/* General Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Orbitron', sans-serif;
    background: linear-gradient(135deg, #1e3c72, #2a5298);
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    overflow: hidden;
}

.container {
    text-align: center;
    background: rgba(255, 255, 255, 0.1);
    padding: 30px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    max-width: 90%;
    width: 100%;
}

h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    text-shadow: 2px 2px 5px rgba(0, 0, 0, 0.3);
}

.mode-selection, .difficulty-selection, .player-selection {
    margin-bottom: 20px;
}

button {
    background: #ff6f61;
    color: #fff;
    border: none;
    padding: 10px 20px;
    margin: 5px;
    border-radius: 10px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
}

button:hover {
    background: #ff3b2f;
    transform: translateY(-2px);
    box-shadow: 0 6px 8px rgba(0, 0, 0, 0.3);
}

#game-board {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin: 20px auto;
    width: 100%;
    max-width: 300px;
}

.cell {
    width: 100%;
    aspect-ratio: 1;
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    border-radius: 10px;
}

.cell:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

#status {
    margin-top: 20px;
    font-size: 1.2rem;
    font-weight: bold;
}

#reset-button {
    margin-top: 20px;
    padding: 10px 20px;
    font-size: 1rem;
    cursor: pointer;
    background: #4caf50;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
}

#reset-button:hover {
    background: #45a049;
    transform: translateY(-2px);
    box-shadow: 0 6px 8px rgba(0, 0, 0, 0.3);
}

.hidden {
    display: none;
}

/* Animations */
@keyframes pop {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

.winning-cell {
    animation: pop 0.5s ease;
    background: rgba(76, 175, 80, 0.3);
}

/* Responsive Design */
@media (max-width: 768px) {
    h1 {
        font-size: 2.5rem;
    }

    .cell {
        font-size: 2rem;
    }

    #status {
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 2rem;
    }

    .cell {
        font-size: 1.5rem;
    }

    #status {
        font-size: 0.9rem;
    }
}