CSS grid. grid-column not applying

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Hi guys, here I am trying to move the navbar to the left of the page. aka let it occupy the first column of the two. But it has not moved. Can someone help me, thanks

In your css, you’ve applied all the grid (and one ‘gird’) properties to body, but nav-bar is actually a child of main-doc, not body.

If you change the css selector to #main-doc rather than body, then it works as expected.