:root {
  --ink: #113c48;
  --ink-2: #092c36;
  --cream: #fff8eb;
  --paper: #fbf1dc;
  --sea-deep: #0f4c5c;
  --sun: #f4c85d;
  --coral: #e45642;
  --muted: #657b78;
  --shadow: 0 28px 80px rgba(8, 35, 42, 0.24);
  color-scheme: light;
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  height: 100%;
  scroll-behavior: smooth;
}

body {
  min-height: 100%;
  margin: 0;
  color: var(--ink);
  overflow: hidden;
  background:
    linear-gradient(rgba(255, 248, 235, 0.82), rgba(255, 248, 235, 0.82)),
    repeating-linear-gradient(0deg, transparent 0 138px, rgba(18, 63, 75, 0.14) 139px 142px),
    repeating-linear-gradient(90deg, transparent 0 288px, rgba(18, 63, 75, 0.1) 289px 291px),
    linear-gradient(140deg, #fbf4e1 0%, #cde7e8 100%);
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
}

button {
  font: inherit;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 12;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 16px clamp(18px, 4vw, 48px);
  pointer-events: none;
}

.brand,
.book-controls {
  pointer-events: auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 11px 14px;
  border: 1px solid rgba(18, 63, 75, 0.12);
  border-radius: 8px;
  background: rgba(255, 248, 235, 0.86);
  backdrop-filter: blur(16px);
  box-shadow: 0 14px 30px rgba(8, 35, 42, 0.1);
  font-weight: 850;
  letter-spacing: 0.04em;
  text-decoration: none;
  text-transform: uppercase;
}

.record-dot {
  width: 18px;
  height: 18px;
  border-radius: 6px;
  background: var(--coral);
  box-shadow: 0 0 0 4px var(--sun);
}

.book-controls {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px;
  border: 1px solid rgba(18, 63, 75, 0.12);
  border-radius: 8px;
  background: rgba(255, 248, 235, 0.86);
  backdrop-filter: blur(16px);
  box-shadow: 0 14px 30px rgba(8, 35, 42, 0.1);
}

.nav-button {
  min-height: 40px;
  padding: 0 14px;
  border: 0;
  border-radius: 7px;
  color: var(--cream);
  background: var(--sea-deep);
  font-weight: 850;
  cursor: pointer;
}

.nav-button:disabled {
  cursor: default;
  opacity: 0.38;
}

.page-status {
  min-width: 104px;
  margin: 0;
  color: var(--ink-2);
  font-size: 0.84rem;
  font-weight: 850;
  text-align: center;
  text-transform: uppercase;
}

.book-shell {
  height: 100vh;
  padding: 76px 0 58px;
}

.flipbook {
  display: flex;
  height: 100%;
  overflow-x: auto;
  overflow-y: hidden;
  scroll-behavior: smooth;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  touch-action: pan-x;
}

.flipbook::-webkit-scrollbar {
  display: none;
}

.page {
  position: relative;
  flex: 0 0 100vw;
  display: grid;
  place-items: center;
  min-width: 0;
  padding: clamp(14px, 3vw, 34px);
  scroll-snap-align: start;
  perspective: 1800px;
}

.page-paper {
  position: relative;
  width: min(1180px, 100%);
  height: min(720px, 100%);
  max-height: calc(100vh - 150px);
  overflow: hidden;
  border: 1px solid rgba(100, 74, 36, 0.18);
  border-radius: 8px;
  background:
    linear-gradient(90deg, rgba(80, 54, 20, 0.1) 0 12px, transparent 46px),
    linear-gradient(135deg, #fffaf0 0%, var(--paper) 100%);
  box-shadow:
    var(--shadow),
    inset 18px 0 28px rgba(84, 58, 24, 0.08),
    inset -10px 0 18px rgba(255, 255, 255, 0.45);
  touch-action: pan-y;
}

.page-paper::before {
  position: absolute;
  inset: 16px;
  z-index: 0;
  border: 1px solid rgba(18, 63, 75, 0.1);
  border-radius: 5px;
  pointer-events: none;
  content: "";
}

.page.is-turning .page-paper {
  animation: pageTurn 520ms cubic-bezier(0.2, 0.76, 0.24, 1);
}

@keyframes pageTurn {
  0% {
    transform: rotateY(0deg) translateX(0);
  }
  45% {
    transform: rotateY(-5deg) translateX(-8px);
  }
  100% {
    transform: rotateY(0deg) translateX(0);
  }
}

