body {
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #444444;
    color: #f9f9f9;
}

header {
    background-color: #2C2C2C;
    color: white;
    padding: 15px 0;
    text-align: center;
}

nav {
    display: flex;
    justify-content: center;
    margin-top: 10px;
}

nav a {
    color: #D3D3D3;
    margin: 0 20px;
    text-decoration: none;
    font-size: 18px;
    padding: 10px 20px;
    background-color: #444444;
    border-radius: 8px;
    transition: background-color 0.3s ease;
}

nav a:hover {
    background-color: #555555;
}

.biography-container {
    max-width: 900px;
    margin: 30px auto;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    padding: 20px;
    background-color: #636363;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    border-radius: 8px;
}

.biography {
    flex: 1;
    padding-right: 20px;
}

.biography h2 {
    font-size: 24px;
    color: #f9f9f9;
}

.biography p {
    font-size: 16px;
    color: #D3D3D3;
    line-height: 1.6;
}

.biography img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
}

@media only screen and (max-width: 768px) {
    header {
        padding: 15px 0;
        text-align: center;
    }

    nav {
        display: flex;
        justify-content: center;
        margin-top: 10px;
    }

    nav a {
        margin: 0 20px;
        font-size: 16px;
    }

    .biography-container {
        flex-direction: column;
        align-items: center;
        padding: 20px;
    }

    .biography img {
        width: 120px;
        height: 120px;
    }

    .biography {
        text-align: center;
        padding-right: 0;
    }

    .biography h2 {
        font-size: 20px;
    }

    .biography p {
        font-size: 14px;
        line-height: 1.4;
    }
}

@media only screen and (max-width: 480px) {
    nav a {
        font-size: 14px;
        padding: 10px;
    }

    .biography h2 {
        font-size: 18px;
    }

    .biography p {
        font-size: 15px;
    }
}