/* ==========================================================================
   IMMERSION — discovery reader
   Ref: handoff § Phase 5.
   ========================================================================== */

:root { --imm-reader-size: 14px; }

.imm-reader-body {
  margin: 0;
  background: var(--imm-canvas-2);
  color: var(--imm-body);
}

.imm-reader {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}

/* --- Sub-header ----------------------------------------------------------- */

.imm-reader__bar {
  display: flex;
  align-items: center;
  gap: var(--imm-s-5);
  padding: var(--imm-s-3) var(--imm-s-9);
  background: var(--imm-paper);
  border-bottom: 1px solid var(--imm-line);
}

.imm-reader__back {
  color: var(--imm-muted);
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}

.imm-reader__back:hover { color: var(--imm-link); }

.imm-reader__title {
  flex: 1;
  min-width: 0;
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  color: var(--imm-text);
}

.imm-reader__range {
  margin-left: var(--imm-s-2);
  font-size: 12.5px;
  font-weight: 400;
  color: var(--imm-faint);
}

.imm-reader__tools {
  display: flex;
  align-items: center;
  gap: var(--imm-s-2);
}

.imm-reader__size {
  min-width: 34px;
  padding: 8px 10px;
  background: var(--imm-paper);
  border: 1px solid var(--imm-line);
  border-radius: var(--imm-r-nav);
  color: var(--imm-text);
  font-size: 13.5px;
  font-weight: 700;
  cursor: pointer;
}

.imm-reader__size:hover { border-color: var(--imm-line-2); color: var(--imm-link); }

/* --- Layout --------------------------------------------------------------- */

.imm-reader__grid {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr var(--imm-rail-reader);
  gap: var(--imm-s-7);
  padding: var(--imm-s-7) var(--imm-s-9);
  align-items: start;
}

.imm-reader__desk { min-width: 0; }

/* --- Page nav ------------------------------------------------------------- */

.imm-reader__nav {
  display: flex;
  align-items: center;
  gap: var(--imm-s-4);
  margin-bottom: var(--imm-s-5);
}

.imm-reader__position {
  flex: 1;
  margin: 0;
  text-align: center;
  font-size: 13px;
  color: var(--imm-faint);
}

.imm-btn[disabled] { opacity: .45; cursor: default; }

/* --- The page sheet ------------------------------------------------------- */

.imm-page { display: none; }
.imm-page.is-visible { display: block; }

.imm-page__text {
  margin: 0;
  padding: 56px 72px;
  background: var(--imm-paper);
  border: 1px solid var(--imm-line-2);
  border-radius: var(--imm-r-page);
  /* The only shadow in the system — the handoff calls the page sheet out as
     the sole exception to flat cards. */
  box-shadow: var(--imm-shadow-page);
  font-family: var(--imm-font-script);
  font-size: var(--imm-reader-size);
  line-height: 1.85;
  white-space: pre-wrap;
  overflow-wrap: break-word;
  color: var(--imm-text);
}

.imm-page__number {
  margin: var(--imm-s-2) 0 0;
  text-align: right;
  font-size: 12.5px;
  color: var(--imm-faint);
}

/* --- Rail ----------------------------------------------------------------- */

.imm-reader__rail {
  display: grid;
  gap: var(--imm-s-4);
  position: sticky;
  top: var(--imm-s-5);
}

.imm-reader__card {
  padding: var(--imm-s-7);
  background: var(--imm-paper);
  border: 1px solid var(--imm-line);
  border-radius: var(--imm-r-card);
}

/* Your notes take the red wash; Karel's take the teal one. That pairing is
   used consistently — red is the student's own mark, teal is Karel's voice. */
.imm-label--mine  { color: var(--imm-red); }
.imm-label--karel { color: var(--imm-link); }

.imm-reader__card--karel {
  background: var(--imm-teal-wash);
  border-color: var(--imm-teal-wash-line);
}

