body {
    font-family: Arial, sans-serif;
    text-align: center;
    background-size: cover; 
    background-position: center;
    background-attachment: fixed;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    margin: 0;
}

@media (max-width: 768px) { /* Phones */
    body {
        background-image: url("resources/bg_mob.png");
    }
}

@media (min-width: 769px) { /* Laptops & PCs */
    body {
        background-image: url("resources/bg_pc.png");
    }
}

h1 {
    margin-bottom: 20px;
    color: white;
    text-shadow: 2px 2px 5px rgba(0, 0, 0, 0.7);
    font-size: 2.5rem;
    letter-spacing: 2px;
    text-transform: uppercase;
}

.game-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
}

.scoreboard {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 500px;
    margin-bottom: 20px;
}

.player, .ai {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

#player-score, #ai-score{
    font-size: 40px;
    font-weight: bold;
    color: white;
}

.player, #player-score {
    position: static;
    margin-left: -200px;
}

.ai, #ai-score {
    position: static;
    margin-right: -200px;
}

.player img{
    width: 200px;
    height: 200px;
    margin-left: -200px;
}

.ai img {
    width: 200px;
    height: 200px;
    margin-right: -200px;
}

.board {
    display: grid;
    grid-template-columns: repeat(3, 120px);
    grid-template-rows: repeat(3, 120px);
    gap: 5px;
    background: rgba(255, 255, 255, 0.1);
    padding: 10px;
    border-radius: 15px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.5);
}

.cell {
    width: 120px;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    cursor: pointer;
    background: rgba(0, 0, 0, 0.3);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.5);
    transition: background 0.3s ease-in-out;
}

.cell:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.1);
}

button {
    padding: 10px 20px;
    font-size: 1.2rem;
    margin-top: 20px;
    border: none;
    color: white;
    cursor: pointer;
    background: linear-gradient(135deg, #46b430, #1ea274);
    border-radius: 10px;
    transition: all 0.3s ease-in-out;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.3);
}

button:hover {
    background: linear-gradient(135deg, #d1d142, #66c41e);
    transform: scale(1.05);
}

.difficulty-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 15px;
    color: white;
    font-size: 1.2rem;
}

.difficulty-btn {
    background: transparent;
    border: 2px solid #00ffcc;
    color: #00ffcc;
    padding: 5px 15px;
    font-size: 1rem;
    cursor: pointer;
    transition: 0.3s;
    border-radius: 5px;
}

.difficulty-btn:hover {
    background: #00ffcc;
    color: black;
}

.difficulty-btn.active {
    background: #00ffcc;
    color: black;
    font-weight: bold;
}

.choice-container-btn {
    background: transparent;
    border: 2px solid cyan;
    color: cyan;
    font-weight: bold;
    padding: 10px 20px;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease-in-out;
}

.choice-container-btn:hover {
    background: rgba(0, 255, 255, 0.2);
    box-shadow: 0 0 10px cyan;
    transform: scale(1.1);
}

.popup {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7); /* Semi-transparent black */
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.popup-content {
    background: white;
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    animation: fadeIn 0.3s ease-in-out;
}

#popupMessage {
    font-size: 20px;
    font-weight: bold;
    margin-bottom: 15px;
}

.popup-content button {
    background: #3498db;
    color: white;
    border: none;
    padding: 10px 20px;
    font-size: 16px;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s;
}

.popup-content button:hover {
    background: #2980b9;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.selected {
    background-color: #FFD700;
    color: black;
    border: 2px solid #FFF;
    font-weight: bold;
}