// JavaScript Document

function imgSize() {

	var imgRate = ((document.documentElement.clientWidth * 0.8) * 0.8) / 1997;

	var imgWidth = Math.round(1997 * imgRate);

	var imgHeight = Math.round(716 * imgRate);

	var imgMain = document.getElementById('img-main');

	imgMain.style.height = imgHeight + 'px';

	imgMain.style.width = imgWidth + 'px';

}



window.onresize = function() {

	imgSize();

};



function rollImg (imgFlag) {

	switch (imgFlag) {

		case 0:

			document.getElementById('img-main').src = 'ad.png';

		break

		case 1:

			document.getElementById('img-main').src = 'ad2.png';

		break

	}

}