.online-books-page,
.online-book-page {
  --books-accent: #be132d;
  --books-accent-dark: #941024;
  --books-ink: #1e2933;
  --books-muted: #65717d;
  --books-paper: #f4f1eb;
}

.online-books-hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  margin-bottom: 30px;
  padding: clamp(24px, 4vw, 46px);
  overflow: hidden;
  border-radius: 18px;
  background: linear-gradient(135deg, #212d39 0%, #34495a 72%, #be132d 160%);
  color: #fff;
  box-shadow: 0 16px 34px rgba(31, 43, 55, .14);
}

.online-books-hero h1 {
  margin: 5px 0 12px;
  color: #fff;
  font-size: clamp(2rem, 4vw, 3.2rem);
  font-weight: 800;
}

.online-books-hero p {
  max-width: 760px;
  margin: 0;
  color: rgba(255, 255, 255, .84);
  font-size: 1.08rem;
}

.online-books-hero > i {
  color: rgba(255, 255, 255, .16);
  font-size: clamp(5rem, 12vw, 9rem);
  transform: rotate(-7deg);
}

.online-books-kicker {
  color: #f2b8c1;
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.online-books-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  margin-bottom: 32px;
}

.online-book-card {
  display: flex;
  min-width: 0;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid #dfe4e8;
  border-radius: 14px;
  background: #fff;
  box-shadow: 0 8px 24px rgba(31, 43, 55, .07);
  transition: transform .2s ease, box-shadow .2s ease;
}

.online-book-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 34px rgba(31, 43, 55, .12);
}

.online-book-cover-wrap {
  display: flex;
  min-height: 310px;
  align-items: center;
  justify-content: center;
  padding: 22px;
  overflow: hidden;
  background: var(--books-paper);
}

.online-book-cover {
  display: block;
  width: auto;
  max-width: 100%;
  height: 285px;
  object-fit: contain;
  box-shadow: 0 10px 22px rgba(31, 43, 55, .2);
  user-select: none;
  -webkit-user-drag: none;
}

.online-book-card-body {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  align-items: flex-start;
  padding: 20px;
}

.online-book-card h2 {
  margin: 7px 0 10px;
  font-size: 1.16rem;
  font-weight: 750;
  line-height: 1.35;
}

.online-book-card h2 a {
  color: var(--books-ink);
  text-decoration: none;
}

.online-book-card p {
  color: var(--books-muted);
  line-height: 1.55;
}

.online-book-pages {
  color: var(--books-accent);
  font-size: .82rem;
  font-weight: 750;
}

.online-book-card .btn-primary {
  border-color: var(--books-accent);
  background: var(--books-accent);
}

.online-book-card .btn-primary:hover {
  border-color: var(--books-accent-dark);
  background: var(--books-accent-dark);
}

.online-book-heading {
  margin-bottom: 22px;
}

.online-book-heading h1 {
  margin: 10px 0 8px;
  color: var(--books-ink);
  font-size: clamp(1.7rem, 3vw, 2.5rem);
  font-weight: 800;
}

.online-book-heading p {
  margin: 0;
  color: var(--books-muted);
}

.online-book-back {
  color: var(--books-accent);
  font-weight: 700;
  text-decoration: none;
}

.online-book-viewer {
  overflow: hidden;
  border: 1px solid #d7dde2;
  border-radius: 14px;
  background: #27333e;
  box-shadow: 0 18px 40px rgba(25, 35, 44, .18);
}

.online-book-toolbar {
  position: sticky;
  z-index: 5;
  top: 0;
  display: flex;
  min-height: 62px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 10px 14px;
  border-bottom: 1px solid rgba(255, 255, 255, .09);
  background: #1e2933;
  color: #fff;
}

.online-book-toolbar .btn {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  gap: 7px;
  justify-content: center;
  border: 1px solid rgba(255, 255, 255, .12);
  background: rgba(255, 255, 255, .08);
  color: #fff;
}

