// 自己紹介
function showIntroduction() {
	if ( document.getElementById("introduction").style.display == "none" ) {
		document.getElementById("introduction").style.display = "block";
		document.getElementById("introductionCTRL").style.display = "none";
	} else {
		document.getElementById("introduction").style.display = "none";
		document.getElementById("introductionCTRL").style.display = "block";
	}
}


function showOrHideTopic() {
	if ( document.getElementById("B_1_block").style.display == "none" ) {
		document.getElementById("B_1_block").style.display = "block";
	} else {
		document.getElementById("B_1_block").style.display = "none";
	}
}