body {
  font-family: Arial, sans-serif;
  background: #f4f4f4;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
}

.container {
  background: #fff;
  padding: 20px 30px;
  border-radius: 8px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
  max-width: 600px;
  width: 100%;
  text-align: center;
}

#progress-container {
  width: 100%;
  background-color: #ddd;
  border-radius: 8px;
  margin-bottom: 20px;
  height: 20px;
}

#progress-bar {
  height: 100%;
  width: 0%;
  background-color: #3498db;
  border-radius: 8px;
  transition: width 0.3s ease;
}

#answers-container {
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

button {
  padding: 10px 15px;
  border: none;
  border-radius: 4px;
  background: #3498db;
  color: #fff;
  cursor: pointer;
  transition: transform 0.2s;
}

button:hover {
  background: #2980b9;
}

.correct {
  background: #2ecc71 !important;
  animation: flash 0.5s;
}

.wrong {
  background: #e74c3c !important;
  animation: shake 0.5s;
}

@keyframes flash {
  0% { transform: scale(1); }
  50% { transform: scale(1.05); }
  100% { transform: scale(1); }
}

@keyframes shake {
  0% { transform: translateX(0); }
  25% { transform: translateX(-5px); }
  50% { transform: translateX(5px); }
  75% { transform: translateX(-5px); }
  100% { transform: translateX(0); }
}