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

body {
    font-family: 'Arial', sans-serif;
    background-color: #f0f8ff; 
    color: #333;
    text-align: center;
    padding: 20px;
}
#background-video {
    position: fixed; 
    top: 0;
    left: 0;
    width: 100%; 
    height: 100%; 
    object-fit: cover; 
    z-index: -1; 
}

.game-container {
    max-width: 600px;
    margin: 0 auto;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 10px;
    margin: 20px 0;
    padding: 0;
}

.card {
    background-color: #fff;
    border: 2px solid #00796b; 
    border-radius: 8px;
    height: 100px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    color: #007d6f; 
    cursor: pointer;
    transition: transform 0.2s ease-in-out;
}

.card.flipped {
    background-color: #fff;
    color: #00796b; 
}

.card:not(.flipped) {
    background-color: #004d40; 
    color: transparent;
}

.card:hover {
    transform: scale(1.05); 
}

#status {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: #000000;
}

button {
    background-color: #00796b;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 10px 20px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: #004d40;
}

.hidden {
    display: none;
}

#game-over {
    margin-top: 20px;
}

#game-over .message {
    font-size: 1.5rem;
    color: #000000;
}

#winner {
    font-size: 2rem;
    font-weight: bold;
    color: #d32f2f;
}

@media screen and (max-width: 600px) {
    .card {
        height: 80px; 
        font-size: 1.5rem; 
    }

    button {
        font-size: 1rem;
        padding: 8px 16px;
    }
}
/* Responsive Design */

/* Mobile devices (portrait mode) */
@media (max-width: 768px) {
    #backgroundVideo {
        width: 100vw;
        height: 100vh;
        object-fit: cover;
    }

    .btn {
        font-size: 18px;
        padding: 12px 24px;
    }
}

/* Extra small devices (phones in landscape) */
@media (max-width: 480px) {
    .btn {
        font-size: 16px;
        padding: 10px 20px;
    }
}

/* Tablets */
@media (min-width: 769px) and (max-width: 1024px) {
    .btn {
        font-size: 20px;
        padding: 15px 30px;
    }
}

/* Larger screens (Desktops) */
@media (min-width: 1025px) {
    .btn {
        font-size: 24px;
        padding: 20px 40px;
    }
}