body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #333;
    color: #f0f0f0;
    transition: background-color 0.3s, color 0.3s;
}

body:not(.dark-mode) {
    background-color: #f0f0f0;
    color: #333;
}

#game-container {
    text-align: center;
}

#grid-container {
    display: inline-grid;
    grid-template-columns: repeat(5, 60px);
    grid-gap: 5px;
    background-color: #6a5b4f;
    border-radius: 5px;
    padding: 5px;
    margin-bottom: 20px;
}

body:not(.dark-mode) #grid-container {
    background-color: #bbada0;
}

.cell {
    width: 60px;
    height: 60px;
    background-color: #4a4a4a;
    border-radius: 3px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    transition: all 0.3s ease;
    user-select: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    cursor: pointer;
}

body:not(.dark-mode) .cell {
    background-color: #cdc1b4;
}

#score-container {
    margin-bottom: 20px;
    font-size: 18px;
}

#new-game-btn {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    background-color: #8f7a66;
    color: white;
    border: none;
    border-radius: 3px;
    cursor: pointer;
}

body:not(.dark-mode) #new-game-btn {
    background-color: #6a5b4f;
}

#dark-mode-toggle {
    font-size: 24px;
    cursor: pointer;
    margin-bottom: 10px;
}

.pop-animation {
    animation: pop 0.3s ease-in-out;
}

@keyframes pop {
    0% { transform: scale(1); }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); }
}