:root {
  color-scheme: dark;
  --ink: #211d19;
  --paper: #eee5d2;
  --paper-deep: #d8c9ac;
  --wood: #29241f;
  --wood-light: #3c342d;
  --cream: #f5eddf;
  --muted: #b8aa99;
  --terracotta: #a9553f;
  --sage: #72806b;
  --page-duration: 700ms;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  min-width: 320px;
  overflow-x: hidden;
  background:
    radial-gradient(circle at 50% -20%, rgba(255, 245, 221, 0.12), transparent 45%),
    linear-gradient(145deg, #211d19, var(--wood) 54%, #171411);
  color: var(--cream);
  font-family: "Courier New", Courier, monospace;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  font: inherit;
}

.book-app {
  min-height: 100svh;
  display: grid;
  grid-template-rows: auto 1fr auto;
  align-items: center;
  gap: clamp(1rem, 2.6vh, 1.75rem);
  padding: clamp(1rem, 2.5vw, 2rem);
}

.book-header {
  width: min(100%, 1280px);
  margin-inline: auto;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 1rem;
}

.wordmark {
  width: max-content;
  color: inherit;
  text-decoration: none;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.wordmark__title,
.wordmark__subtitle {
  display: block;
}

.wordmark__title {
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1rem, 1.8vw, 1.3rem);
  letter-spacing: 0.04em;
  text-transform: none;
}

.wordmark__subtitle {
  margin-top: 0.2rem;
  color: var(--muted);
  font-size: 0.62rem;
}

.book-header__hint {
  margin: 0;
  color: var(--muted);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-align: center;
}

.text-button {
  justify-self: end;
  border: 0;
  padding: 0.45rem 0;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.text-button:hover,
.text-button:focus-visible {
  color: var(--cream);
}

.book-frame {
  position: relative;
  width: min(100%, 1280px);
  margin-inline: auto;
  display: grid;
  place-items: center;
  perspective: 2200px;
}

.book-frame::before {
  content: "";
  position: absolute;
  z-index: -2;
  width: 88%;
  height: 14%;
  bottom: -5%;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.58);
  filter: blur(26px);
}

.book {
  position: relative;
  width: min(100%, calc((100svh - 12rem) * 4 / 3));
  aspect-ratio: 4 / 3;
  transform-style: preserve-3d;
  isolation: isolate;
}

.book::before,
.book::after {
  content: "";
  position: absolute;
  inset: 0.45rem -0.45rem -0.55rem 0.45rem;
  z-index: -2;
  border-radius: 0.2rem 0.42rem 0.42rem 0.2rem;
  background: var(--paper-deep);
  box-shadow: 0 2.2rem 4.5rem rgba(0, 0, 0, 0.48);
}

.book::after {
  inset: 0.22rem -0.22rem -0.28rem 0.22rem;
  z-index: -1;
  background: #e3d7c1;
}

.book-page {
  position: absolute;
  inset: 0;
  overflow: hidden;
  border-radius: 0.16rem 0.35rem 0.35rem 0.16rem;
  background: var(--paper);
  box-shadow:
    inset 0 0 0 1px rgba(70, 52, 34, 0.1),
    inset -0.8rem 0 1.8rem rgba(96, 71, 45, 0.07);
  transform-style: preserve-3d;
  backface-visibility: hidden;
}

.book-page--under {
  transform: scale(0.992) translateX(0.2%);
  animation: settle-page var(--page-duration) ease-out forwards;
}

.book-page--forward {
  transform-origin: left center;
  animation: turn-forward var(--page-duration) cubic-bezier(0.64, 0, 0.3, 1) forwards;
}

.book-page--backward {
  transform-origin: right center;
  animation: turn-backward var(--page-duration) cubic-bezier(0.64, 0, 0.3, 1) forwards;
}

.poster-page,
.poster-page img {
  width: 100%;
  height: 100%;
}

.poster-page {
  margin: 0;
  background: #e9dfcc;
}

.poster-page img {
  display: block;
  object-fit: cover;
  user-select: none;
  -webkit-user-drag: none;
}

.cover-page {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #eee7d6;
  color: var(--ink);
  text-align: center;
}

.cover-page::before {
  content: "";
  position: absolute;
  z-index: 3;
  inset: 2.8%;
  border: 1px solid rgba(79, 59, 39, 0.18);
  pointer-events: none;
}

.cover-page__art {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  user-select: none;
  -webkit-user-drag: none;
}

.cover-page__content {
  position: absolute;
  z-index: 2;
  left: 50%;
  bottom: 3.2%;
  width: min(86%, 31rem);
  padding: clamp(0.7rem, 1.7vw, 1.15rem) clamp(1rem, 2.8vw, 2rem) clamp(0.65rem, 1.5vw, 1rem);
  border-top: 1px solid rgba(75, 62, 45, 0.14);
  border-bottom: 1px solid rgba(75, 62, 45, 0.14);
  background: rgba(242, 236, 222, 0.91);
  box-shadow: 0 0.55rem 1.8rem rgba(75, 56, 34, 0.07);
  transform: translateX(-50%);
  backdrop-filter: blur(2px);
}

