/* ===== 怒涛の演習 practice.css ===== */
:root {
  --pr-primary: #b45309;
  --pr-primary-dark: #92400e;
  --pr-primary-light: #fef3c7;
  --pr-correct: #059669;
  --pr-correct-bg: #ecfdf5;
  --pr-wrong: #dc2626;
  --pr-wrong-bg: #fef2f2;
  --pr-neutral: #475569;
  --pr-border: #e2e8f0;
  --pr-bg: #f8fafc;
  --pr-card: #ffffff;
  --pr-text: #1e293b;
  --pr-sub: #64748b;
  --pr-radius: 14px;
  --pr-shadow: 0 2px 12px rgba(0,0,0,0.08);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Hiragino Sans', 'Noto Sans JP', sans-serif;
  background: var(--pr-bg);
  color: var(--pr-text);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ── Nav ── */
.pr-nav {
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--pr-border);
  padding: 13px 20px;
  position: sticky;
  top: 0;
  z-index: 100;
}
.pr-nav-inner {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
}
.pr-nav-back {
  color: var(--pr-primary);
  text-decoration: none;
  font-weight: 700;
  font-size: 0.9rem;
  white-space: nowrap;
}
.pr-nav-title {
  font-weight: 800;
  font-size: 1rem;
  color: var(--pr-text);
}

/* ── Hero ── */
.pr-hero {
  background: linear-gradient(135deg, #78350f 0%, #b45309 100%);
  color: #fff;
  padding: 32px 20px 28px;
  text-align: center;
}
.pr-hero h1 {
  font-size: 1.5rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  margin-bottom: 6px;
}
.pr-hero p {
  font-size: 0.88rem;
  opacity: 0.88;
  line-height: 1.5;
}

/* ── Main layout ── */
.pr-main {
  max-width: 720px;
  margin: 0 auto;
  padding: 20px 16px 80px;
}

/* ── Stats card ── */
.pr-stats-card {
  background: var(--pr-card);
  border-radius: var(--pr-radius);
  box-shadow: var(--pr-shadow);
  padding: 18px 20px;
  margin-bottom: 16px;
  border: 1px solid var(--pr-border);
}
.pr-stats-card h2 {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--pr-sub);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.pr-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}
@media (max-width: 400px) {
  .pr-stats-grid { grid-template-columns: repeat(2, 1fr); }
}
.pr-stat-item {
  text-align: center;
  padding: 10px 6px;
  background: var(--pr-bg);
  border-radius: 10px;
}
.pr-stat-num {
  display: block;
  font-size: 1.4rem;
  font-weight: 900;
  color: var(--pr-primary);
  line-height: 1;
  margin-bottom: 4px;
}
.pr-stat-lbl {
  font-size: 0.72rem;
  color: var(--pr-sub);
  font-weight: 600;
}

/* overall progress bar */
.pr-prog-wrap {
  margin-top: 14px;
  background: #e2e8f0;
  border-radius: 6px;
  height: 8px;
  overflow: hidden;
}
.pr-prog-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--pr-primary), #d97706);
  border-radius: 6px;
  transition: width 0.4s ease;
}
.pr-prog-label {
  font-size: 0.75rem;
  color: var(--pr-sub);
  margin-top: 5px;
  text-align: right;
}

/* ── Filter controls ── */
.pr-controls {
  background: var(--pr-card);
  border-radius: var(--pr-radius);
  box-shadow: var(--pr-shadow);
  padding: 16px 18px;
  margin-bottom: 16px;
  border: 1px solid var(--pr-border);
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.pr-ctrl-label {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--pr-sub);
  margin-bottom: 6px;
  display: block;
}
.pr-filter-row {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding-bottom: 2px;
}
.pr-filter-row::-webkit-scrollbar { display: none; }
.pr-filter-btn {
  flex: 0 0 auto;
  padding: 7px 14px;
  border-radius: 20px;
  border: 1.5px solid var(--pr-border);
  background: #fff;
  color: var(--pr-neutral);
  font-size: 0.8rem;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
}
.pr-filter-btn.active {
  background: var(--pr-primary);
  color: #fff;
  border-color: var(--pr-primary);
}

/* ── Mode buttons ── */
.pr-mode-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}
.pr-mode-btn {
  padding: 10px 8px;
  border-radius: 10px;
  border: 1.5px solid var(--pr-border);
  background: #fff;
  color: var(--pr-neutral);
  font-size: 0.78rem;
  font-weight: 700;
  cursor: pointer;
  text-align: center;
  line-height: 1.3;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
}
.pr-mode-btn.active {
  background: var(--pr-primary);
  color: #fff;
  border-color: var(--pr-primary);
}
.pr-mode-btn .mode-icon { display: block; font-size: 1.1em; margin-bottom: 2px; }

/* ── Start button ── */
.pr-start-btn {
  display: block;
  width: 100%;
  padding: 15px;
  background: linear-gradient(135deg, var(--pr-primary), var(--pr-primary-dark));
  color: #fff;
  font-size: 1rem;
  font-weight: 800;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  letter-spacing: 0.02em;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  box-shadow: 0 3px 10px rgba(180,83,9,0.3);
}
.pr-start-btn:active { transform: scale(0.98); }

/* ── Question screen ── */
.pr-question-screen { display: none; }
.pr-question-screen.active { display: block; }
.pr-setup-screen { display: block; }
.pr-setup-screen.hidden { display: none; }

