:root {
  --ink: #18202f;
  --muted: #667085;
  --paper: #fbfaf6;
  --panel: #ffffff;
  --line: #d9dee8;
  --brand: #1b766f;
  --brand-dark: #12524d;
  --accent: #e6a23c;
  --correct: #1f8f5f;
  --wrong: #c24132;
  --shadow: 0 18px 45px rgba(24, 32, 47, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    linear-gradient(rgba(251, 250, 246, 0.88), rgba(251, 250, 246, 0.96)),
    url("https://images.unsplash.com/photo-1503676260728-1c00da094a0b?auto=format&fit=crop&w=1600&q=80");
  background-size: cover;
  background-position: center;
  font-family: Arial, Helvetica, sans-serif;
}

button {
  font: inherit;
}

.app-shell {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 32px 0;
}

.hero {
  min-height: 220px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--brand-dark);
  font-weight: 700;
  text-transform: uppercase;
  font-size: 0.82rem;
}

h1 {
  margin: 0;
  font-size: clamp(2.4rem, 7vw, 5.2rem);
  line-height: 0.95;
  letter-spacing: 0;
}

.intro {
  max-width: 520px;
  margin: 18px 0 0;
  color: #3b4558;
  font-size: 1.12rem;
  line-height: 1.55;
}

.score-card {
  min-width: 140px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: var(--shadow);
  text-align: center;
}

.score-label {
  display: block;
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
}

#score {
  display: block;
  margin-top: 6px;
  color: var(--brand-dark);
  font-size: 2.4rem;
}

.game-panel,
.teacher-notes {
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.game-panel {
  padding: 26px;
}

.top-bar,
.actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.level-pill {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  color: #fff;
  background: var(--brand);
  font-weight: 700;
  font-size: 0.9rem;
}

.progress-text {
  margin: 8px 0 0;
  color: var(--muted);
}

.icon-button {
  min-width: 72px;
  height: 44px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--brand-dark);
  background: #fff;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 700;
}

.question-area {
  min-height: 168px;
  margin-top: 24px;
  padding: 24px;
  border-left: 5px solid var(--accent);
  background: #fff8ec;
  border-radius: 8px;
}

.scenario {
  margin: 0 0 12px;
  color: var(--muted);
  font-weight: 700;
}

.question-area h2 {
  margin: 0;
  font-size: clamp(1.35rem, 3vw, 2.1rem);
  line-height: 1.25;
}

.options-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 22px;
}

.option-button {
  min-height: 70px;
  padding: 14px 16px;
  border: 2px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: #fff;
  cursor: pointer;
  text-align: left;
  line-height: 1.35;
}

.option-button:hover,
.option-button:focus {
  border-color: var(--brand);
  outline: none;
}

.option-button.correct {
  border-color: var(--correct);
  background: #eaf8f0;
}

.option-button.wrong {
  border-color: var(--wrong);
  background: #fff0ee;
}

.option-button:disabled {
  cursor: default;
}

.feedback {
  margin-top: 18px;
  padding: 16px;
  border-radius: 8px;
  line-height: 1.5;
}

.feedback.correct {
  color: #155a3e;
  background: #eaf8f0;
}

.feedback.wrong {
  color: #8d2b22;
  background: #fff0ee;
}

.hidden {
  display: none;
}

.actions {
  margin-top: 22px;
  justify-content: flex-end;
}

.primary-button {
  min-width: 120px;
  min-height: 46px;
  padding: 0 20px;
  border: 0;
  border-radius: 8px;
  color: #fff;
  background: var(--brand);
  cursor: pointer;
  font-weight: 700;
}

.primary-button:disabled {
  background: #aab4c1;
  cursor: default;
}

.teacher-notes {
  margin-top: 24px;
  padding: 24px;
}

.teacher-notes h2 {
  margin: 0 0 16px;
  font-size: 1.2rem;
}

.notes-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.notes-grid article {
  min-height: 120px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.notes-grid h3 {
  margin: 0 0 8px;
  color: var(--brand-dark);
}

.notes-grid p {
  margin: 0;
  color: var(--muted);
  line-height: 1.45;
}

@media (max-width: 760px) {
  .app-shell {
    width: min(100% - 20px, 1120px);
    padding: 18px 0;
  }

  .hero {
    min-height: 210px;
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
  }

  .score-card {
    width: 100%;
  }

  .game-panel,
  .teacher-notes {
    padding: 18px;
  }

  .options-grid,
  .notes-grid {
    grid-template-columns: 1fr;
  }

  .question-area {
    min-height: 190px;
    padding: 18px;
  }
}