Manually resizing a building block
To manually change the width of a block:
Move your mouse cursor over to the edge of the space between two blocks. so that the double-pointed arrow appears.
Select and drag the edge of your block left or right to change the width as required.
As you drag, a guideline ruler appears along with indicators to show what percentage of the container the left and right-hand sides will take up.
Release the edge and the other blocks within the container automatically adjust to fit in with the block's adjusted size.