/*
  /phrasebook/engine.css
  Shared SRS Phrasebook Engine — styles
  Used by: Interview, Sherlock Holmes, and any future course.
  All selectors are prefixed .pb- to avoid conflicts with host CSS.
*/

/* ── Root colours (independent of host CSS) ───────────────────── */
.pb-root {
  --pb-navy:   #1a2744;
  --pb-gold:   #c9a227;
  --pb-gold2:  #b08f22;
  --pb-muted:  #8a7e6e;
  --pb-red:    #e05252;
  --pb-green:  #2ecc71;
  --pb-orange: #f0932b;
  --pb-bg:     #f5f0e8;
  --pb-line:   #e8e2d9;
}

/* ── Page wrap ─────────────────────────────────────────────────── */
.pb-wrap {
  max-width: 780px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 4rem;
}

/* ── Hero ──────────────────────────────────────────────────────── */
.pb-hero { text-align: center; padding: 2rem 0 1.25rem; }
.pb-hero h1 {
  font-family: 'Playfair Display', serif;
  font-size: 2rem;
  color: var(--pb-navy);
  margin: 0 0 0.25rem;
}
.pb-hero p { font-size: 0.9rem; color: var(--pb-muted); margin: 0; }

/* ── Stats ─────────────────────────────────────────────────────── */
.pb-stats {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin: 1.25rem 0;
}
.pb-stat {
  background: #fff;
  border: 1px solid var(--pb-line);
  border-radius: 12px;
  padding: 0.75rem 1.25rem;
  text-align: center;
  min-width: 90px;
}
.pb-stat-n {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--pb-navy);
  line-height: 1;
}
.pb-stat-l {
  font-size: 0.7rem;
  color: var(--pb-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-top: 0.2rem;
}
.pb-stat.due     .pb-stat-n { color: var(--pb-red); }
.pb-stat.learned .pb-stat-n { color: #27ae60; }

/* ── Review start buttons ──────────────────────────────────────── */
.pb-actions { text-align: center; margin-bottom: 1.25rem; }
.pb-review-start {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--pb-navy);
  color: #fff;
  padding: 0.85rem 2rem;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
  margin: 0.4rem;
  font-family: inherit;
}
.pb-review-start:hover:not(:disabled) { background: #253660; transform: translateY(-2px); }
.pb-review-start.gold { background: var(--pb-gold); color: var(--pb-navy); }
.pb-review-start.gold:hover:not(:disabled) { background: var(--pb-gold2); }
.pb-review-start:disabled { opacity: 0.4; cursor: not-allowed; }

/* ── Mode selector ─────────────────────────────────────────────── */
.pb-mode-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 1.5rem;
  align-items: center;
}
.pb-mode-label { font-size: 0.78rem; color: var(--pb-muted); }
.pb-mode-btn {
  background: #fff;
  border: 1.5px solid #ddd;
  border-radius: 999px;
  padding: 0.4rem 0.95rem;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
  color: var(--pb-navy);
  font-family: inherit;
}
.pb-mode-btn:hover,
.pb-mode-btn.active {
  border-color: var(--pb-gold);
  background: var(--pb-gold);
  color: var(--pb-navy);
}

/* ── Filter tabs ───────────────────────────────────────────────── */
.pb-filters {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
  border-bottom: 2px solid var(--pb-line);
  padding-bottom: 0.75rem;
}
.pb-filter-btn {
  background: none;
  border: 1.5px solid #ddd;
  border-radius: 999px;
  padding: 0.35rem 0.85rem;
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--pb-muted);
  transition: all 0.15s;
  font-family: inherit;
}
.pb-filter-btn.active { background: var(--pb-navy); color: #fff; border-color: var(--pb-navy); }
.pb-filter-btn:hover:not(.active) { border-color: var(--pb-navy); color: var(--pb-navy); }

