  background: var(--surface);
  color: inherit;
  font: inherit;
}

button {
  cursor: pointer;
}

button:disabled,
input:disabled,
select:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

button:focus-visible,
input:focus-visible,
select:focus-visible,
#viewer:focus-visible {
  outline: 3px solid rgb(37 99 235 / 45%);
  outline-offset: 2px;
}

.topbar {
  position: fixed;
  z-index: 20;
  inset: 0 0 auto;
  height: calc(var(--topbar-height) + env(safe-area-inset-top));
  padding: env(safe-area-inset-top) 0 0;
  padding-left: max(0.75rem, env(safe-area-inset-left));
  padding-right: max(0.75rem, env(safe-area-inset-right));
  display: grid;
  grid-template-columns: var(--touch-target) minmax(0, 1fr) minmax(var(--touch-target), auto);
  align-items: center;
  gap: 0.5rem;
  border-bottom: 1px solid rgb(255 255 255 / 18%);
  background: rgb(31 107 77 / 96%);
  color: #ffffff;
  backdrop-filter: blur(12px);
}

.topbar h1 {
  margin: 0;
  overflow: hidden;
  font-size: 1.05rem;
  text-align: center;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.icon-button {
  display: grid;
  place-items: center;
  width: var(--touch-target);
  min-width: var(--touch-target);
  padding: 0;
  border-color: transparent;
  background: transparent;
  color: inherit;
  font-size: 1.35rem;
}

#viewer {
  width: 100%;
  height: 100dvh;
  min-width: 0;
  padding: calc(var(--topbar-height) + env(safe-area-inset-top) + 1rem) 0
    calc(var(--controls-height) + env(safe-area-inset-bottom) + 1rem);
  padding-left: max(0.75rem, env(safe-area-inset-left));
  padding-right: max(0.75rem, env(safe-area-inset-right));
  display: grid;
  place-items: center;
  overflow: hidden;
  touch-action: none;
}

#pageStage {
  position: relative;
  width: min(
    100%,
    52rem,
    calc((100dvh - var(--topbar-height) - var(--controls-height) - env(safe-area-inset-top) - env(safe-area-inset-bottom) - 2rem) * 1323 / 1871)
  );
  max-width: 100%;
  aspect-ratio: 1323 / 1871;
  overflow: hidden;
  touch-action: none;
  border: 1px solid rgb(89 105 93 / 18%);
  border-radius: 0.9rem;
  background: var(--paper);
  box-shadow: var(--shadow);
  transform: translate3d(0, 0, 0) scale(1);
  transform-origin: center;
  will-change: transform;
}

.zoom-reset {
  position: fixed;
  z-index: 5;
  left: 50%;
  bottom: calc(var(--controls-height) + env(safe-area-inset-bottom) + 0.5rem);
  transform: translateX(-50%);
  border: 0;
  border-radius: 999px;
  padding: 0.55rem 0.9rem;
  background: rgb(20 48 36 / 86%);
  color: white;
  box-shadow: var(--shadow);
}

#pageImage {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  user-select: none;
  -webkit-user-drag: none;
}

#wordOverlay {
  position: absolute;
  z-index: 1;
  inset: 0;
  pointer-events: none;
}

.word-target {
  position: absolute;
  min-height: 0;
  padding: 0;
  border: 0;
  border-radius: 0.2rem;
  background: transparent;
  color: transparent;
  pointer-events: auto;
  touch-action: none;
  -webkit-touch-callout: none;
}

.word-target:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
  background: rgb(37 99 235 / 14%);
}

.word-target.speaking {
  background: rgb(250 204 21 / 38%);
  box-shadow: 0 0 0 2px rgb(245 158 11 / 72%);
}

.status-panel {
  position: absolute;
  z-index: 2;
  inset: 0;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 0.75rem;
  padding: 1.5rem;
  background: rgb(255 253 247 / 94%);
  text-align: center;
}

.status-panel[hidden],
.toast[hidden],
.drawer-backdrop[hidden] {
  display: none;
}