.cover-spread,
.prose-spread,
.credits-spread,
.sources-spread {
  display: grid;
  gap: clamp(18px, 3vw, 42px);
  padding: clamp(26px, 5vw, 58px);
}

.cover-spread {
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1.05fr);
  align-items: center;
}

.kicker {
  display: block;
  margin: 0 0 14px;
  color: var(--coral);
  font-size: 0.76rem;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 720px;
  margin-bottom: 24px;
  font-size: clamp(3rem, 7vw, 6rem);
  line-height: 0.91;
  letter-spacing: 0;
  text-wrap: balance;
}

h2 {
  margin-bottom: 18px;
  font-size: clamp(2.3rem, 5vw, 5rem);
  line-height: 0.98;
  text-wrap: balance;
}

h3 {
  margin-bottom: 8px;
  font-size: 1.12rem;
}

.lede,
.prose-spread p,
.achievement-grid p,
.sources-spread li,
.closing-line {
  color: var(--ink-2);
  font-size: 1.04rem;
  line-height: 1.58;
}

.cover-frame {
  position: relative;
  z-index: 1;
  margin: 0;
  padding: 14px;
  transform: rotate(1deg);
  background: var(--cream);
  box-shadow: 0 18px 48px rgba(8, 35, 42, 0.2);
}

.cover-frame::before,
.cover-frame::after {
  position: absolute;
  left: 8%;
  right: 8%;
  height: 24px;
  border-radius: 8px;
  background:
    repeating-linear-gradient(90deg, transparent 0 28px, var(--cream) 29px 44px),
    var(--sea-deep);
  content: "";
}

.cover-frame::before {
  top: -15px;
}

.cover-frame::after {
  bottom: -15px;
}

.cover-frame img {
  aspect-ratio: 5 / 4;
  width: 100%;
  object-fit: cover;
  border: 5px solid var(--ink);
}

.cover-frame figcaption,
.caption,
.turn-hint {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 850;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.cover-frame figcaption {
  padding-top: 10px;
  text-align: center;
}

.turn-hint {
  margin: 24px 0 0;
}

.prose-spread {
  align-content: center;
  max-width: 860px;
  margin: 0 auto;
  overflow-y: auto;
}

.single-photo-spread {
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
  gap: 14px;
  padding: clamp(22px, 4vw, 42px);
  place-items: center;
}

.photo-card {
  position: relative;
  z-index: 1;
  display: block;
  width: min(760px, 92%);
  height: min(570px, 100%);
  min-height: 0;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
  perspective: 1600px;
  transform-style: preserve-3d;
}

.portrait-card {
  width: min(460px, 86%);
}

.landscape-card {
  width: min(840px, 92%);
}

.photo-face {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  overflow: hidden;
  border: 12px solid var(--cream);
  border-radius: 8px;
  background: var(--cream);
  box-shadow: 0 20px 52px rgba(8, 35, 42, 0.22);
  backface-visibility: hidden;
  transform-style: preserve-3d;
  transition: transform 520ms cubic-bezier(0.2, 0.76, 0.24, 1);
}

.photo-front {
  transform: rotateY(0deg);
}

.photo-back {
  align-content: center;
  justify-items: start;
  gap: 14px;
  padding: clamp(24px, 5vw, 58px);
  color: var(--cream);
  background:
    linear-gradient(rgba(15, 76, 92, 0.93), rgba(15, 76, 92, 0.93)),
    repeating-linear-gradient(0deg, transparent 0 30px, rgba(255, 248, 235, 0.1) 31px 32px);
  text-align: left;
  transform: rotateY(180deg);
}

.photo-back .kicker {
  color: var(--sun);
}

.photo-back strong {
  font-size: clamp(2rem, 5vw, 4.4rem);
  line-height: 0.96;
  text-wrap: balance;
}

.photo-back span:last-child {
  max-width: 580px;
  font-size: clamp(1.05rem, 2vw, 1.35rem);
  line-height: 1.5;
}

.photo-card.is-flipped .photo-front {
  transform: rotateY(-180deg);
}

.photo-card.is-flipped .photo-back {
  transform: rotateY(0deg);
}

.photo-card img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #f6ecd6;
}

.caption {
  position: relative;
  z-index: 1;
  margin: 0;
  text-align: center;
}

