* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #e0f7fa, #ffffff);
}

.container {
    background: rgba(255, 255, 255, 0.85);
    padding: 25px 30px;
    border-radius: 15px;
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    text-align: center;
    width: 320px;
}

h1 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: #00796b;
    text-shadow: 0 0 5px #00bfa5;
}

.board {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 20px;
}

.cell {
    width: 80px;
    height: 80px;
    display: flex;
    justify-content: center;
    align-items: center;
    background: #ffffff80;
    border-radius: 10px;
    font-size: 2rem;
    font-weight: bold;
    color: #00796b;
    cursor: pointer;
    transition: 0.2s;
    box-shadow: 0 0 6px rgba(0, 150, 136, 0.5);
}

.cell:hover {
    transform: scale(1.05);
    box-shadow: 0 0 12px #00bfa5, 0 0 18px #00e5ff;
}

.winning-cell {
    background: #00bfa5;
    color: #fff;
    box-shadow: 0 0 15px #00e5ff, 0 0 25px #00bfa5;
}

#status {
    margin-bottom: 15px;
    font-size: 1.1rem;
    min-height: 22px;
    color: #004d40;
}

button {
    padding: 8px 20px;
    border: none;
    border-radius: 8px;
    background-color: #00796b;
    color: #fff;
    cursor: pointer;
    font-size: 1rem;
    margin: 4px;
    transition: 0.2s;
    box-shadow: 0 0 8px #00bfa5;
}

button:hover {
    background-color: #00bfa5;
    box-shadow: 0 0 12px #00e5ff;
    transform: scale(1.05);
}

@media (max-width: 400px) {
    .cell {
        width: 60px;
        height: 60px;
        font-size: 1.5rem;
    }

    .container {
        width: 90%;
        padding: 20px;
    }

    h1 {
        font-size: 1.5rem;
    }
}