.spinner {
  width: 2rem;
  height: 2rem;
  border: 3px solid #dbe5f5;
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(1turn);
  }
}

.drawer-backdrop {
  position: fixed;
  z-index: 30;
  inset: 0;
  background: rgb(15 23 42 / 48%);
}

.drawer {
  position: fixed;
  z-index: 40;
  inset: 0 auto 0 0;
  width: min(84vw, 360px);
  max-width: 100%;
  padding: max(1rem, env(safe-area-inset-top)) 0 max(1rem, env(safe-area-inset-bottom));
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
  overflow-y: auto;
  overscroll-behavior: contain;
  background: var(--surface);
  box-shadow: var(--shadow);
  transform: translateX(-105%);
  transition: transform 180ms ease;
}

.drawer[aria-hidden="false"] {
  transform: translateX(0);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.drawer-header h2 {
  margin: 0;
  font-size: 1.2rem;
}

.chapter-list {
  margin: 1rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.5rem;
  list-style: none;
}

.chapter-link {
  width: 100%;
  min-height: var(--touch-target);
  padding: 0.7rem 0.85rem;
  border-color: transparent;
  background: #edf5f0;
  text-align: left;
}

.chapter-link:hover {
  background: #dcece2;
}

.page-controls {
  position: fixed;
  z-index: 20;
  inset: auto 0 0;
  min-height: calc(var(--controls-height) + env(safe-area-inset-bottom));
  padding: 0.65rem 0 calc(0.65rem + env(safe-area-inset-bottom));
  padding-left: max(0.75rem, env(safe-area-inset-left));
  padding-right: max(0.75rem, env(safe-area-inset-right));
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: safe center;
  gap: 0.45rem;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  border-top: 1px solid var(--border);
  background: rgb(255 253 247 / 96%);
  backdrop-filter: blur(12px);
}

.page-controls button {
  flex: 0 0 auto;
  padding-inline: 0.8rem;
}

.page-indicator {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 0.3rem;
  white-space: nowrap;
}

#pageInput {
  width: 3.25rem;
  padding: 0.4rem;
  text-align: center;
}

#rateSelect {
  flex: 0 0 auto;
  padding-inline: 0.4rem;
}

.toast {
  position: fixed;
  z-index: 50;
  left: 50%;
  bottom: calc(var(--controls-height) + env(safe-area-inset-bottom) + 1rem);
  max-width: min(90vw, 26rem);
  padding: 0.75rem 1rem;
  border-radius: 0.75rem;
  background: #172033;
  color: #ffffff;
  box-shadow: var(--shadow);
  text-align: center;
  transform: translateX(-50%);
}

.voice-button-label {
  max-width: 7rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-size: 0.72rem;
}

.voice-dialog {
  width: min(90vw, 28rem);
  padding: 0;
  border: 0;
  border-radius: 1rem;
  color: var(--ink, #172033);
}

.voice-dialog::backdrop { background: rgb(15 23 42 / 55%); }
.voice-dialog-card { padding: 1rem; }
.voice-dialog-header { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.voice-dialog-header h2 { margin: 0; font-size: 1.1rem; }
.voice-list { display: grid; gap: 0.5rem; margin-top: 1rem; }
.voice-option { width: 100%; padding: 0.75rem; text-align: left; }
.voice-option[aria-pressed="true"] { outline: 3px solid #2563eb; }

.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;
}

@media (max-width: 24rem) {
  .voice-button-label {
    display: none;
  }

  .page-controls {
    gap: 0.3rem;
    padding-left: max(0.35rem, env(safe-area-inset-left));
    padding-right: max(0.35rem, env(safe-area-inset-right));
  }

  .page-controls button {
    padding-inline: 0.55rem;
    font-size: 0.875rem;
  }
}

@media (min-width: 48rem) and (orientation: landscape) {
  #viewer {
    padding-left: max(2rem, env(safe-area-inset-left));
    padding-right: max(2rem, env(safe-area-inset-right));
  }

  #pageStage {
    border-radius: 1rem;
  }

  .page-controls {
    gap: 0.75rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}