body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    background-color: #ffffff;
}

header {
    background-color: #21C84E;
    color: #fff;
    text-align: center;
    padding: 15px 0;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}

header img {
    max-width: 100px;
    height: auto;
    margin-bottom: 10px;
}

header h1 {
    margin: 0;
}

.separator {
    display: none;
}

main {
    max-width: 800px;
    margin: 20px auto;
    padding: 0 20px;
}

section {
    margin-bottom: 30px;
}

h2 {
    color: #333;
}

footer {
    margin-top: 50px;
    color: #555;
    text-align: center;
}

footer p {
    margin-bottom: 10px;
}

@media (min-width: 801px) {
    .header-content {
        flex-direction: row;
        justify-content: center;
        align-items: center;
    }

    header img {
        margin-bottom: 0;
        margin-right: 10px;
    }

    header h1 {
        margin-top: 0;
    }

    .separator {
        display: inline-block;
    }
}