body {
  font-family: 'Arial', sans-serif;
  background-color: #f0f8ff;
  text-align: center;
  padding: 20px;
}

.container {
  background: white;
  border-radius: 20px;
  padding: 30px;
  max-width: 800px;
  margin: auto;
  box-shadow: 0 0 10px rgba(0,0,0,0.2);
}

h1 {
  margin-bottom: 20px;
  color: #333;
  font-size: 48px;
}

.example {
  margin: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 120px;
  flex-wrap: wrap;
}

.digit-img {
  width: 64px;
  height: 96px;
  margin: 6px;
  object-fit: contain;
}

.digit-fallback {
  font-size: 72px;
  margin: 6px;
}

.controls {
  margin: 10px 0 0;
}

input {
  font-size: 48px;
  padding: 20px;
  width: 300px;
  text-align: center;
  border: 3px solid #888;
  border-radius: 10px;
  box-shadow: 0 0 8px rgba(0,0,0,0.2);
}

button {
  padding: 20px 40px;
  margin-left: 20px;
  font-size: 28px;
  cursor: pointer;
  border-radius: 10px;
  border: none;
  background: #4CAF50;
  color: white;
}

#feedback {
  margin-top: 15px;
  font-size: 28px;
}

#timer {
  margin-top: 30px;
  font-weight: bold;
  color: #e60000;
  font-size: 28px;
}

#result {
  margin-top: 30px;
  font-size: 30px;
}

.hidden {
  display: none;
}