.online-book-toolbar .btn:hover:not(:disabled) {
  background: rgba(255, 255, 255, .16);
}

.online-book-toolbar .btn:disabled {
  opacity: .38;
}

.online-book-page-control {
  display: flex;
  align-items: center;
  gap: 7px;
  margin: 0 4px;
  color: rgba(255, 255, 255, .78);
  white-space: nowrap;
}

.online-book-page-input {
  width: 76px;
  height: 40px;
  border-color: rgba(255, 255, 255, .18);
  background: #fff;
  text-align: center;
}

.online-book-toolbar-separator {
  width: 1px;
  height: 28px;
  margin: 0 3px;
  background: rgba(255, 255, 255, .14);
}

.online-book-stage {
  position: relative;
  max-height: min(78vh, 980px);
  min-height: 520px;
  padding: 24px;
  overflow: auto;
  outline: 0;
  background: radial-gradient(circle at 50% 0%, #465563, #27333e 65%);
  text-align: center;
  overscroll-behavior: contain;
}

.online-book-canvas {
  display: block;
  width: 100%;
  max-width: none;
  height: auto;
  margin: 0 auto;
  background: #fff;
  box-shadow: 0 8px 24px rgba(0, 0, 0, .32);
  transition: width .18s ease;
  user-select: none;
}

.online-book-loader {
  position: absolute;
  z-index: 3;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  background: rgba(39, 51, 62, .76);
  color: #fff;
  backdrop-filter: blur(2px);
}

.online-book-loader[hidden] {
  display: none;
}

.online-book-error {
  position: absolute;
  z-index: 4;
  top: 30px;
  right: 30px;
  left: 30px;
}

.online-book-mobile-nav {
  display: none;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 12px;
  background: #fff;
}

.online-book-mobile-counter {
  color: var(--books-ink);
  font-weight: 750;
}

.online-book-protection-note {
  margin: 0;
  padding: 12px 18px;
  border-top: 1px solid rgba(255, 255, 255, .08);
  background: #1e2933;
  color: rgba(255, 255, 255, .65);
  font-size: .84rem;
  text-align: center;
}

.online-book-viewer:fullscreen {
  display: flex;
  flex-direction: column;
  border: 0;
  border-radius: 0;
}

.online-book-viewer:fullscreen .online-book-stage {
  max-height: none;
  flex: 1 1 auto;
}

@media (max-width: 991.98px) {
  .online-books-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .online-book-stage {
    min-height: 440px;
  }
}

@media (max-width: 767.98px) {
  .online-books-hero > i,
  .online-book-toolbar .online-book-prev,
  .online-book-toolbar .online-book-next,
  .online-book-toolbar-separator,
  .online-book-toolbar .online-book-zoom-out,
  .online-book-toolbar .online-book-zoom-in {
    display: none;
  }

  .online-books-grid {
    grid-template-columns: 1fr;
  }

  .online-book-card {
    display: grid;
    grid-template-columns: minmax(130px, 38%) minmax(0, 1fr);
  }

  .online-book-cover-wrap {
    min-height: 0;
    padding: 14px;
  }

  .online-book-cover {
    width: 100%;
    height: auto;
    max-height: 250px;
  }

  .online-book-card-body {
    padding: 16px;
  }

  .online-book-stage {
    min-height: 360px;
    padding: 10px;
  }

  .online-book-mobile-nav {
    display: flex;
  }

  .online-book-protection-note {
    display: none;
  }
}

@media (max-width: 479.98px) {
  .online-books-hero {
    padding: 22px;
  }

  .online-book-card {
    display: flex;
  }

  .online-book-cover {
    width: auto;
    height: 260px;
  }

  .online-book-toolbar {
    justify-content: space-between;
  }

  .online-book-page-control {
    font-size: .85rem;
  }

  .online-book-page-input {
    width: 62px;
  }

  .online-book-stage {
    min-height: 290px;
  }
}