/* =====================================================================
   MOTION v8 — reveal + hairline + chapter marker
   ===================================================================== */

/* Reveal padrão (R02 manual 005) */
[data-reveal] {
  opacity: 0;
  transform: translate3d(0, 28px, 0);
  transition:
    opacity var(--dur-reveal) var(--ease-out),
    transform var(--dur-reveal) var(--ease-out);
  transition-delay: calc(var(--reveal-delay, 0) * var(--stagger));
}
[data-reveal].is-visible { opacity: 1; transform: none; }

/* Reveal inline (parágrafos) */
[data-reveal-inline] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity var(--dur-ui) var(--ease-out), transform var(--dur-ui) var(--ease-out);
  transition-delay: calc(var(--reveal-delay, 0) * var(--stagger));
}
[data-reveal-inline].is-visible { opacity: 1; transform: none; }

/* Reveal com máscara lateral (R02 para títulos) */
[data-reveal-mask] {
  opacity: 0;
  clip-path: inset(0 100% 0 0);
  transition:
    opacity var(--dur-cinema) var(--ease-out),
    clip-path var(--dur-cinema) var(--ease-out);
}
[data-reveal-mask].is-visible {
  opacity: 1;
  clip-path: inset(0 0 0 0);
}

/* Chapter marker (numeração vertical tipo índice de livro) */
.chapter-marker {
  position: relative;
  padding-left: 0;
  margin-bottom: var(--s-8);
  display: flex;
  align-items: baseline;
  gap: var(--s-4);
}
.chapter-marker__num {
  font-family: var(--f-mono);
  font-size: var(--fs-xs);
  font-weight: 500;
  letter-spacing: .24em;
  color: var(--c-purple);
  text-transform: uppercase;
}
.chapter-marker__line {
  flex: 1;
  height: 1px;
  background: var(--c-purple-line);
  position: relative;
  overflow: hidden;
  transform-origin: left;
  transform: scaleX(0);
  transition: transform 1200ms var(--ease-out) 200ms;
}
.chapter-marker__line.is-visible { transform: scaleX(1); }
.chapter-marker__label {
  font-family: var(--f-mono);
  font-size: var(--fs-xs);
  font-weight: 500;
  letter-spacing: .28em;
  text-transform: uppercase;
  color: var(--c-gray-light);
}

/* Hairline com animação */
.hairline {
  height: 1px;
  background: var(--c-border);
  border: 0;
  margin: var(--s-12) 0;
  position: relative;
  overflow: hidden;
}
.hairline::after {
  content: "";
  position: absolute;
  top: 0; left: 0;
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, transparent, var(--c-purple), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur-cinema) var(--ease-out);
}
.hairline.is-visible::after { transform: scaleX(1); }

/* Skip link */
.skip-link {
  position: absolute; left: 8px; top: -100px;
  background: var(--c-purple); color: var(--c-paper);
  padding: var(--s-2) var(--s-4); z-index: 100;
  transition: top var(--dur-ui) var(--ease-std);
  font-family: var(--f-body);
  font-weight: 600;
  text-decoration: none;
}
.skip-link:focus { top: 8px; }

.visually-hidden {
  position: absolute; width: 1px; height: 1px;
  margin: -1px; padding: 0; overflow: hidden;
  clip: rect(0,0,0,0); border: 0;
}