/* =========================================================
     BOOK DETAILS
     Scoped to #book-details
  ========================================================= */

  /* ---------- Section base / tokens ---------- */
  #book-details {
    position: relative;
    z-index: 1;
    overflow: hidden;
    padding: clamp(4.75rem, 6.5vw, 6.25rem) 0;

    --bd-gap-1: clamp(0.85rem, 0.6rem + 1vw, 1.35rem);
    --bd-gap-2: clamp(1.15rem, 0.85rem + 1.7vw, 2.2rem);
    --bd-gap-3: clamp(1.8rem, 1.2rem + 2.6vw, 3.2rem);

    --bd-h2: clamp(1.85rem, 1.2rem + 2.4vw, 2.85rem);
    --bd-h3: clamp(1.15rem, 1rem + 0.9vw, 1.6rem);
    --bd-body: clamp(1.03rem, 0.96rem + 0.6vw, 1.24rem);
    --bd-small: clamp(0.92rem, 0.88rem + 0.28vw, 1.06rem);

    --bd-measure: 62ch;

    --bd-ink: var(--default-color, #e9eef0);
    --bd-head: var(--heading-color, #ffffff);
    --bd-accent: var(--accent-color, #46d9ff);
    --bd-surface: var(--surface-color, rgba(255, 255, 255, 0.06));
    --bd-contrast: var(--contrast-color, #0b0f12);

    --bd-neon-cyan: #46d9ff;
    --bd-neon-magenta: #ff4fd1;

    --bd-panel-bg:
      radial-gradient(1100px 520px at 18% 0%, rgba(70, 217, 255, 0.12), transparent 60%),
      radial-gradient(950px 480px at 92% 18%, rgba(255, 79, 209, 0.11), transparent 62%),
      linear-gradient(to bottom, rgba(255, 255, 255, 0.07), rgba(255, 255, 255, 0.035));
  }

  #book-details .row.align-items-start {
    padding-top: clamp(0.25rem, 0.4vw, 0.9rem);
  }

  /* ---------- Fireflies ---------- */
  #book-details .book-fireflies-container {
    position: absolute;
    inset: 0;
    z-index: 0;
    overflow: hidden;
    pointer-events: none;
  }

  #book-details .book-firefly {
    position: absolute;
    border-radius: 50%;
    opacity: 0;
    pointer-events: none;
    background: radial-gradient(
      circle,
      rgba(255, 245, 180, 0.9) 40%,
      rgba(255, 245, 180, 0.2) 80%,
      transparent 100%
    );
  }

  @keyframes bookTwinkle {
    0%, 100% { opacity: 0; }
    40% { opacity: 0.9; }
    60% { opacity: 0.4; }
  }

  @keyframes bookDrift {
    0% { transform: translate(0, 0); }
    25% { transform: translate(-1vw, 1vh); }
    50% { transform: translate(1.5vw, -1vh); }
    75% { transform: translate(-0.5vw, 0.5vh); }
    100% { transform: translate(0, 0); }
  }

  /* Keep real content above decorative effects */
  #book-details .container,
  #book-details .row,
  #book-details .book-details-img,
  #book-details .book-details-content {
    position: relative;
    z-index: 2;
  }

  /* ---------- Left column ---------- */
  #book-details .book-details-img {
    position: relative;
    margin-top: clamp(0.25rem, 0.6vw, 1rem);
    overflow: hidden;
    border-radius: 14px;
    transition: transform 0.25s ease;
  }

  #book-details .book-details-img:hover {
    transform: translateY(-8px);
  }

  #book-details .book-details-img img {
    display: block;
    width: 100%;
    height: auto;
    border-radius: 14px;
    box-shadow:
      0 24px 54px rgba(0, 0, 0, 0.35),
      0 8px 18px rgba(0, 0, 0, 0.18);
  }

  #book-details .book-details-meta {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
    padding: 18px;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.18));
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
  }

  #book-details .detail-item {
    display: flex;
    align-items: center;
    gap: 10px;
  }

