:root {
  color-scheme: light;
  --ink: #14223a;
  --muted: #617087;
  --line: #dce5ed;
  --surface: #ffffff;
  --soft: #f4f8fa;
  --primary: #176b68;
  --primary-dark: #0d4f4c;
  --accent: #e7f5f1;
  --repair: #a54b16;
  --repair-soft: #fff2e8;
  --danger: #9d2f3f;
  font-family: "Yu Gothic UI", "Hiragino Sans", "Meiryo", sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% 4%, rgba(36, 144, 132, 0.12), transparent 28rem),
    linear-gradient(180deg, #f8fbfc 0%, #eef4f6 100%);
}

button,
input { font: inherit; }

button,
a { -webkit-tap-highlight-color: transparent; }

[hidden] { display: none !important; }

.preview-topbar {
  display: grid;
  grid-template-columns: 2.75rem minmax(0, 1fr) auto;
  gap: 0.8rem;
  align-items: center;
  width: min(100%, 64rem);
  margin: 0 auto;
  padding: 1rem clamp(1rem, 4vw, 2rem);
}

.preview-back {
  display: grid;
  place-items: center;
  width: 2.75rem;
  height: 2.75rem;
  border: 1px solid var(--line);
  border-radius: 50%;
  color: var(--ink);
  background: rgba(255,255,255,0.9);
  text-decoration: none;
  font-size: 1.25rem;
}

.preview-heading p {
  margin: 0 0 0.15rem;
  color: var(--primary);
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.preview-heading h1 {
  margin: 0;
  font-size: clamp(1rem, 3vw, 1.35rem);
}

.preview-reset,
.preview-jump-form button {
  border: 1px solid var(--line);
  border-radius: 0.75rem;
  color: var(--ink);
  background: var(--surface);
  padding: 0.7rem 0.9rem;
  cursor: pointer;
}

.preview-main {
  width: min(100%, 48rem);
  margin: 0 auto;
  padding: clamp(1rem, 4vw, 2rem) clamp(1rem, 4vw, 2rem) 4rem;
}

.preview-message {
  margin: 12vh auto 0;
  padding: 2.5rem 1.5rem;
  border: 1px solid var(--line);
  border-radius: 1.5rem;
  background: rgba(255,255,255,0.92);
  text-align: center;
  box-shadow: 0 1.2rem 3rem rgba(28, 52, 68, 0.08);
}

.preview-message h2 { margin: 1rem 0 0.5rem; font-size: 1.25rem; }
.preview-message p { margin: 0; color: var(--muted); line-height: 1.75; }

.preview-spinner {
  display: inline-block;
  width: 2.25rem;
  height: 2.25rem;
  border: 0.25rem solid var(--accent);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: preview-spin 0.8s linear infinite;
}

.preview-message-icon {
  display: grid;
  place-items: center;
  width: 2.5rem;
  height: 2.5rem;
  margin: auto;
  border-radius: 50%;
  color: #fff;
  background: var(--danger);
  font-weight: 900;
}

.preview-primary-link {
  display: inline-block;
  margin-top: 1.25rem;
  border-radius: 0.85rem;
  padding: 0.8rem 1.1rem;
  color: #fff;
  background: var(--primary);
  text-decoration: none;
  font-weight: 700;
}

.preview-progress-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.9rem 1.25rem;
  align-items: end;
  margin-bottom: 1rem;
}

.preview-status-row { display: flex; gap: 0.5rem; flex-wrap: wrap; }

.preview-mode-badge,
.preview-isolation-badge {
  display: inline-flex;
  align-items: center;
  min-height: 1.7rem;
  border-radius: 999px;
  padding: 0.3rem 0.65rem;
  font-size: 0.72rem;
  font-weight: 800;
}

.preview-mode-badge { color: var(--primary-dark); background: var(--accent); }
.preview-isolation-badge { color: #4f5c6c; background: #e9eef2; }
.is-repair .preview-mode-badge { color: var(--repair); background: var(--repair-soft); }
.is-reinforcement .preview-mode-badge { color: #31577a; background: #dcecf8; }

.preview-lesson-label { margin: 0.75rem 0 0.1rem; font-size: 1.35rem; font-weight: 850; }
.preview-position-label { margin: 0; color: var(--muted); font-size: 0.88rem; }

.preview-progress-track {
  grid-column: 1 / -1;
  height: 0.38rem;
  overflow: hidden;
  border-radius: 999px;
  background: #dbe5e9;
}

.preview-progress-track span {
  display: block;
  width: 16.666%;
  height: 100%;
  border-radius: inherit;
  background: var(--primary);
  transition: width 180ms ease;
}

.preview-jump-form { display: flex; align-items: end; gap: 0.45rem; }
.preview-jump-form label { color: var(--muted); font-size: 0.72rem; font-weight: 700; }
.preview-jump-form input {
  width: 6.4rem;
  border: 1px solid var(--line);
  border-radius: 0.75rem;
  padding: 0.7rem;
  color: var(--ink);
  background: var(--surface);
}

