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

body {
    margin: 0;
    background-color: #234;
    font-family: sans-serif;
    font-family: arial, sans-serif;
}

nav {
    background-color: #666;
    padding: 10px;
}

.nav {
    list-style: none;
    padding: 0; margin: 0;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
}

.nav li a {
    background-color: yellow;
    color: #333;
    padding: 10px 15px;
    text-decoration: none;
    display: inline-block;
    font-weight: bold;
}

.flex-container {
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-items: flex-start;
    gap: 20px;
    padding: 40px;
}

.main {
    min-width: 300px; min-height: 300px;
    background-color: pink;
}

.boxes {
    display: flex;
    flex-direction: wrap;
    gap: 20px;
    flex-wrap: wrap;
}

.boxes div {
    width: 140px; height: 140px;
    background-color: yellow;
}

/* Responsive styles */
@media (max-width: 768px) {

    .flex-container {
        flex-direction: column;
        align-items: center;
    }

    .boxes {
        flex-direction: row;
    }

    .boxes div {
        width: 100px;
        height: 100px;
    }

    .main {
        width: 250px;
        height: 250px;
    }
}

@media (max-width: 480px) {

    .nav {
        flex-direction: column;
        align-items: center;
    }

    .main {
        width: 200px;
        height: 200px;
    }

    .boxes div {
        width: 90px;
        height: 90px;
    }
}