#include <iomanip>

        page.addRule("width:", "80%");

        page.addRule("width", "80%");

    
    CssRule mainGrid2;
    
    //cout.precision(6);    
    for (int i = 1; i < 7; i++) {
        
        string si    = std::to_string(i);
        string ical  = std::to_string(100.0/i);
            
        mainGrid2.addElement(CLASS, grid+"-1-of-"+si);
        mainGrid2.addRule("flex", "0 1 calc("+ical+"% + 10px*2)");
    }

    mainGrid2.addRule({"flex", "1 0"});
    mainGrid2.addRule({"box-sizing", "border-box"});
    mainGrid2.addRule({"flex-wrap", "wrap"});

      make_shared<CssRule>(mainGrid2)