.preview-question-card {
  padding: clamp(1.25rem, 4vw, 2.2rem);
  border: 1px solid var(--line);
  border-radius: 1.5rem;
  background: var(--surface);
  box-shadow: 0 1.4rem 3.5rem rgba(28, 52, 68, 0.09);
}

.preview-question-card.is-repair { border-color: #efc7aa; }
.preview-question-meta-top { display: flex; justify-content: space-between; color: var(--muted); font-size: 0.76rem; font-weight: 750; }

.preview-repair-notice {
  margin: 1rem 0 0;
  border-radius: 0.8rem;
  padding: 0.75rem 0.9rem;
  color: #7b3a15;
  background: var(--repair-soft);
  font-size: 0.82rem;
  line-height: 1.6;
}

.preview-prompt {
  margin: clamp(1.5rem, 5vw, 2.6rem) 0 0;
  font-size: clamp(1.55rem, 5vw, 2.35rem);
  line-height: 1.5;
  letter-spacing: 0.01em;
}

.preview-cue {
  display: inline-block;
  margin: 0.75rem 0 0;
  border-radius: 0.55rem;
  padding: 0.35rem 0.55rem;
  color: #536477;
  background: var(--soft);
  font-size: 0.82rem;
}

.preview-answer-form { margin-top: clamp(1.75rem, 5vw, 2.75rem); }
.preview-answer-form label { display: block; margin-bottom: 0.55rem; color: var(--muted); font-size: 0.8rem; font-weight: 750; }
.preview-answer-row { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 0.6rem; }

.preview-answer-row input {
  min-width: 0;
  border: 2px solid #cfdbe2;
  border-radius: 0.9rem;
  padding: 0.9rem 1rem;
  color: var(--ink);
  outline: none;
}

.preview-answer-row input:focus { border-color: var(--primary); box-shadow: 0 0 0 0.22rem rgba(23,107,104,0.12); }
.preview-answer-row button,
.preview-result button {
  border: 0;
  border-radius: 0.9rem;
  padding: 0.9rem 1.25rem;
  color: #fff;
  background: var(--primary);
  font-weight: 800;
  cursor: pointer;
}

.preview-result {
  margin-top: 1.4rem;
  border-top: 1px solid var(--line);
  padding-top: 1.25rem;
}

.preview-result-title { margin: 0; color: var(--primary-dark); font-weight: 850; }
.preview-result.is-wrong .preview-result-title { color: var(--repair); }
.preview-diagnosis {
  margin: 0.7rem 0 0;
  border-radius: 0.7rem;
  padding: 0.65rem 0.8rem;
  color: #5d4938;
  background: #fff6e9;
  font-size: 0.82rem;
  line-height: 1.55;
}
.preview-canonical-label { margin: 1rem 0 0.2rem; color: var(--muted); font-size: 0.72rem; }
.preview-canonical { margin: 0 0 1rem; font-size: 1.3rem; font-weight: 800; line-height: 1.45; }

.preview-audio-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-height: 2.9rem;
  margin: 0 0 1rem;
}

.preview-audio-row button {
  flex: 0 0 auto;
  border: 1px solid #9fc9c5;
  padding: 0.72rem 0.9rem;
  color: var(--primary-dark);
  background: var(--accent);
  font-size: 0.8rem;
}

.preview-audio-row button:disabled { cursor: wait; opacity: 0.65; }
.preview-audio-row span { color: var(--muted); font-size: 0.75rem; line-height: 1.45; }

.preview-curriculum-meta {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.7rem;
  margin: 2rem 0 0;
  border-top: 1px solid var(--line);
  padding-top: 1rem;
}

.preview-curriculum-meta div { min-width: 0; }
.preview-curriculum-meta dt { color: var(--muted); font-size: 0.65rem; }
.preview-curriculum-meta dd { margin: 0.25rem 0 0; overflow-wrap: anywhere; font-size: 0.75rem; font-weight: 700; }
.preview-contract-note { margin: 1rem 0 0; color: var(--muted); font-size: 0.72rem; line-height: 1.65; text-align: center; }

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

@media (max-width: 40rem) {
  .preview-topbar { grid-template-columns: 2.6rem minmax(0, 1fr); }
  .preview-reset { grid-column: 1 / -1; justify-self: end; padding: 0.45rem 0.7rem; font-size: 0.75rem; }
  .preview-progress-panel { grid-template-columns: 1fr; align-items: stretch; }
  .preview-jump-form { justify-content: flex-end; }
  .preview-answer-row { grid-template-columns: 1fr; }
  .preview-answer-row button { width: 100%; }
  .preview-curriculum-meta { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .preview-audio-row { align-items: stretch; flex-direction: column; }
  .preview-audio-row button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}