  #book-details .detail-item i {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.9);
    opacity: 0.9;
  }

  #book-details .detail-item span {
    display: block;
    margin-bottom: 2px;
    font-size: 12px;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.65);
  }

  #book-details .detail-item p {
    margin: 0;
    font-size: 14px;
    font-weight: 800;
    color: rgba(255, 255, 255, 0.92);
  }

  /* ---------- Right column panel ---------- */
  #book-details .book-details-content {
    position: relative;
    isolation: isolate;
    overflow: hidden;
    max-width: var(--bd-measure);
    margin-top: clamp(0.25rem, 0.6vw, 1rem);
    margin-inline: auto;
    padding: clamp(1.5rem, 1.1rem + 1.9vw, 2.35rem);
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: 18px;
    background: var(--bd-panel-bg);
    box-shadow:
      0 26px 70px rgba(0, 0, 0, 0.3),
      0 0 0 1px rgba(255, 255, 255, 0.05) inset,
      0 0 18px rgba(70, 217, 255, 0.08),
      0 0 18px rgba(255, 79, 209, 0.06);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
  }

  /*
    Decorative sheen layer.
    isolation + explicit child z-index keeps this from blocking text/buttons.
  */
  #book-details .book-details-content::before {
    content: "";
    position: absolute;
    inset: -45% -30%;
    z-index: 0;
    opacity: 0.12;
    pointer-events: none;
    transform: rotate(-6deg);
    background: linear-gradient(
      115deg,
      transparent 40%,
      rgba(255, 255, 255, 0.1) 48%,
      transparent 56%
    );
  }

  #book-details .book-details-content > * {
    position: relative;
    z-index: 2;
  }

  #book-details .book-details-content h2 {
    margin: 0 0 clamp(0.95rem, 0.75rem + 0.7vw, 1.35rem);
    font-size: var(--bd-h2);
    line-height: 1.05;
    font-weight: 900;
    letter-spacing: 0.03em;
    color: var(--bd-head);
    text-shadow:
      0 0 16px rgba(70, 217, 255, 0.1),
      0 0 18px rgba(255, 79, 209, 0.08);
  }

  #book-details .book-details-content h3 {
    margin: clamp(1.25rem, 1rem + 1vw, 1.9rem) 0 0.8rem;
    font-size: var(--bd-h3);
    font-weight: 800;
    letter-spacing: 0.02em;
    color: var(--bd-head);
  }

  #book-details .book-details-content p {
    margin: 0 0 clamp(1.05rem, 0.85rem + 0.7vw, 1.45rem);
    font-size: var(--bd-body);
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.86);
  }

  /* ---------- Category chips ---------- */
  #book-details .book-category {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 0 0 clamp(1.05rem, 0.9rem + 0.8vw, 1.85rem);
  }

  #book-details .book-category span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 0.48rem 0.85rem;
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: 999px;
    font-size: var(--bd-small);
    font-weight: 800;
    line-height: 1;
    color: rgba(255, 255, 255, 0.86);
    background: linear-gradient(
      135deg,
      rgba(70, 217, 255, 0.16),
      rgba(255, 79, 209, 0.12)
    );
  }

  #book-details .book-category i {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.86);
  }

  /* ---------- Editorial reviews ---------- */
  #book-details .editorial-reviews {
    margin-top: clamp(1.4rem, 1.15rem + 1.4vw, 2.2rem);
    padding-top: clamp(1.1rem, 0.95rem + 1vw, 1.75rem);
    border-top: 1px solid rgba(255, 255, 255, 0.12);
  }

  #book-details .review-block {
    position: relative;
    margin-top: clamp(1rem, 0.85rem + 1vw, 1.6rem);
    padding: clamp(1.05rem, 0.9rem + 1.05vw, 1.6rem);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 16px;
    background:
      radial-gradient(640px 240px at 18% 0%, rgba(70, 217, 255, 0.08), transparent 62%),
      radial-gradient(560px 240px at 95% 28%, rgba(255, 79, 209, 0.08), transparent 62%),
      rgba(255, 255, 255, 0.04);
    box-shadow: 0 18px 44px rgba(0, 0, 0, 0.22);
  }

