header {
    padding: 1.5% 20%;
}

.title {
    font-size: xx-large;
}

main {
    width: 60%;
}

footer {
    width: 60%;
}

.left-container {
    flex: 1;
}

.center-container {
    flex: 1;
}

.right-container {
    flex: 5;
}