/* 画像切り替え */
function c_img(method, index) {


	var btn	 = document.getElementById(index);

	if(method == 'over'){

		if (IE='\v'=='v' == true) { btn.style.filter = 'alpha(opacity=50)'; }
		if (navigator.userAgent.toLowerCase().indexOf("firefox") != -1) { btn.style.MozOpacity = 0.5; }
		if (Safari=/a/.__proto__=='//' == true) { btn.style.opacity = 0.5; }
	
	} else {

		if (IE='\v'=='v' == true) { btn.style.filter = 'alpha(opacity=100)'; }
		if (navigator.userAgent.toLowerCase().indexOf("firefox") != -1) { btn.style.MozOpacity = 1; }
		if (Safari=/a/.__proto__=='//' == true) { btn.style.opacity = 1; }

	}
	
	btn.style.cursor = 'pointer';
	
	return;

}