function setColorBlock(num) {
    document.getElementById('block_' + num + '_header').className = 'colorBlockHeader';
    document.getElementById('block_' + num + '_img').src = '/theme_357/images/agencies_pics/color/' + num + '.jpg';
    document.getElementById('block_' + num + '_description').className = 'colorBlockDescription';
}

function setGrayBlock(num) {
    document.getElementById('block_' + num + '_header').className = 'grayBlockHeader';
    document.getElementById('block_' + num + '_img').src = '/theme_357/images/agencies_pics/gray/' + num + '.jpg';
    document.getElementById('block_' + num + '_description').className = 'grayBlockDescription';
}