.pr-q-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}
.pr-q-counter {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--pr-sub);
}
.pr-q-badges {
  display: flex;
  gap: 6px;
}
.pr-badge {
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 0.72rem;
  font-weight: 700;
}
.pr-badge-cat { background: var(--pr-primary-light); color: var(--pr-primary-dark); }
.pr-badge-diff { background: #e0f2fe; color: #0369a1; }

/* Question card */
.pr-q-card {
  background: var(--pr-card);
  border-radius: var(--pr-radius);
  box-shadow: var(--pr-shadow);
  padding: 22px 20px;
  margin-bottom: 14px;
  border: 1px solid var(--pr-border);
}
.pr-q-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--pr-primary);
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.pr-q-text {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--pr-text);
  line-height: 1.65;
}

/* Choices */
.pr-choices {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 14px;
}
.pr-choice-btn {
  width: 100%;
  padding: 14px 16px;
  border-radius: 12px;
  border: 2px solid var(--pr-border);
  background: var(--pr-card);
  color: var(--pr-text);
  font-size: 0.9rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  line-height: 1.5;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  word-break: break-all;
}
.pr-choice-btn:hover:not(:disabled) {
  border-color: var(--pr-primary);
  background: var(--pr-primary-light);
}
.pr-choice-btn.correct {
  border-color: var(--pr-correct);
  background: var(--pr-correct-bg);
  color: #065f46;
}
.pr-choice-btn.wrong {
  border-color: var(--pr-wrong);
  background: var(--pr-wrong-bg);
  color: #991b1b;
}
.pr-choice-btn:disabled { cursor: default; }

/* Result area */
.pr-result {
  display: none;
  border-radius: var(--pr-radius);
  padding: 18px 20px;
  margin-bottom: 14px;
  border-width: 2px;
  border-style: solid;
}
.pr-result.show { display: block; }
.pr-result.correct {
  background: var(--pr-correct-bg);
  border-color: var(--pr-correct);
}
.pr-result.wrong {
  background: var(--pr-wrong-bg);
  border-color: var(--pr-wrong);
}
.pr-result-label {
  font-size: 1.05rem;
  font-weight: 900;
  margin-bottom: 8px;
}
.pr-result.correct .pr-result-label { color: var(--pr-correct); }
.pr-result.wrong .pr-result-label { color: var(--pr-wrong); }
.pr-result-exp {
  font-size: 0.88rem;
  line-height: 1.65;
  color: var(--pr-text);
}
.pr-result-answer {
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 6px;
  padding: 8px 12px;
  background: rgba(255,255,255,0.7);
  border-radius: 8px;
}

/* Action buttons */
.pr-actions {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
}
.pr-btn-next {
  flex: 1;
  padding: 15px;
  background: var(--pr-primary);
  color: #fff;
  font-size: 1rem;
  font-weight: 800;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
}
.pr-btn-next:active { transform: scale(0.98); }
.pr-btn-restart {
  padding: 15px 18px;
  background: #fff;
  color: var(--pr-neutral);
  font-size: 0.88rem;
  font-weight: 700;
  border: 1.5px solid var(--pr-border);
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
  white-space: nowrap;
}

/* Session progress */
.pr-session-prog {
  background: var(--pr-card);
  border-radius: 10px;
  padding: 12px 16px;
  margin-bottom: 14px;
  border: 1px solid var(--pr-border);
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--pr-sub);
}
.pr-sess-bar-wrap {
  flex: 1;
  background: #e2e8f0;
  border-radius: 4px;
  height: 6px;
  overflow: hidden;
}
.pr-sess-bar {
  height: 100%;
  background: var(--pr-primary);
  border-radius: 4px;
  transition: width 0.3s ease;
}

/* Finish screen */
.pr-finish-screen {
  display: none;
  text-align: center;
  padding: 32px 20px;
}
.pr-finish-screen.active { display: block; }
.pr-finish-icon { font-size: 3rem; margin-bottom: 12px; }
.pr-finish-screen h2 {
  font-size: 1.4rem;
  font-weight: 900;
  margin-bottom: 8px;
}
.pr-finish-stats {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 10px;
  margin: 20px 0;
}
.pr-finish-stat {
  background: var(--pr-card);
  border-radius: 12px;
  padding: 14px 8px;
  border: 1px solid var(--pr-border);
}
.pr-finish-stat .num {
  display: block;
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--pr-primary);
}
.pr-finish-stat .lbl {
  font-size: 0.72rem;
  color: var(--pr-sub);
  font-weight: 600;
}
.pr-finish-btns {
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-width: 320px;
  margin: 0 auto;
}
.pr-btn-primary {
  padding: 15px;
  background: var(--pr-primary);
  color: #fff;
  font-size: 1rem;
  font-weight: 800;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
}
.pr-btn-secondary {
  padding: 13px;
  background: #fff;
  color: var(--pr-neutral);
  font-size: 0.9rem;
  font-weight: 700;
  border: 1.5px solid var(--pr-border);
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.15s;
  -webkit-tap-highlight-color: transparent;
}

/* empty state */
.pr-empty {
  text-align: center;
  padding: 40px 20px;
  color: var(--pr-sub);
  font-weight: 600;
}

/* footer */
.pr-footer {
  padding: 36px 0;
  border-top: 1px solid var(--pr-border);
  background: rgba(255,255,255,0.6);
  margin-top: 32px;
}
.pr-footer-inner {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 20px;
  text-align: center;
  font-size: 0.75rem;
  color: #94a3b8;
}