CSS Grid: Task Board

Hey everyone,

I´ve completed the task to create the CSS Grid Task Board but I just can´t get the card collumns section to align in the center.

Here´s the CSS I used:

.container {
display: grid;
width: 1000px;
grid-template: 1fr 1fr 1fr / 1fr 1fr 1fr;
gap: 20px;
justify-content: center;
}

Does anyone have any idea where I´m stuck?

CSS Grid: Task Board