$(document).ready(function(){
  random_box_color();
  
  $("#random").on('click', function(){
    random_box_color();
  });
  
  $("#shadow").on('click', function(){
    $('section.main').toggleClass('shadow');
  });
});


function random_box_color() {
  $('.box').each(function(e){
    var r = randomColor();
    var color = "rgb(" + r[0] + ", " + r[1] + ", " + r[2] + ")";
    
    $(this).css({"background-color": color});
  });
}

function randomColor() {
  var rgb_val = [];
  
  for (i = 0; i < 3; i++) {
    rgb_val.push(randInt(0, 255));
  }
  
  return rgb_val;
}

// For random integer
function randInt(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}