:root {
  color-scheme: light;
  --paper: #fffaf3;
  --paper-soft: #f6eadc;
  --champagne: #cfad78;
  --champagne-deep: #a07a49;
  --tea: #d9c1a7;
  --sage: #7d8b78;
  --ink: #5c4a3a;
  --shadow: rgba(75, 52, 32, 0.24);
  --page-width: min(96vw, 430px);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100svh;
  min-height: 100dvh;
  overflow: hidden;
  font-family: "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", ui-sans-serif, system-ui, sans-serif;
  color: var(--ink);
  background:
    linear-gradient(145deg, rgba(255, 250, 243, 0.98) 0%, rgba(244, 230, 212, 0.98) 48%, rgba(216, 192, 157, 0.96) 100%),
    #f6eadc;
}

button {
  font: inherit;
}

.app {
  width: min(100%, 980px);
  height: 100vh;
  height: 100svh;
  height: 100dvh;
  margin: 0 auto;
  padding:
    max(10px, env(safe-area-inset-top))
    max(12px, env(safe-area-inset-right))
    max(10px, env(safe-area-inset-bottom))
    max(12px, env(safe-area-inset-left));
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  gap: 10px;
}

.topbar,
.toolbar {
  width: min(100%, 520px);
  margin: 0 auto;
  border: 1px solid rgba(160, 122, 73, 0.26);
  background: rgba(255, 250, 243, 0.74);
  box-shadow: 0 10px 30px rgba(122, 88, 53, 0.12);
  backdrop-filter: blur(14px);
}

.topbar {
  min-height: 46px;
  padding: 8px 12px;
  border-radius: 999px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand {
  margin: 0;
  min-width: 0;
  overflow: hidden;
  color: var(--champagne-deep);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1rem;
  line-height: 1.1;
  white-space: nowrap;
  text-overflow: ellipsis;
}

.page-counter {
  flex: 0 0 auto;
  min-width: 64px;
  padding: 6px 10px;
  border-radius: 999px;
  color: #fffaf3;
  background: linear-gradient(135deg, var(--champagne-deep), var(--champagne));
  font-size: 0.82rem;
  font-weight: 700;
  text-align: center;
}

.stage {
  position: relative;
  min-height: 0;
  display: grid;
  place-items: center;
}

.book-frame {
  position: relative;
  width: var(--page-width);
  aspect-ratio: 941 / 1672;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.75);
  border-radius: 18px;
  background: var(--paper);
  box-shadow:
    0 24px 55px var(--shadow),
    0 2px 0 rgba(255, 255, 255, 0.86) inset;
  touch-action: none;
  user-select: none;
}

.book-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  border-radius: inherit;
  box-shadow: 0 0 0 1px rgba(160, 122, 73, 0.16) inset;
}

.page-track {
  height: 100%;
  display: flex;
  transition: transform 520ms cubic-bezier(0.22, 0.88, 0.26, 1);
  will-change: transform;
}

.book-frame.is-dragging .page-track,
.book-frame.is-instant .page-track {
  transition: none;
}

.page {
  position: relative;
  min-width: 100%;
  height: 100%;
  overflow: hidden;
  background: var(--paper);
}

.zoom-layer {
  position: absolute;
  inset: 0;
  transform: translate3d(0, 0, 0) scale(1);
  transform-origin: 0 0;
  will-change: transform;
}

.zoom-layer.is-animating {
  transition: transform 220ms ease;
}

.book-frame.is-zoomed {
  cursor: grab;
}

.book-frame.is-panning {
  cursor: grabbing;
}

.zoom-controls {
  position: absolute;
  z-index: 8;
  top: 8px;
  right: 8px;
  min-height: 36px;
  padding: 3px;
  border: 1px solid rgba(160, 122, 73, 0.28);
  border-radius: 10px;
  display: flex;
  align-items: center;
  gap: 2px;
  color: var(--champagne-deep);
  background: rgba(255, 250, 243, 0.94);
  box-shadow: 0 8px 22px rgba(93, 67, 41, 0.18);
  backdrop-filter: blur(10px);
  cursor: default;
}

.zoom-controls button {
  width: 29px;
  height: 28px;
  border: 0;
  border-radius: 7px;
  display: grid;
  place-items: center;
  color: var(--champagne-deep);
  background: rgba(207, 173, 120, 0.18);
  font-weight: 850;
  line-height: 1;
  cursor: pointer;
}

.zoom-controls button:hover:not(:disabled),
.zoom-controls button:focus-visible {
  outline: none;
  color: var(--paper);
  background: var(--champagne-deep);
}

