body {
  margin: 0;
  padding: 0;
  background-color: #e6f4e6;
  font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
  color: #2e4d2e;
  min-height: 100vh;
}

.container {
  max-width: 800px;
  margin: 60px auto;
  padding: 30px;
  border-radius: 16px;
  background: #f8fff8;
  box-shadow: 0 0 16px rgba(0, 128, 0, 0.1);
  border: 1px solid #cce6cc;
}

.title {
  text-align: center;
  font-size: 28px;
  margin-bottom: 20px;
  letter-spacing: 1px;
  color: #2e7d32;
}

.mode-switch {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 30px;
}

.mode-switch button {
  background: #f0fff0;
  border: 2px solid #66bb6a;
  color: #2e7d32;
  padding: 10px 16px;
  font-weight: bold;
  border-radius: 8px;
  transition: 0.3s ease;
}

.mode-switch button:hover {
  background: #c8e6c9;
  color: #1b5e20;
}

#question-type {
  font-size: 16px;
  color: #388e3c;
  margin-bottom: 6px;
}

#question {
  font-size: 20px;
  margin-bottom: 12px;
  line-height: 1.5;
}

.stats-bar {
  font-size: 15px;
  margin-bottom: 12px;
  padding: 8px 12px;
  background: #edf8ed;
  border: 1px solid #b2d8b2;
  border-radius: 6px;
  color: #2e7d32;
}

#options {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 20px;
}

.option-label {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  border-radius: 8px;
  background: #f1faf1;
  border: 1px solid #cde7cd;
  transition: all 0.3s ease;
  cursor: pointer;
}

.option-label:hover {
  background: #d7f0d7;
}

.option-label input[type='radio'],
.option-label input[type='checkbox'] {
  margin-right: 12px;
  transform: scale(1.2);
  accent-color: #4caf50;
}

.option-text {
  font-size: 16px;
  color: #2e4d2e;
}

.feedback {
  font-size: 16px;
  margin-bottom: 18px;
  min-height: 24px;
}

.button-group {
  display: flex;
  justify-content: space-between;
  gap: 10px;
}

.button-group button {
  flex: 1;
  padding: 12px;
  background: #a5d6a7;
  color: #1b5e20;
  font-weight: bold;
  border: none;
  border-radius: 8px;
  transition: all 0.3s ease;
}

.button-group button:hover {
  background: #81c784;
}