/* ============================================================
 * chapter.css — per-beat page: branches, marks, decision cards
 * ============================================================ */

/* --- Reading note (intro paragraph above article) ---------- */

.reading-note {
  max-width: var(--max-text);
  margin: 0 auto 4rem;
  font-style: italic;
  font-size: 0.92rem;
  color: var(--ink-soft);
  line-height: 1.7;
  text-align: center;
  padding: 0 1rem;
}
.reading-note .key-mark {
  display: inline-block;
  width: 2px;
  height: 0.95em;
  background: var(--branch);
  vertical-align: -0.05em;
  margin: 0 0.15em;
}

/* --- Beat structure ---------------------------------------- */

.beat { margin-bottom: 5rem; }

.beat-header {
  text-align: center;
  margin: 3rem 0 3rem;
}

.beat-title {
  font-family: var(--serif);
  font-weight: 400;
  font-style: italic;
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  margin-bottom: 0.4rem;
  color: var(--ink);
}

.beat-subtitle {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 0.5rem;
}

.beat-dateline {
  font-style: italic;
  font-size: 0.85rem;
  color: var(--ink-faint);
}

/* --- Section --------------------------------------------- */

.section {
  margin-bottom: 4.5rem;
  position: relative;
}

.section-mark {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  color: var(--ink-faint);
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  text-align: center;
}
.section-mark::before,
.section-mark::after {
  content: "\2014";
  margin: 0 0.8rem;
  color: var(--branch-faint);
}

/* --- Drop cap (first paragraph of each beat) ---------------
   Wrapped in <span class="drop-cap"> at build time so we have
   reliable CSS control (::first-letter has uneven animation
   support across browsers). We animate color + transform: scale
   in a clearly visible curve. */

.drop-cap {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 3.4rem;
  line-height: 0.9;
  float: left;
  padding: 0.4rem 0.55rem 0 0;
  display: inline-block;
  color: var(--ink);
  transform: scale(1);
  transform-origin: bottom left;
  animation: drop-cap-in 1800ms cubic-bezier(0.32, 0.72, 0.24, 1) 500ms both;
}

@keyframes drop-cap-in {
  0%   { color: var(--branch); transform: scale(0.7); opacity: 0.4; }
  35%  { color: var(--branch); }
  100% { color: var(--ink);    transform: scale(1);   opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .drop-cap { animation: none; }
}

/* --- Fork paragraph + branch mark -------------------------- */

.fork-paragraph { position: relative; }

.branch-mark {
  position: absolute;
  right: -2.8rem;
  top: 0.45rem;
  width: 2rem;
  height: 100%;
  cursor: pointer;
  display: flex;
  align-items: flex-start;
  padding-top: 0.3em;
  z-index: 5;
  background: transparent;
  border: none;
  font-family: var(--mono);
  /* Animate the button itself for reveal-on-scroll. */
  opacity: 1;
  transform: translateX(0) scale(1);
  transform-origin: left center;
  transition:
    opacity 1000ms cubic-bezier(0.32, 0.72, 0.24, 1),
    transform 800ms cubic-bezier(0.32, 0.72, 0.24, 1);
}

.branch-mark::before {
  content: "";
  display: block;
  width: 1px;
  height: 2.8em;
  background: var(--branch);
  transition: width 200ms ease, height 200ms ease, background-color 200ms ease;
}

/* Reveal-on-scroll: chapter.js sets .mark-pending on each fork
   paragraph at init, and removes it as the paragraph enters the
   viewport. Resting state below; revealed state is the default
   above. */
.fork-paragraph.mark-pending .branch-mark {
  opacity: 0;
  transform: translateX(-12px) scale(0.6);
}
.fork-paragraph.mark-pending .branch-mark .label {
  opacity: 0 !important;
}

.branch-mark:hover::before,
.branch-mark:focus::before {
  width: 2px;
  height: 3.4em;
}

.branch-mark .label {
  position: absolute;
  left: 1.2rem;
  top: 0.4em;
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--branch);
  white-space: nowrap;
  opacity: 0;
  transition: opacity 240ms ease;
  pointer-events: none;
}

.branch-mark:hover .label,
.branch-mark:focus .label { opacity: 1; }

.branch-mark:focus-visible {
  outline: 2px solid var(--branch);
  outline-offset: 4px;
  border-radius: 1px;
}
.branch-mark:focus { outline: none; }

/* On a branch, dim other forks; hide the active one */
body.branched .branch-mark,
body.animating .branch-mark {
  pointer-events: none;
  opacity: 0.25;
}
body.branched .branch-mark.active-branch {
  opacity: 0;
  display: none;
}

/* --- Decision card ----------------------------------------- */

.decision {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.45s cubic-bezier(0.4, 0, 0.2, 1), margin 0.45s ease;
  margin: 0;
}
.decision.open {
  max-height: 24rem;
  margin: 1.4rem 0 1.6rem;
}