  #book-details .review-block .quote {
    margin: 0 0 0.85rem;
    padding-left: 1.1rem;
    border-left: 3px solid rgba(70, 217, 255, 0.45);
    font-size: clamp(1.02rem, 0.96rem + 0.5vw, 1.18rem);
    line-height: 1.72;
    font-style: italic;
    color: rgba(255, 255, 255, 0.86);
  }

  #book-details .review-block .reviewer {
    margin: 0;
    font-size: var(--bd-small);
    color: rgba(255, 255, 255, 0.65);
  }

  /* Kill decorative quote marks cleanly */
  #book-details .review-block .quote::before,
  #book-details .review-block .quote::after,
  #book-details .review-block::before,
  #book-details .review-block::after {
    content: none !important;
    display: none !important;
  }

  /* ---------- Purchase buttons ---------- */
  #book-details .book-purchase-buttons {
    position: relative;
    z-index: 5;
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: clamp(1.1rem, 0.9rem + 1vw, 1.8rem);
  }

  #book-details a.book-details-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 12px 22px;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 999px;
    font-size: var(--bd-small);
    font-weight: 900;
    letter-spacing: 0.01em;
    text-decoration: none !important;
    color: rgba(255, 255, 255, 0.92);
    background: linear-gradient(
      135deg,
      rgba(70, 217, 255, 0.22),
      rgba(255, 79, 209, 0.18)
    );
    box-shadow:
      0 14px 30px rgba(0, 0, 0, 0.22),
      0 0 0 1px rgba(255, 255, 255, 0.06) inset;
    transition: transform 0.18s ease, box-shadow 0.18s ease, filter 0.18s ease;
  }

  #book-details a.book-details-cta i {
    transition: transform 0.18s ease;
  }

  #book-details a.book-details-cta:hover {
    transform: translateY(-2px);
    filter: saturate(1.06);
    box-shadow:
      0 18px 38px rgba(0, 0, 0, 0.28),
      0 0 0 2px rgba(255, 79, 209, 0.14),
      0 0 20px rgba(70, 217, 255, 0.12);
  }

  #book-details a.book-details-cta:hover i {
    transform: translateX(4px);
  }

  #book-details a.book-details-cta:focus-visible {
    outline: 3px solid rgba(70, 217, 255, 0.45);
    outline-offset: 3px;
  }

  #book-details a.book-details-cta.alt {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.14);
  }

  /* Desktop-only left column button layout */
  #book-details .hide-on-mobile .book-purchase-buttons {
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    margin-top: 1rem;
  }

  #book-details .hide-on-mobile .book-details-cta {
    width: min(280px, 100%);
  }

  /* ---------- Visibility helpers ---------- */
  .hide-on-mobile {
    display: block;
  }

  .show-on-mobile {
    display: none !important;
  }

  #book-details .book-details-mobile {
    display: none;
  }

  /* ---------- Large-screen rebalance ---------- */
  @media (min-width: 992px) {
    #book-details .book-details-img {
      max-width: 420px;
      margin-right: auto;
      margin-left: auto;
    }

    #book-details .book-details-content {
      max-width: 72ch;
    }
  }

  @media (min-width: 1200px) {
    #book-details .book-details-img {
      max-width: 400px;
    }

    #book-details .book-details-content {
      max-width: 78ch;
    }
  }

  /* =========================================================
     MOBILE
     Strategy:
     - hide desktop-only text blocks
     - show a simplified mobile card
     - keep purchase buttons visible inside that card
  ========================================================= */
  @media (max-width: 768px) {
    .hide-on-mobile {
      display: none !important;
    }

