body { font-family: Arial, sans-serif; text-align: center; margin: 20px; }
table { width: 60%; margin: 20px auto; border-collapse: collapse; }
th, td { border: 1px solid black; padding: 10px; text-align: center; }
th { background-color: #f2f2f2; }
input, button { margin: 5px; padding: 8px; }
canvas { max-width: 600px; margin: 20px auto; }
.hidden { display: none; }