Horizontal align center on top bar

Try setting the alignment to center in "Customize > Layout > Top Bar".

You also have some CSS in Simple CSS telling one of the widgets to float right.

Try setting the alignment to center in “Customize > Layout > Top Bar”.

that is not I want.

all of the three items is not stick to the top of the top bar.
I would like these three align center, alone the red line in the about image:

Try setting the alignment to center in “Customize > Layout > Top Bar”.

That is not what I want.

All of the three items is now sticking to the top of the top bar.
I would like these three items align to center horizontally, alone the red line in the about image:

Ahh got it.

Try this instead:

.inside-top-bar {
    display: flex;
    align-items: center;
    justify-content: center;
}

.inside-top-bar h3,
.inside-top-bar h5 {
    margin-bottom: 0;
}

If you need old browser support, run that code through this tool: https://autoprefixer.github.io/