body {
  font-family: Arial, sans-serif;
  background: #000;
  color: #fff;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
}

.container {
  width: 90%;
  max-width: 800px;
  text-align: center;
}

.paragraph {
  font-size: 1.2rem;
  margin-bottom: 20px;
  line-height: 1.5;
}

.paragraph span.correct {
  color: #4caf50;
}

.paragraph span.incorrect {
  color: #f44336;
}

textarea {
  width: 100%;
  height: 150px;
  font-size: 1.2rem;
  padding: 10px;
  margin-bottom: 20px;
  background: #111;
  color: #fff;
  border: 2px solid #fff;
}

.stats {
  display: flex;
  justify-content: space-around;
  margin-bottom: 20px;
  font-size: 1.2rem;
}

button {
  padding: 10px 20px;
  font-size: 1.1rem;
  cursor: pointer;
}

.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 5rem;
  color: #fff;
  z-index: 10;
}

.hidden {
  display: none;
}