.zoom-controls button:disabled {
  opacity: 0.34;
  cursor: default;
}

.zoom-controls output {
  min-width: 48px;
  padding: 0 3px;
  font: 800 0.68rem ui-monospace, "SFMono-Regular", Consolas, monospace;
  text-align: center;
}

.zoom-controls .zoom-reset {
  margin-left: 2px;
  color: var(--paper);
  background: var(--champagne-deep);
}

.page img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
  pointer-events: none;
  -webkit-user-drag: none;
}

.hotspot {
  position: absolute;
  z-index: 3;
  border: 0;
  border-radius: 10px;
  padding: 0;
  background: rgba(255, 255, 255, 0);
  cursor: pointer;
}

.hotspot:focus-visible {
  outline: 2px solid rgba(160, 122, 73, 0.74);
  outline-offset: 2px;
  background: rgba(255, 250, 243, 0.18);
}

.side-arrow {
  position: absolute;
  z-index: 5;
  top: 50%;
  width: 46px;
  height: 46px;
  border: 1px solid rgba(160, 122, 73, 0.28);
  border-radius: 999px;
  display: grid;
  place-items: center;
  color: var(--champagne-deep);
  background: rgba(255, 250, 243, 0.82);
  box-shadow: 0 12px 26px rgba(93, 67, 41, 0.18);
  cursor: pointer;
  transform: translateY(-50%);
  transition: transform 160ms ease, opacity 160ms ease, background 160ms ease;
}

.side-arrow span {
  display: block;
  margin-top: -3px;
  font-size: 2.1rem;
  line-height: 1;
}

.side-arrow:hover,
.side-arrow:focus-visible {
  outline: none;
  background: rgba(255, 255, 255, 0.96);
  transform: translateY(-50%) scale(1.04);
}

.side-arrow:disabled,
.toolbar-button:disabled {
  cursor: default;
  opacity: 0.36;
}

.side-arrow-prev {
  left: clamp(12px, 5vw, 72px);
}

.side-arrow-next {
  right: clamp(12px, 5vw, 72px);
}

.toolbar {
  padding: 6px;
  border-radius: 18px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 6px;
}

.toolbar-button {
  min-width: 0;
  min-height: 42px;
  border: 0;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  color: var(--ink);
  background: transparent;
  font-size: 0.9rem;
  font-weight: 700;
  white-space: nowrap;
  cursor: pointer;
  transition: background 160ms ease, transform 160ms ease;
}

.toolbar-button span {
  min-width: 0;
}

.toolbar-button:hover,
.toolbar-button:focus-visible {
  outline: none;
  background: rgba(207, 173, 120, 0.18);
}

.toolbar-button:active {
  transform: translateY(1px);
}

.toolbar-button-primary {
  color: #fffaf3;
  background: linear-gradient(135deg, var(--champagne-deep), var(--champagne));
  box-shadow: 0 8px 18px rgba(160, 122, 73, 0.2);
}

.toolbar-button-primary:hover,
.toolbar-button-primary:focus-visible {
  background: linear-gradient(135deg, #8f6d40, #cba66d);
}

.noscript {
  position: fixed;
  inset: auto 12px 12px;
  margin: 0;
  padding: 10px 12px;
  border-radius: 8px;
  color: #fffaf3;
  background: #5c4a3a;
  font-size: 0.9rem;
  text-align: center;
}

@media (max-width: 720px) {
  .app {
    width: 100%;
    padding:
      max(6px, env(safe-area-inset-top))
      max(4px, env(safe-area-inset-right))
      max(6px, env(safe-area-inset-bottom))
      max(4px, env(safe-area-inset-left));
    grid-template-rows: auto auto auto;
    align-content: start;
    gap: 4px;
  }

  .stage {
    min-height: auto;
  }

  .topbar {
    width: 100%;
    min-height: 38px;
    padding: 6px 10px;
  }

  .brand {
    font-size: 0.94rem;
  }

  .page-counter {
    min-width: 58px;
    padding: 5px 9px;
    font-size: 0.78rem;
  }

  .side-arrow {
    display: none;
  }

  .zoom-controls {
    display: none;
  }

  .book-frame {
    border-radius: 12px;
  }

  .toolbar {
    width: 100%;
    padding: 4px;
    border-radius: 14px;
    gap: 4px;
  }

  .toolbar-button {
    min-height: 38px;
    border-radius: 10px;
    font-size: 0.82rem;
  }
}

@media (max-width: 340px) {
  .toolbar-button {
    gap: 4px;
    font-size: 0.78rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-track,
  .zoom-layer,
  .side-arrow,
  .toolbar-button {
    transition: none;
  }
}