var pageSettings = {
  red: 200,
  green: 200,
  blue: 200,
background: [
'https://pictures.s3.yandex.net/background.jpg', 'https://pictures.s3.yandex.net/cover-color.jpg', 'https://pictures.s3.yandex.net/cover-grid.jpg', 'https://pictures.s3.yandex.net/cover-typo.jpg', 'https://pictures.s3.yandex.net/cover-wall.jpg'
]
};
var bgColor = 'rgb(' + pageSettings.red + ', ' + pageSettings.green + ', ' + pageSettings.blue + ')';
document.body.style.backgroundColor = bgColor;
var header = document.getElementById('main-header');
console.log(header);
header.style.backgroundImage = 'url(' + getRandom(pageSettings.background); + ')';
var i = 0;
var i = 0;
console.log(pageSettings.background[i]);
console.log(pageSettings.background[++i]);
console.log(pageSettings.background[++i]);
function getRandom(anyArray) {
 var randomNumber = Math.floor(Math.random() * anyArray.length);
  var randomElement = anyArray[randomNumber];
return randomElement;
}
document.getElementsByClassName('card');