/* ── Card grid ─────────────────────────────────────────────────── */
.pb-grid { display: grid; gap: 0.75rem; }
.pb-card {
  background: #fff;
  border: 1px solid var(--pb-line);
  border-radius: 14px;
  padding: 1rem 1.1rem;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.25rem;
  align-items: start;
  transition: box-shadow 0.15s;
}
.pb-card:hover { box-shadow: 0 4px 16px rgba(26,39,68,0.08); }
.pb-card-phrase   { font-weight: 700; color: var(--pb-navy); font-size: 1rem; }
.pb-card-phonetic { font-size: 0.78rem; color: var(--pb-muted); margin-top: 0.1rem; font-style: italic; }
.pb-card-ua       { font-size: 0.85rem; color: #666; margin-top: 0.3rem; }
.pb-card-ctx      { font-size: 0.78rem; color: var(--pb-muted); margin-top: 0.25rem; font-style: italic; }
.pb-card-meta     { display: flex; align-items: center; gap: 0.5rem; margin-top: 0.5rem; flex-wrap: wrap; }
.pb-card-level    { font-size: 0.65rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; padding: 0.15rem 0.5rem; border-radius: 999px; }
.pb-card-level.new      { background: #e8f4fd; color: #2980b9; }
.pb-card-level.learning { background: #fef9e7; color: #d68910; }
.pb-card-level.learned  { background: #eafaf1; color: #27ae60; }
.pb-card-next { font-size: 0.7rem; color: var(--pb-muted); }
.pb-card-src  { font-size: 0.7rem; color: var(--pb-muted); }
.pb-card-actions { display: flex; flex-direction: column; gap: 0.4rem; align-items: flex-end; }
.pb-card-remove {
  background: none; border: none; cursor: pointer;
  color: #ccc; font-size: 1.1rem; line-height: 1;
  transition: color 0.15s; padding: 0;
}
.pb-card-remove:hover { color: var(--pb-red); }
.pb-card-speak {
  background: none; border: none; cursor: pointer;
  color: var(--pb-muted); font-size: 0.9rem;
  padding: 0; transition: color 0.15s;
}
.pb-card-speak:hover { color: var(--pb-navy); }

.pb-empty { text-align: center; padding: 3rem 1rem; color: var(--pb-muted); }
.pb-empty h3 { font-size: 1.1rem; color: var(--pb-navy); margin-bottom: 0.5rem; }
.pb-empty p  { font-size: 0.9rem; margin: 0; }

/* ── Review overlay ────────────────────────────────────────────── */
.pb-review-wrap {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--pb-bg);
  z-index: 9000;
  overflow-y: auto;
  padding: 1.5rem 1rem 3rem;
}
.pb-review-wrap.open { display: block; }

.pb-review-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 600px;
  margin: 0 auto 1.25rem;
}
.pb-review-title { font-weight: 700; color: var(--pb-navy); font-size: 1rem; }
.pb-review-close {
  background: none;
  border: 1.5px solid #ddd;
  border-radius: 999px;
  padding: 0.35rem 0.85rem;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--pb-muted);
  transition: all 0.15s;
  font-family: inherit;
}
.pb-review-close:hover { border-color: var(--pb-navy); color: var(--pb-navy); }

.pb-progress-wrap {
  max-width: 600px;
  margin: 0 auto 1.75rem;
  background: #ddd;
  border-radius: 999px;
  height: 6px;
  overflow: hidden;
}
.pb-progress-fill {
  height: 100%;
  background: var(--pb-gold);
  border-radius: 999px;
  transition: width 0.4s;
  width: 0%;
}

/* ── Exercise card ─────────────────────────────────────────────── */
.pb-exercise {
  max-width: 600px;
  margin: 0 auto;
  background: #fff;
  border-radius: 20px;
  padding: 2rem 1.75rem;
  box-shadow: 0 8px 32px rgba(26,39,68,0.1);
  min-height: 300px;
  display: flex;
  flex-direction: column;
}
.pb-ex-mode-label {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--pb-gold);
  margin-bottom: 1.25rem;
}
.pb-ex-prompt { flex: 1; }
.pb-ex-phrase {
  font-family: 'Playfair Display', serif;
  font-size: 1.4rem;
  color: var(--pb-navy);
  line-height: 1.35;
  margin-bottom: 0.4rem;
}
.pb-ex-sub { font-size: 0.85rem; color: var(--pb-muted); margin-bottom: 0.25rem; }

/* Flip */
.pb-flip-hint {
  margin-top: 1rem;
  border: 1.5px dashed #ddd;
  border-radius: 10px;
  padding: 0.75rem 1rem;
  cursor: pointer;
  text-align: center;
  transition: all 0.2s;
  user-select: none;
  color: var(--pb-muted);
  font-size: 0.85rem;
}
.pb-flip-hint:hover           { border-color: var(--pb-gold); color: var(--pb-navy); }
.pb-flip-hint.revealed        { border-style: solid; border-color: var(--pb-navy); background: #f8f6f0; cursor: default; }
.pb-flip-ua                   { font-size: 1rem; font-weight: 700; color: var(--pb-navy); }
.pb-flip-context              { font-size: 0.78rem; color: #666; margin-top: 0.4rem; font-style: italic; }