.decision-inner {
  background: var(--paper-deep);
  border-left: 2px solid var(--branch);
  padding: 1.4rem 1.6rem;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 280ms cubic-bezier(0.4, 0, 0.2, 1) 100ms,
              transform 280ms cubic-bezier(0.4, 0, 0.2, 1) 100ms;
}
.decision.open .decision-inner {
  opacity: 1;
  transform: translateY(0);
}

.decision-title {
  font-family: var(--mono);
  font-size: 0.65rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--branch);
  font-weight: 500;
  margin-bottom: 0.7rem;
}

.decision-summary {
  font-style: italic;
  color: var(--ink-soft);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 1.2rem;
}

.decision-actions {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
}

.decision-btn {
  background: none;
  border: 1px solid var(--ink-soft);
  color: var(--ink-soft);
  font-family: var(--mono);
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  padding: 0.6rem 1rem;
  cursor: pointer;
  transition: background-color 200ms ease, color 200ms ease, border-color 200ms ease;
  border-radius: 1px;
}
.decision-btn:hover {
  background: var(--ink);
  color: var(--paper);
  border-color: var(--ink);
}
.decision-btn.primary {
  border-color: var(--branch);
  color: var(--branch);
}
.decision-btn.primary:hover {
  background: var(--branch);
  color: var(--paper);
  border-color: var(--branch);
}

/* --- Multi-section runtime fix (hide canon sections branch
       does not replace; restore on return-to-canon). ----------- */

.hidden-by-branch { display: none; }

/* --- Post-fork wrapper (canon + branch share this slot) ---- */

.post-fork { position: relative; }

body.branched .post-fork {
  border-left: 2px solid var(--branch);
  padding-left: 1.2rem;
  margin-left: -1.4rem;
  transition: border-color 800ms ease;
}

/* --- Branch-coda block (the italic anomaly-log entry) ------
   Renders as a single light-shaded box. Consecutive coda paragraphs
   share the same background and merge visually; the build marks the
   first coda with .coda-first (top padding) and the last with
   .coda-last (bottom padding) to preserve the box look without
   needing to wrap them in a parent (which would break the split-flap
   rewrite, which only animates direct <p> children).
   ----------------------------------------------------------- */

.branch-coda-line {
  font-family: var(--mono);
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--ink-soft);
  font-style: normal;
  background: var(--paper-deep);
  padding: 0.4rem 1.6rem;
  margin: 0;
  border-left: 2px solid var(--branch-faint);
}

.branch-coda-line.coda-first {
  padding-top: 1.4rem;
  margin-top: 2.4rem;
}

.branch-coda-line.coda-last {
  padding-bottom: 1.4rem;
  margin-bottom: 1.5rem;
}

.branch-coda-line em {
  font-style: italic;
  color: var(--ink);
}

/* --- Return-to-canon button -------------------------------- */

.return-to-canon {
  display: none;
  margin-top: 1.2rem;
  background: none;
  border: 1px solid var(--branch);
  color: var(--branch);
  font-family: var(--mono);
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  padding: 0.55rem 1.1rem;
  cursor: pointer;
  transition: background-color 200ms ease, color 200ms ease;
  border-radius: 1px;
}
body.branched .return-to-canon { display: inline-block; }
.return-to-canon:hover { background: var(--branch); color: var(--paper); }
.return-to-canon:disabled { opacity: 0.5; cursor: wait; }

/* --- Rewriting pulse (shown during animation) -------------- */

.rewriting-pulse {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--mono);
  font-size: 0.65rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--branch);
  opacity: 0;
  transition: opacity 0.4s;
  z-index: 100;
  background: var(--paper);
  padding: 0.5rem 1rem;
  border: 1px solid var(--branch);
  border-radius: 1px;
}
.rewriting-pulse.show { opacity: 1; }
.rewriting-pulse .dot {
  display: inline-block;
  width: 4px;
  height: 4px;
  background: var(--branch);
  border-radius: 50%;
  margin-left: 0.4rem;
  animation: pulse 1.2s infinite;
}

/* --- 11ms timestamp Easter egg ----------------------------- */

.coda-tick {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  font-family: var(--mono);
  font-size: 0.6rem;
  letter-spacing: 0.18em;
  color: var(--branch-faint);
  opacity: 0;
  z-index: 50;
  pointer-events: none;
}
.coda-tick.show {
  animation: coda-tick-in 1.4s ease-out;
}

/* --- Mobile ------------------------------------------------ */

@media (max-width: 720px) {
  .section { margin-bottom: 3.5rem; }
  /* On portrait phones the article fills the viewport minus the
     container's 1.5rem left padding. The mark sits inside that
     padding (between the viewport edge and the paragraph's first
     character) — left: -1rem of paragraph means it appears at
     0.5rem from the viewport edge, comfortably visible. */
  .branch-mark {
    right: auto;
    left: -1.1rem;
    width: 1rem;
  }
  .branch-mark .label {
    left: 1.4rem;     /* inside the paragraph if it appears */
    top: 0.4em;
  }
  body.branched .post-fork { margin-left: -0.8rem; padding-left: 0.6rem; }
}

/* Very narrow phones — give the mark a touch more room. */
@media (max-width: 380px) {
  .branch-mark { left: -0.9rem; width: 0.9rem; }
}