can you make a div col-12 for small screens only bootstrap code example

Example 1: bootstrap grid

  

    

      One of three columns
    
    

      One of three columns
    
    

      One of three columns
    
  

Example 2: row class in bootstrap

/*
In Bootstrap, the "row" class is used mainly to hold columns in it.
Bootstrap divides each row into a grid of 12 virtual columns. 
In the following example, the col-md-6 div will have the width of 6/12 of the "row"s div, meaning 50%. 
The col-md-4 will hold 33.3%, and the col-md-2 will hold the remaining 16.66%.
*/