:root {
  --bg: #f7f4ea;
  --panel: #fffdf7;
  --ink: #1f2a1f;
  --accent: #205f4c;
  --accent-soft: #d8ece5;
  --danger: #a23b2a;
  --danger-soft: #f6dfda;
  --border: #d8d0bf;
}

body {
  background:
    radial-gradient(circle at top left, rgba(32, 95, 76, 0.12), transparent 28%),
    radial-gradient(circle at top right, rgba(162, 59, 42, 0.08), transparent 24%),
    var(--bg);
  color: var(--ink);
}

.lab-panel {
  max-width: 920px;
  margin: 0 auto;
  padding: 28px 32px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: 0 14px 40px rgba(38, 45, 34, 0.08);
}

.lab-panel h1,
.lab-panel h2,
.lab-panel h3 {
  margin-top: 0;
}

.lab-row {
  display: flex;
  gap: 20px;
  justify-content: center;
  align-items: stretch;
  flex-wrap: wrap;
  margin-top: 24px;
}

.lab-bin {
  flex: 1 1 320px;
  padding: 18px;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: #fff;
}

.lab-bin.positive {
  background: var(--accent-soft);
}

.lab-bin.negative {
  background: var(--danger-soft);
}

.lab-image-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(110px, 1fr));
  gap: 14px;
  margin-top: 16px;
}

.lab-image-grid img,
.probe-image,
.training-image,
.mentor-image,
.hero-image {
  width: 100%;
  object-fit: contain;
}

.hero-image {
  max-width: 360px;
  display: block;
  margin: 20px auto;
}

.training-layout {
  display: grid;
  grid-template-columns: 120px minmax(240px, 1fr) 120px;
  gap: 18px;
  align-items: center;
  min-height: 340px;
}

.response-side {
  font-size: 1.25rem;
  font-weight: 700;
}

.response-side.left {
  text-align: left;
}

.response-side.right {
  text-align: right;
}

.training-card,
.probe-card,
.mentor-card {
  text-align: center;
}

.training-image {
  max-width: 260px;
  margin-top: 12px;
}

.probe-image {
  max-width: 240px;
  margin: 18px auto 6px;
  display: block;
}

.mentor-image {
  max-width: 220px;
  display: block;
  margin: 18px auto;
}

.feedback-mark {
  font-size: 132px;
  line-height: 1;
}

.feedback-mark.correct {
  color: var(--accent);
}

.feedback-mark.incorrect {
  color: var(--danger);
}

.tag-positive {
  color: var(--accent);
  font-weight: 700;
}

.tag-negative {
  color: var(--danger);
  font-weight: 700;
}

@media (max-width: 700px) {
  .lab-panel {
    padding: 22px 18px;
  }

  .training-layout {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .response-side.left,
  .response-side.right {
    text-align: center;
  }
}