Problem
Write the CSS rule for a main element with the class attribute value of "three-col" that displays its content in three columns using CSS Grid. The first column should be limited to 250px. The second column takes up 2 times the remaining width available space and the last column takes up 1 times that available space (or, in other words, half of the second column).
The gap between the columns is 40 pixels and the child items are vertically aligned.