/* Hero "book comes alive" demo (logic: static/js/hero-book.js). */

.book-demo {
  --paper: rgb(var(--c-surface));
  --hairline: rgb(var(--c-ink) / 0.07);
  --ink-soft: rgb(var(--c-slate-600));
  --highlight: rgb(var(--c-signal) / 0.42);
  --lamp: rgb(var(--c-amber-300) / 0.16);
  position: relative;
}

.book-demo__stage {
  position: relative;
  display: grid;
  gap: 1.25rem;
  grid-template-columns: minmax(0, 1fr);
}

@media (min-width: 900px) {
  .book-demo__stage { grid-template-columns: minmax(0, 1fr) minmax(0, 1.08fr); gap: 2.25rem; align-items: center; }
}

/* ── Chat panel ─────────────────────────────────────────────── */

.book-demo__chat {
  display: flex;
  flex-direction: column;
  min-height: 27rem;
  overflow: hidden;
  border-radius: 1.5rem;
  background: var(--paper);
  text-align: start;
  box-shadow:
    0 0 0 1px var(--hairline),
    0 40px 80px -40px rgb(4 43 41 / 0.35),
    0 24px 48px -30px rgb(0 0 0 / 0.18);
}

.book-demo__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: 2.75rem;
  padding-inline: 1rem;
  border-bottom: 1px solid var(--hairline);
  background: rgb(var(--c-mist) / 0.7);
  font-size: 0.75rem;
  font-weight: 500;
  color: rgb(var(--c-slate-500));
}

.book-demo__dots { display: flex; gap: 0.375rem; }
.book-demo__dots span { width: 0.75rem; height: 0.75rem; border-radius: 999px; background: #ff5f57; }
.book-demo__dots span:nth-child(2) { background: #febc2e; }
.book-demo__dots span:nth-child(3) { background: #28c840; }

.book-demo__thread {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 1rem;
  padding: 1.5rem 1.25rem 1rem;
}

.book-demo__question {
  align-self: flex-end;
  max-width: 88%;
  min-height: 3rem;
  padding: 0.75rem 1rem;
  border-radius: 1.25rem;
  border-end-end-radius: 0.375rem;
  background: rgb(var(--c-brand));
  color: #fff;
  font-size: 0.9375rem;
  line-height: 1.75;
}

.book-demo__question:empty { visibility: hidden; }

.book-demo__status {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  width: fit-content;
  font-size: 0.8125rem;
  color: rgb(var(--c-slate-500));
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 220ms ease, transform 220ms ease;
}

.book-demo__status i { color: rgb(var(--c-teal-600)); animation: book-demo-pulse 1s ease-in-out infinite; }
.book-demo__status.is-on { opacity: 1; transform: none; }

.book-demo__answer {
  max-width: 94%;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 260ms ease, transform 260ms ease;
}

.book-demo__answer.is-on { opacity: 1; transform: none; }

.book-demo__answer-head {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
  font-size: 0.8125rem;
}

.book-demo__badge {
  padding: 0.125rem 0.5rem;
  border-radius: 999px;
  background: rgb(var(--c-teal-50));
  color: rgb(var(--c-teal-800));
  font-size: 0.6875rem;
  font-weight: 600;
}

.book-demo__answer-text {
  min-height: 3.5rem;
  font-size: 0.9375rem;
  line-height: 2;
  color: rgb(var(--c-slate-700));
}

.book-demo__cite {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.75rem;
  padding: 0.375rem 0.75rem;
  border-radius: 0.75rem;
  background: rgb(var(--c-mist));
  font-size: 0.75rem;
  color: rgb(var(--c-slate-600));
  opacity: 0;
  transform: scale(0.94);
  transition: opacity 260ms ease, transform 320ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

.book-demo__cite i { color: rgb(var(--c-teal-700)); }
.book-demo__cite.is-on { opacity: 1; transform: none; }

.book-demo__chips {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.25rem 1.25rem;
  border-top: 1px solid var(--hairline);
}

.book-demo__chips-label { font-size: 0.75rem; font-weight: 600; color: rgb(var(--c-slate-500)); }

.book-demo__chip {
  padding: 0.5rem 0.875rem;
  border-radius: 999px;
  box-shadow: inset 0 0 0 1px rgb(var(--c-teal-700) / 0.22);
  font-size: 0.75rem;
  font-weight: 600;
  color: rgb(var(--c-teal-800));
  transition: background-color 160ms ease, box-shadow 160ms ease, color 160ms ease;
}

