A CSS Grid behavior that I don't understand

Take a look at the picture. I have set my grid to have only one column as indicated by the arrow mark, but it has two columns as indicated by the property being set in the blue box.

Here’s the link to my project: https://codepen.io/skanda1395/pen/RXNZZO

What’s going on here?

a link to your code would help a lot

I’ve provided the link to my code above.

hmmm i get a solid blue background without the white lines, looks good

I was asking about the grid. Could you provide a screenshot?

try using a different browser, im using chrome and there is no grid visable