Changing order of the content.

Hello fellow wordpress users, i have a question!
I made a simple theme with a header, menu, widgets left and content right.
This all is displayed good on desktop but when i resize the browser window or vieuw it on mobile the overal layout changes according to the screen size. when this happens the widgets are displayed first and the content second.

I want to change this, content first and then the widgets. i edited the index.php with the line
<?php get_sidebar('top'); ?>
i moved it from the top to the part after it gets the content of the page but this doesnt change it. how do i change this?