.flex-container
    width 720px
    margin 0 auto

html
    font-size 18px

@media (max-width: 1600px)
    html
        font-size 18px
    .flex-container
        width 720px

@media (max-width: 1200px)
    html
        font-size 18px
    .flex-container
        width 640px

@media (max-width: 688px)
    html
        font-size 16px
    
    .flex-container
        display block
        width calc(100% - 32px)
        padding-left 16px
        padding-right 16px