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The predefined classes xs-lower-one-col, xs-lower-two-col, xs-lower-three-col when applied to block level containers will change the grid-column-template to the given number.
For example xs-lower-onetwo-col class applied on a 4 column block, will change that block to 2 columns layout starting at xs size, so both xs and xxs sizes will change the block to a 2 column layout.
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