.cover-page__eyebrow {
  display: block;
  margin-bottom: clamp(0.2rem, 0.7vw, 0.5rem);
  color: #756957;
  font-size: clamp(0.48rem, 0.82vw, 0.66rem);
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.cover-page h1 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.7rem, 5.6vw, 4.75rem);
  font-weight: 400;
  letter-spacing: -0.045em;
  line-height: 0.9;
}

.cover-page__ampersand {
  color: var(--terracotta);
  font-style: italic;
  font-weight: 400;
}

.cover-page p {
  max-width: 34rem;
  margin: clamp(0.15rem, 0.5vw, 0.35rem) auto 0;
  color: #675c4e;
  font-size: clamp(0.45rem, 0.78vw, 0.62rem);
  letter-spacing: 0.18em;
  line-height: 1.4;
  text-transform: uppercase;
}

.cover-page__open {
  margin-top: clamp(0.35rem, 0.9vw, 0.7rem);
  border: 1px solid rgba(64, 51, 38, 0.48);
  border-radius: 999px;
  padding: clamp(0.35rem, 0.75vw, 0.55rem) clamp(0.72rem, 1.3vw, 1rem);
  background: transparent;
  color: #514638;
  cursor: pointer;
  font-size: clamp(0.44rem, 0.75vw, 0.58rem);
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.cover-page__open:hover,
.cover-page__open:focus-visible {
  background: var(--ink);
  color: var(--paper);
}

.page-edge {
  position: absolute;
  z-index: 5;
  top: 0;
  bottom: 0;
  width: 13%;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.page-edge::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 1.6rem;
  height: 1.6rem;
  border-top: 1px solid rgba(255, 255, 255, 0.7);
  border-right: 1px solid rgba(255, 255, 255, 0.7);
  opacity: 0;
  transition: opacity 180ms ease;
}

.page-edge:hover::after,
.page-edge:focus-visible::after {
  opacity: 0.9;
}

.page-edge--previous {
  left: 0;
}

.page-edge--previous::after {
  left: 1.2rem;
  transform: translateY(-50%) rotate(-135deg);
}

.page-edge--next {
  right: 0;
}

.page-edge--next::after {
  right: 1.2rem;
  transform: translateY(-50%) rotate(45deg);
}

.book-controls {
  width: min(100%, 34rem);
  margin-inline: auto;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1.2rem;
}

.round-button {
  width: 2.8rem;
  height: 2.8rem;
  border: 1px solid rgba(245, 237, 223, 0.3);
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.035);
  color: var(--cream);
  cursor: pointer;
  font-size: 1.1rem;
  transition: background 180ms ease, border-color 180ms ease, opacity 180ms ease;
}

.round-button:hover,
.round-button:focus-visible {
  border-color: rgba(245, 237, 223, 0.72);
  background: rgba(255, 255, 255, 0.1);
}

.round-button:disabled {
  cursor: default;
  opacity: 0.22;
}

.pagination {
  display: grid;
  gap: 0.5rem;
  text-align: center;
}

.pagination__label {
  min-height: 1em;
  color: var(--muted);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.pagination__dots {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
}

.pagination__dot {
  width: 0.34rem;
  height: 0.34rem;
  border-radius: 50%;
  background: rgba(245, 237, 223, 0.24);
  transition: transform 220ms ease, background 220ms ease;
}

.pagination__dot.is-active {
  background: var(--cream);
  transform: scale(1.35);
}

.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;
}

@keyframes turn-forward {
  0% {
    transform: rotateY(0deg) translateZ(0);
    filter: brightness(1);
  }
  48% {
    filter: brightness(0.72);
  }
  100% {
    transform: rotateY(-104deg) translateZ(0.5rem);
    filter: brightness(0.5);
    opacity: 0;
  }
}

@keyframes turn-backward {
  0% {
    transform: rotateY(0deg) translateZ(0);
    filter: brightness(1);
  }
  48% {
    filter: brightness(0.72);
  }
  100% {
    transform: rotateY(104deg) translateZ(0.5rem);
    filter: brightness(0.5);
    opacity: 0;
  }
}

@keyframes settle-page {
  to {
    transform: scale(1) translateX(0);
  }
}

@media (max-width: 720px) {
  .book-app {
    grid-template-rows: auto 1fr auto;
    padding: 0.85rem 0.65rem 1rem;
  }

  .book-header {
    grid-template-columns: 1fr auto;
  }

  .book-header__hint {
    display: none;
  }

  .book {
    width: min(100%, calc((100svh - 9.5rem) * 4 / 3));
  }

  .page-edge {
    width: 20%;
  }

  .page-edge::after {
    display: none;
  }

  .cover-page {
    padding: 0;
  }

  .cover-page h1 {
    font-size: clamp(1.55rem, 8.2vw, 2.8rem);
  }
}

@media (max-height: 620px) and (orientation: landscape) {
  .book-app {
    grid-template-rows: 1fr auto;
    gap: 0.65rem;
    padding: 0.65rem;
  }

  .book-header {
    display: none;
  }

  .book {
    width: min(100%, calc((100svh - 4.8rem) * 4 / 3));
  }

  .round-button {
    width: 2.25rem;
    height: 2.25rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --page-duration: 1ms;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 1ms !important;
    transition-duration: 1ms !important;
  }
}