/* ============================================================
   Capsule IASE — Scroll-Driven Visual Reading
   ============================================================ */

/* ── CSS fallback: backdrop for non-WebGL2 browsers ── */
#capsule-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

#capsule-backdrop img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 0.8s ease-out;
  will-change: opacity;
}

#capsule-backdrop img.capsule-active {
  opacity: 1;
}

/* ── Text overlay in capsule mode ── */
.capsule-mode #reader-content {
  position: relative;
  z-index: 1;
  background: linear-gradient(
    180deg,
    color-mix(in srgb, var(--color-bg-base) 85%, transparent) 0%,
    color-mix(in srgb, var(--color-bg-base) 92%, transparent) 50%,
    color-mix(in srgb, var(--color-bg-base) 85%, transparent) 100%
  );
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

/* ── Progress bar (thin, below nav) ── */
#capsule-progress {
  position: fixed;
  top: 3.5rem;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 100;
  background: transparent;
  pointer-events: none;
}

#capsule-progress-fill {
  height: 100%;
  background: var(--color-accent);
  width: 0%;
  transition: width 0.15s linear;
  border-radius: 0 1px 1px 0;
}

/* ── Audio toggle ── */
#capsule-audio-toggle {
  position: fixed;
  top: 4.5rem;
  right: 1.5rem;
  z-index: 51;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  background: color-mix(in srgb, var(--color-bg-base) 80%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all 0.2s;
}

#capsule-audio-toggle:hover {
  border-color: var(--color-accent-muted);
  color: var(--color-accent);
}

#capsule-audio-toggle.playing {
  border-color: var(--color-accent);
  color: var(--color-accent);
  box-shadow: 0 0 12px rgba(0, 212, 170, 0.2);
}

/* ── Capsule Loading Screen ── */
#capsule-loading {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--color-bg-base);
  transition: opacity 0.4s ease;
}

#capsule-loading.fade-out {
  opacity: 0;
  pointer-events: none;
}

#capsule-loading .loading-icon {
  width: 3rem;
  height: 3rem;
  margin-bottom: 1.5rem;
  border: 2px solid var(--color-border);
  border-top-color: var(--color-accent);
  border-radius: 50%;
  animation: capsule-spin 0.8s linear infinite;
}

@keyframes capsule-spin {
  to { transform: rotate(360deg); }
}

#capsule-loading .loading-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 0.5rem;
}

#capsule-loading .loading-stage {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: 1.5rem;
  min-height: 1.25rem;
}

#capsule-loading .loading-bar {
  width: min(20rem, 80vw);
  height: 4px;
  background: var(--color-bg-surface);
  border-radius: 2px;
  overflow: hidden;
}

#capsule-loading .loading-bar-fill {
  height: 100%;
  background: var(--color-accent);
  width: 0%;
  border-radius: 2px;
  transition: width 0.3s ease;
}

/* ── Mobile ── */
@media (max-width: 640px) {
  .capsule-mode #reader-content {
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    background: color-mix(in srgb, var(--color-bg-base) 90%, transparent);
  }

  #capsule-audio-toggle {
    top: auto;
    bottom: 5rem;
    right: 1rem;
  }
}

/* Attempt-first recall. Covers the passage until the reader submits. */
#recall-overlay {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  background: color-mix(in srgb, var(--color-bg-base) 96%, transparent);
}

#recall-overlay[hidden] {
  display: none;
}

#recall-overlay [hidden] {
  display: none;
}

#recall-overlay .recall-card {
  width: min(36rem, 100%);
  background: var(--color-bg-surface, var(--color-bg-base));
  color: var(--color-text-body);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.28);
}

#recall-overlay h2 {
  margin: 0 0 0.75rem;
  font-size: 1.25rem;
}

#recall-overlay p {
  margin: 0 0 0.75rem;
  line-height: 1.5;
}

#recall-overlay textarea {
  width: 100%;
  min-height: 8rem;
  margin: 0.5rem 0 1rem;
  padding: 0.75rem;
  font: inherit;
  color: inherit;
  background: var(--color-bg-base);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  resize: vertical;
}

#recall-overlay .recall-label {
  display: block;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

#recall-overlay .recall-actions {
  display: flex;
  gap: 0.75rem;
}

#recall-overlay button {
  font: inherit;
  cursor: pointer;
  border-radius: 8px;
  padding: 0.55rem 0.9rem;
  border: 1px solid var(--color-border);
  background: transparent;
  color: inherit;
}

#recall-overlay #recall-submit,
#recall-overlay #recall-close {
  background: var(--color-accent);
  color: var(--color-bg-base, #111);
  border-color: transparent;
}

#recall-overlay #recall-hint-btn {
  margin-bottom: 0.75rem;
}

#recall-overlay blockquote {
  margin: 0 0 1rem;
  padding-left: 0.75rem;
  border-left: 3px solid var(--color-accent);
}

#recall-overlay .recall-error {
  color: var(--color-danger, #c44);
  margin-top: 0.75rem;
}