body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    background-color: #f0f2f5;
    color: #333;
    padding-top: 20px;
}
h1 {
    color: #1a2b4d;
}
.controls {
    margin: 20px 0;
    display: flex;
    gap: 10px;
}
.controls button {
    font-size: 1rem;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    background-color: #007bff;
    color: white;
}
#solve-btn { background-color: #ffc107; color: #333; }
#auto-btn { background-color: #28a745; }

#game-canvas {
    background-color: #222;
    border: 3px solid #333;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

#status-message {
    margin-top: 20px;
    font-size: 1.2rem;
    font-weight: bold;
}
.back-link {
    display: inline-block;
    margin-bottom: 20px;
    font-size: 1rem;
    color: #007bff;
    text-decoration: none;
}
.back-link:hover { text-decoration: underline; }