body {
    font-family: Arial, sans-serif;
    text-align: center;
    background-color: #333;
    color: white;
    margin: 0;
    padding: 20px;
    /* Prevent selection and touch callout */
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    -webkit-touch-callout: none;
}

h1 {
    margin: 20px 0;
    color: #4CAF50;
}

#gameContainer {
    display: inline-block;
    position: relative;
    padding: 20px;
    border-radius: 10px;
    transition: all 0.3s;
    cursor: pointer;
}

#gameContainer.focused {
    background-color: rgba(76, 175, 80, 0.1);
    box-shadow: 0 0 20px rgba(76, 175, 80, 0.3);
}

#board {
    border: 2px solid #4CAF50;
    display: block;
    transition: border-color 0.3s;
}

#gameContainer.focused #board {
    border-color: #66ff66;
    box-shadow: 0 0 10px rgba(76, 175, 80, 0.5);
}

#focusIndicator {
    position: absolute;
    top: -10px;
    right: -10px;
    background-color: #4CAF50;
    color: white;
    padding: 5px 10px;
    border-radius: 5px;
    font-size: 12px;
    display: none;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { opacity: 1; }
    50% { opacity: 0.7; }
    100% { opacity: 1; }
}

.game-info {
    display: flex;
    justify-content: center;
    gap: 50px;
    margin: 20px 0;
    font-size: 20px;
}

.score-box {
    background-color: #444;
    padding: 10px 20px;
    border-radius: 5px;
    min-width: 120px;
}

.score-label {
    font-size: 14px;
    color: #aaa;
}

.score-value {
    font-size: 24px;
    font-weight: bold;
    color: #4CAF50;
}

.controls {
    margin: 20px 0;
}

.difficulty-container {
    margin: 20px 0;
}

.difficulty-btn {
    background-color: #555;
    color: white;
    border: 2px solid #666;
    padding: 10px 20px;
    margin: 0 5px;
    font-size: 16px;
    cursor: pointer;
    border-radius: 5px;
    transition: all 0.3s;
}

.difficulty-btn:hover {
    background-color: #666;
    transform: translateY(-2px);
}

.difficulty-btn:focus {
    outline: none;
}

.difficulty-btn.active {
    background-color: #4CAF50;
    border-color: #4CAF50;
}

.difficulty-btn.easy.active {
    background-color: #4CAF50;
}

.difficulty-btn.medium.active {
    background-color: #FFA500;
}

.difficulty-btn.hard.active {
    background-color: #FF4444;
}

.restart-btn {
    background-color: #4CAF50;
    color: white;
    border: none;
    padding: 10px 30px;
    font-size: 18px;
    cursor: pointer;
    border-radius: 5px;
    margin: 10px;
    transition: all 0.3s;
}

.restart-btn:hover {
    background-color: #45a049;
    transform: translateY(-2px);
}

.restart-btn:focus {
    outline: none;
}

.instructions {
    margin: 20px 0;
    color: #aaa;
    font-size: 14px;
}

.focus-hint {
    color: #4CAF50;
    font-size: 16px;
    margin: 10px 0;
    opacity: 0.8;
}

#gameOverMessage {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.game-over-content {
    background-color: #222;
    padding: 40px;
    border-radius: 10px;
    text-align: center;
    border: 2px solid #4CAF50;
}

.game-over-content h2 {
    color: #FF4444;
    margin-bottom: 20px;
}

.game-over-content p {
    font-size: 20px;
    margin: 10px 0;
}