header {
    width: 100%;
    max-width: 800px;
    margin: auto;
}
header .logo {
    text-align: center;
    display: flex;
    justify-content: center;
    flex-wrap: nowrap;
}
header .logo img {
    width: 50%;
    max-width: 400px;
    margin: auto;
}
.page_content {
    width: 100%;
    max-width: 800px;
    margin: auto;
    text-align: center;
}