.dark-page .page-paper,
.credits-spread {
  color: var(--cream);
  background:
    radial-gradient(circle at 14% 20%, rgba(244, 200, 93, 0.18), transparent 30%),
    linear-gradient(135deg, #0e3c49, #0b2f3a);
}

.credits-spread {
  align-content: center;
}

.credits-spread .kicker,
.credits-spread h2,
.credits-spread h3,
.credits-spread p {
  color: var(--cream);
}

.achievement-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.achievement-grid article {
  min-height: 230px;
  padding: 22px;
  border: 1px solid rgba(255, 248, 235, 0.22);
  border-radius: 8px;
  background: rgba(255, 248, 235, 0.08);
}

.achievement-grid span {
  display: inline-flex;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  border-radius: 50%;
  color: var(--ink);
  background: var(--sun);
  font-weight: 900;
}

.achievement-grid p {
  color: rgba(255, 248, 235, 0.84);
  font-size: 0.94rem;
}

.sources-spread {
  align-content: center;
  overflow-y: auto;
}

.sources-spread ol {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: sources;
}

.sources-spread li {
  position: relative;
  padding: 20px 20px 20px 60px;
  border: 1px solid rgba(18, 63, 75, 0.14);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.5);
  counter-increment: sources;
}

.sources-spread li::before {
  position: absolute;
  top: 18px;
  left: 18px;
  display: grid;
  width: 30px;
  height: 30px;
  place-items: center;
  border-radius: 50%;
  color: var(--cream);
  background: var(--sea-deep);
  content: counter(sources);
  font-size: 0.86rem;
  font-weight: 900;
}

.sources-spread a {
  font-weight: 850;
}

.closing-line {
  margin: 0;
  font-weight: 850;
  text-align: center;
  text-transform: uppercase;
}

.page-dots {
  position: fixed;
  left: 50%;
  bottom: 18px;
  z-index: 12;
  display: flex;
  max-width: min(620px, calc(100vw - 28px));
  gap: 7px;
  overflow: hidden;
  transform: translateX(-50%);
}

.page-dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: rgba(17, 60, 72, 0.25);
  cursor: pointer;
}

.page-dot.is-active {
  width: 26px;
  border-radius: 999px;
  background: var(--coral);
}

@media (max-width: 1020px) {
  .cover-spread {
    grid-template-columns: 1fr;
  }

  .achievement-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 720px) {
  .site-header {
    padding: 10px 12px;
  }

  .brand {
    max-width: 48vw;
    padding: 9px 10px;
    font-size: 0.74rem;
  }

  .book-controls {
    gap: 6px;
    padding: 6px;
  }

  .nav-button {
    min-height: 36px;
    padding: 0 10px;
    font-size: 0.8rem;
  }

  .page-status {
    min-width: 70px;
    font-size: 0.68rem;
  }

  .book-shell {
    padding: 62px 0 42px;
  }

  .page {
    padding: 10px;
  }

  .page-paper {
    height: 100%;
    max-height: none;
    overflow-y: auto;
  }

  .cover-spread,
  .prose-spread,
  .credits-spread,
  .sources-spread {
    padding: 24px;
  }

  h1 {
    font-size: clamp(3rem, 15vw, 4.6rem);
  }

  h2 {
    font-size: clamp(2.2rem, 12vw, 3.8rem);
  }

  .lede,
  .prose-spread p,
  .achievement-grid p,
  .sources-spread li,
  .closing-line {
    font-size: 0.96rem;
  }

  .cover-frame {
    transform: none;
  }

  .single-photo-spread {
    padding: 20px 14px;
  }

  .photo-card,
  .portrait-card,
  .landscape-card {
    width: min(100%, 360px);
    height: min(610px, calc(100vh - 178px));
  }

  .landscape-card {
    height: min(360px, calc(100vh - 190px));
  }

  .photo-face {
    border-width: 8px;
  }

  .achievement-grid,
  .sources-spread ol {
    grid-template-columns: 1fr;
  }

  .page-dots {
    bottom: 12px;
    max-width: calc(100vw - 48px);
  }
}

@media (max-width: 420px) {
  .brand span:last-child {
    display: none;
  }

  .brand {
    max-width: none;
  }

  .page-status {
    display: none;
  }

  .photo-back {
    padding: 24px;
  }
}