    .show-on-mobile {
      display: block !important;
    }

    #book-details {
      padding: 2.75rem 0;
    }

    /*
      On mobile the outer desktop panel becomes a simple wrapper.
      The actual visible card is .book-details-mobile.
    */
    #book-details .book-details-content {
      margin-top: 0;
      padding: 0;
      background: transparent;
      border: 0;
      box-shadow: none;
      backdrop-filter: none;
      -webkit-backdrop-filter: none;
    }

    #book-details .book-details-content::before {
      content: none;
    }

    #book-details .book-details-content > h2,
    #book-details .book-details-content > .book-category,
    #book-details .book-details-content > p,
    #book-details .book-details-content > .editorial-reviews {
      display: none !important;
    }

    #book-details .book-details-mobile {
      display: block !important;
      padding: 1.2rem;
      border: 1px solid rgba(255, 255, 255, 0.12);
      border-radius: 16px;
      color: rgba(255, 255, 255, 0.88);
      background: rgba(255, 255, 255, 0.05);
      box-shadow: 0 14px 32px rgba(0, 0, 0, 0.22);
    }

    #book-details .book-details-mobile h2 {
      margin: 0 0 0.85rem;
      font-size: clamp(1.35rem, 1.1rem + 1.3vw, 2rem);
      font-weight: 900;
      color: rgba(255, 255, 255, 0.94);
    }

    #book-details .book-details-mobile .book-category {
      margin-bottom: 1rem;
    }

    #book-details .mobile-hook {
      margin-bottom: 0.75rem;
      font-weight: 750;
      font-style: italic;
    }

    #book-details .mobile-blurb {
      margin-bottom: 1rem;
      font-size: clamp(0.98rem, 0.92rem + 0.5vw, 1.12rem);
      line-height: 1.6;
    }

    #book-details .editorial-snippets h3 {
      margin: 1rem 0 0.65rem;
      font-size: 1rem;
      font-weight: 850;
    }

    #book-details .editorial-snippets p {
      margin: 0.65rem 0;
      padding-left: 0.9rem;
      border-left: 3px solid rgba(70, 217, 255, 0.45);
      font-size: 0.95rem;
      line-height: 1.5;
    }

    #book-details .editorial-snippets span {
      display: inline-block;
      margin-top: 0.15rem;
      font-size: 0.9rem;
      color: rgba(255, 255, 255, 0.68);
    }

    #book-details .book-purchase-buttons {
      gap: 10px;
      margin-top: 1rem;
    }

    #book-details a.book-details-cta {
      width: 100%;
    }
  }

  /* ---------- Small phones ---------- */
  @media (max-width: 576px) {
    #book-details {
      padding: 2.25rem 0;
    }

    #book-details .book-details-mobile {
      padding: 1.05rem;
      border: 1px solid rgba(255, 255, 255, 0.1);
      border-radius: 14px;
      background: rgba(255, 255, 255, 0.045);
      box-shadow: 0 10px 22px rgba(0, 0, 0, 0.18);
    }

    #book-details .book-details-mobile h2 {
      margin-bottom: 0.6rem;
    }

    #book-details .book-details-mobile .book-category {
      gap: 8px;
      margin-bottom: 0.85rem;
    }

    #book-details .book-details-mobile .book-category span {
      padding: 0.42rem 0.68rem;
      font-size: 0.92rem;
    }

    #book-details .mobile-hook {
      margin-bottom: 0.65rem;
      line-height: 1.55;
    }

    #book-details .mobile-blurb {
      margin-bottom: 0.85rem;
      line-height: 1.6;
    }

    #book-details .editorial-snippets h3 {
      margin: 0.75rem 0 0.45rem;
    }

    #book-details .editorial-snippets p {
      margin: 0.45rem 0;
      padding-left: 0.75rem;
      font-size: 0.93rem;
      line-height: 1.45;
    }

    #book-details .editorial-snippets span {
      font-size: 0.88rem;
    }

    #book-details .book-details-mobile .book-purchase-buttons {
      margin-top: 0.85rem;
      gap: 10px;
    }

    #book-details .book-details-mobile a.book-details-cta {
      padding: 11px 16px;
      font-size: 0.95rem;
    }
  }