if(document.addEventListener) { window.addEventListener("load", showModal, false); }
else if (window.attachEvent)  { window.attachEvent("onload", showModal); }
else { window.onload = showModal; }

function showModal() {
	
	var modal_mask = document.getElementById("modal_mask");
	var modal_box  = document.getElementById("modal_box");
	var modal_link = document.getElementById("modal_link");
	
	var scrollXY   = getScrollXY();
	var viewport   = getSize();

	//modal_link.href = alink.href;

	modal_box.style.display = 'block';
	modal_box.style.top = scrollXY[1] + viewport[1] / 2 - 230 + "px";
	modal_mask.style.display = 'block';
	modal_mask.style.height = getDocHeight() + "px";

	return false;
	
}

function closeModal(ret) {
	
	var modal_mask = document.getElementById("modal_mask");
	var modal_box  = document.getElementById("modal_box");
	var modal_link = document.getElementById("modal_link");
	
	if(!ret) { modal_link.href = "#"; }
	modal_mask.style.display = "none";
	modal_box.style.display = "none";

	return ret;
	
}

function getDocHeight() {
	var D = document;
	return Math.max(
		Math.max(D.body.scrollHeight, D.documentElement.scrollHeight),
		Math.max(D.body.offsetHeight, D.documentElement.offsetHeight),
		Math.max(D.body.clientHeight, D.documentElement.clientHeight)
	);
}

function getScrollXY() {
	var scrOfX = 0, scrOfY = 0;
	if( typeof( window.pageYOffset ) == 'number' ) {
		//Netscape compliant
		scrOfY = window.pageYOffset;
		scrOfX = window.pageXOffset;
	} else if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) {
		//DOM compliant
		scrOfY = document.body.scrollTop;
		scrOfX = document.body.scrollLeft;
	} else if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) {
		//IE6 standards compliant mode
		scrOfY = document.documentElement.scrollTop;
		scrOfX = document.documentElement.scrollLeft;
	}
	return [ scrOfX, scrOfY ];
}

function getSize() {
	var myWidth = 0, myHeight = 0;
	if( typeof( window.innerWidth ) == 'number' ) {
		//Non-IE
		myWidth = window.innerWidth;
		myHeight = window.innerHeight;
	} else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
		//IE 6+ in 'standards compliant mode'
		myWidth = document.documentElement.clientWidth;
		myHeight = document.documentElement.clientHeight;
	} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
		//IE 4 compatible
		myWidth = document.body.clientWidth;
		myHeight = document.body.clientHeight;
	}
	return [ myWidth, myHeight ];
}