.imm-reader__notes { margin: var(--imm-s-3) 0; }

.imm-note {
  padding: var(--imm-s-4);
  background: var(--imm-red-wash);
  border-left: 3px solid var(--imm-red);
  border-radius: 0 var(--imm-r-nav) var(--imm-r-nav) 0;
}

.imm-reader__card--karel .imm-note__text {
  padding: 0;
  background: none;
  border: 0;
}

.imm-note__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--imm-body);
}

.imm-note__delete {
  margin-top: var(--imm-s-2);
  padding: 0;
  background: none;
  border: 0;
  color: var(--imm-faint);
  font-size: 12.5px;
  text-decoration: underline;
  cursor: pointer;
}

.imm-note__delete:hover { color: var(--imm-red); }

.imm-reader__empty { margin: 0; font-size: 13.5px; color: var(--imm-faint); }

.imm-reader__card textarea {
  margin-bottom: var(--imm-s-3);
  font-size: 14px;
}

.imm-reader__status {
  min-height: 1.2em;
  margin: var(--imm-s-2) 0 0;
  font-size: 12.5px;
  color: var(--imm-faint);
}

.imm-reader__status.is-saved { color: var(--imm-link); }
.imm-reader__status.is-warn,
.imm-reader__status.is-error { color: var(--imm-red); }

/* --- Jump to -------------------------------------------------------------- */

.imm-reader__jump {
  margin: var(--imm-s-3) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 2px;
}

.imm-jump__item {
  display: flex;
  align-items: center;
  gap: var(--imm-s-2);
}

.imm-jump__dot {
  flex: none;
  width: 8px;
  height: 8px;
  border-radius: var(--imm-r-pill);
  background: var(--imm-line-dashed);
}

.imm-jump__dot.has-mine  { background: var(--imm-red); }
.imm-jump__dot.has-karel { background: var(--imm-teal); }

.imm-jump__link {
  padding: 4px 0;
  background: none;
  border: 0;
  color: var(--imm-muted);
  font-size: 13.5px;
  text-align: left;
  cursor: pointer;
}

.imm-jump__link:hover { color: var(--imm-link); }
.imm-jump__item.is-current .imm-jump__link { color: var(--imm-text); font-weight: 700; }

.imm-reader__feed {
  margin: 0;
  font-size: 13px;
  color: var(--imm-faint);
}

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

@media (max-width: 900px) {
  .imm-reader__grid {
    grid-template-columns: 1fr;
    padding: var(--imm-s-5);
  }

  .imm-reader__rail { position: static; }

  .imm-reader__bar {
    flex-wrap: wrap;
    padding: var(--imm-s-3) var(--imm-s-5);
  }

  .imm-reader__tools { width: 100%; }

  .imm-page__text { padding: var(--imm-s-9) var(--imm-s-7); }

  .imm-reader__size,
  .imm-reader__tools .imm-btn { min-height: 44px; }
}

/* --- PDF fallback -----------------------------------------------------------
   Shown only when a step has a PDF but no converted text. The converted text is
   the better reading experience in every way that matters here — it follows the
   theme, reflows, can be selected, and notes can anchor to it — so this exists
   for the cases where conversion is not possible (a scan, or a layout worth
   preserving exactly).
   -------------------------------------------------------------------------- */

.imm-page--pdf { padding: 0; }

.imm-page__pdf {
  display: block;
  width: 100%;
  height: min(80vh, 1000px);
  border: 0;
  border-radius: var(--imm-r-panel);
  background: var(--imm-canvas-2);
}

.imm-page__pdf-fallback {
  padding: var(--imm-s-9);
  text-align: center;
  color: var(--imm-body);
}

.imm-page__pdf-fallback p { margin: 0 0 var(--imm-s-5); }

@media (max-width: 780px) {
  /* iOS will not scroll a PDF inside a short box, so it gets the full screen. */
  .imm-page__pdf { height: 70vh; }
}