/* Choices */
.pb-choices { display: grid; gap: 0.5rem; margin-top: 1rem; }
.pb-choice {
  background: #f8f6f0;
  border: 2px solid var(--pb-line);
  border-radius: 10px;
  padding: 0.75rem 1rem;
  font-size: 0.92rem;
  cursor: pointer;
  transition: all 0.15s;
  text-align: left;
  font-weight: 500;
  color: var(--pb-navy);
  font-family: inherit;
}
.pb-choice:hover:not(:disabled) { border-color: var(--pb-gold); background: #fffbf0; }
.pb-choice.correct { border-color: var(--pb-green); background: #eafaf1; color: #1a7a3c; }
.pb-choice.wrong   { border-color: var(--pb-red);   background: #fdecea; color: #a93226; }

/* Input */
.pb-ex-input {
  width: 100%;
  margin-top: 0.75rem;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  border: 2px solid #ddd;
  border-radius: 10px;
  font-family: 'Inter', sans-serif;
  outline: none;
  transition: border-color 0.15s;
  box-sizing: border-box;
}
.pb-ex-input:focus   { border-color: var(--pb-gold); }
.pb-ex-input.correct { border-color: var(--pb-green); background: #eafaf1; }
.pb-ex-input.wrong   { border-color: var(--pb-red);   background: #fdecea; }
.pb-ex-reveal { font-size: 0.85rem; color: #666; margin-top: 0.5rem; }

/* Audio */
.pb-audio-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--pb-navy);
  color: #fff;
  border: none;
  border-radius: 999px;
  padding: 0.7rem 1.4rem;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 0.75rem;
  transition: all 0.2s;
  font-family: inherit;
}
.pb-audio-btn:hover   { background: #253660; }
.pb-audio-btn.playing { background: var(--pb-gold); color: var(--pb-navy); }

/* Blank */
.pb-blank-wrap  { font-size: 1.1rem; color: var(--pb-navy); margin-top: 0.75rem; line-height: 2.4; }
.pb-blank-input {
  border: none;
  border-bottom: 2.5px solid var(--pb-gold);
  background: transparent;
  font-size: 1.05rem;
  font-family: 'Inter', sans-serif;
  color: var(--pb-navy);
  outline: none;
  padding: 0 4px;
  min-width: 80px;
  text-align: center;
}
.pb-blank-input.correct { border-color: var(--pb-green); color: #27ae60; }
.pb-blank-input.wrong   { border-color: var(--pb-red);   color: var(--pb-red); }

/* Footer buttons */
.pb-ex-footer { margin-top: 1.5rem; }
.pb-check-btn {
  width: 100%;
  padding: 0.85rem;
  background: var(--pb-navy);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  font-family: inherit;
}
.pb-check-btn:hover { background: #253660; }

.pb-grade-row { display: none; gap: 0.5rem; }
.pb-grade-row.visible { display: flex; }
.pb-grade-btn {
  flex: 1;
  padding: 0.85rem 0.5rem;
  border: none;
  border-radius: 12px;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  transition: filter 0.15s;
  font-family: inherit;
}
.pb-grade-btn.fail { background: #fdecea; color: var(--pb-red); }
.pb-grade-btn.hard { background: #fef9e7; color: var(--pb-orange); }
.pb-grade-btn.good { background: #eafaf1; color: #27ae60; }
.pb-grade-btn:hover { filter: brightness(0.93); }

/* Summary */
.pb-summary { max-width: 600px; margin: 2rem auto; text-align: center; display: none; }
.pb-summary h2 {
  font-family: 'Playfair Display', serif;
  font-size: 1.8rem;
  color: var(--pb-navy);
  margin-bottom: 0.5rem;
}
.pb-summary p { color: var(--pb-muted); margin-bottom: 1.5rem; }
.pb-summary-stats {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin: 1.5rem 0;
}
.pb-summary-stat { background: #fff; border-radius: 12px; padding: 0.75rem 1.25rem; text-align: center; }
.pb-summary-n    { font-size: 1.8rem; font-weight: 800; line-height: 1; }
.pb-summary-l    { font-size: 0.7rem; color: var(--pb-muted); text-transform: uppercase; letter-spacing: 0.05em; }
.pb-summary-stat.good  { border: 2px solid var(--pb-green); }
.pb-summary-stat.good  .pb-summary-n { color: #27ae60; }
.pb-summary-stat.fail  { border: 2px solid var(--pb-red); }
.pb-summary-stat.fail  .pb-summary-n { color: var(--pb-red); }
.pb-summary-stat.total { border: 2px solid var(--pb-gold); }
.pb-summary-stat.total .pb-summary-n { color: var(--pb-navy); }