.book-demo__chip:hover { background: rgb(var(--c-teal-50)); }

.book-demo__chip[aria-pressed="true"] {
  background: rgb(var(--c-brand));
  box-shadow: none;
  color: #fff;
}

.book-demo__chip:focus-visible { outline: 3px solid rgb(var(--c-teal-500) / 0.55); outline-offset: 2px; }

/* ── Book page ──────────────────────────────────────────────── */

.book-demo__book {
  margin: 0;
  perspective: 1400px;
  padding-inline-end: 0.875rem; /* room for the stacked pages behind */
}

.book-demo__page {
  --lx: 50%;
  --ly: 35%;
  position: relative;
  overflow: hidden;
  min-height: 25rem;
  padding: 1.75rem 1.75rem 3.25rem;
  border-radius: 0.375rem 1.25rem 1.25rem 0.375rem;
  background:
    linear-gradient(to left, rgb(var(--c-ink) / 0.07), transparent 1.75rem), /* spine shade on the right edge */
    var(--paper);
  text-align: start;
  transform-origin: right center;
  box-shadow:
    0 0 0 1px var(--hairline),
    -6px 6px 0 -1px var(--paper),
    -6px 6px 0 0 var(--hairline),
    -12px 12px 0 -1px var(--paper),
    -12px 12px 0 0 var(--hairline),
    0 40px 70px -36px rgb(0 0 0 / 0.3);
}

/* Reading lamp that follows the cursor. */
.book-demo__page::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(220px circle at var(--lx) var(--ly), var(--lamp), transparent 70%);
  opacity: 0;
  transition: opacity 300ms ease;
  pointer-events: none;
}

.book-demo__page.is-lit::after { opacity: 1; }

.book-demo__page-head {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--hairline);
  font-size: 0.6875rem;
  color: rgb(var(--c-slate-500));
}

.book-demo__page-body h3 {
  margin: 1.25rem 0 0.75rem;
  font-size: 1.125rem;
  font-weight: 700;
  color: rgb(var(--c-ink));
}

.book-demo__page-body p {
  margin-top: 0.75rem;
  font-size: 0.9375rem;
  line-height: 2.1;
  color: var(--ink-soft);
}

.book-demo__page-body mark {
  padding: 0.125rem 0;
  border-radius: 0.25rem;
  color: inherit;
  background-color: transparent;
  background-image: linear-gradient(var(--highlight), var(--highlight));
  background-repeat: no-repeat;
  background-position: right 60%;
  background-size: 0% 72%;
  -webkit-box-decoration-break: clone;
  box-decoration-break: clone;
  transition: background-size 900ms cubic-bezier(0.65, 0, 0.35, 1), color 300ms ease;
}

.book-demo__page-body mark.is-marked {
  background-size: 100% 72%;
  color: rgb(var(--c-ink));
}

.book-demo__page-number {
  position: absolute;
  inset-inline: 0;
  bottom: 1rem;
  text-align: center;
  font-size: 0.75rem;
  font-variant-numeric: tabular-nums;
  color: rgb(var(--c-slate-400));
}

/* A light band sweeps the page while Iqraa "searches" it. */
.book-demo__scan {
  position: absolute;
  inset-inline: 0;
  top: -30%;
  height: 30%;
  background: linear-gradient(to bottom, transparent, rgb(var(--c-signal) / 0.14), transparent);
  opacity: 0;
  pointer-events: none;
}

.book-demo__page.is-scanning .book-demo__scan {
  opacity: 1;
  animation: book-demo-scan 1.1s cubic-bezier(0.45, 0, 0.55, 1) forwards;
}

/* Phones: drop the fixed heights so the question and the page fit on one screen. */
@media (max-width: 899px) {
  .book-demo__chat { min-height: 0; }
  .book-demo__page { min-height: 0; padding: 1.25rem 1.25rem 2.75rem; }
  .book-demo__thread { padding: 1.25rem 1rem 0.75rem; }
}

/* Letters flying from the page to the answer. */
.book-demo__flight {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 5;
}

@keyframes book-demo-scan {
  from { top: -30%; }
  to { top: 100%; }
}

@keyframes book-demo-pulse {
  50% { opacity: 0.35; }
}

@media (prefers-reduced-motion: reduce) {
  .book-demo__status i,
  .book-demo__page.is-scanning .book-demo__scan { animation: none; }
  .book-demo__page-body mark,
  .book-demo__answer,
  .book-demo__cite,
  .book-demo__status { transition: none; }
}