body {
    font-family: Arial, sans-serif;
    margin: 20px;
    padding: 0;
    background-color: #fff;
    color: #000;
}

header {
    text-align: center;
    padding: 30px;
    background-color: #f8f8f8;
    border-bottom: 1px solid #ddd;
}

h1 {
    font-size: 2em;
    margin: 15px 0;
}

nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.nav-button {
    text-decoration: none;
    font-size: 1.2em;
    color: #003366;
    border: 2px solid #003366;
    padding: 8px 15px;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
    white-space: nowrap;
    display: inline-block;
    text-align: center;
    min-width: 100px
}

.nav-button:hover {
    background-color: #003366;
    color: #fff;
}

main {
    margin-top: 30px;
}

section {
    margin-bottom: 30px;
}

.profile-img {
    display: block;
    width: 100%;
    max-width: 250px;
    height: auto;
    margin: 30px auto;
    border-radius: 10px;
}

@media (max-width: 768px) {
    body {
        margin: 10px;
    }

    h1 {
        font-size: 1.8em;
    }

    .nav-button {
        font-size: 1em;
        padding: 6px 12px;
    }

    main {
        margin-top: 20px;
    }

    .profile-img {
        max-width: 100%;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.5em;
    }

    nav ul {
        flex-direction: column;
        gap: 10px;
    }

    .nav-button {
        font-size: 1em;
        padding: 10px;
        width: 100%;
    }
}