//preload
function preload(imgs){
 for(var i = 0; i < imgs.length; i++){
   var imgObj = new Image();
   imgObj.src = imgs[i];
 }
}

//chTab

function chTab1(){
		preload(["http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/arrow_gray.gif"]);
		document.getElementById("chbox1").style.display = "none";
		document.getElementById("chbox2").style.display = "block";
		document.getElementById("chT1").style.borderBottom = "1px solid #ccc";
		document.getElementById("chT2").style.borderBottom = "1px solid #fff";
		document.getElementById("chboxL1").style.color = "#28419B";
		document.getElementById("chboxL2").style.color = "#333";
		document.getElementById("chT1").style.background = "#f7f7f7 url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif')";
		document.getElementById("chT2").style.background = "#fff url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif')";
}

function chTab2(){
		preload(["http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/arrow_gray.gif"]);
		document.getElementById("chbox2").style.display = "none";
		document.getElementById("chbox1").style.display = "block";
		document.getElementById("chT1").style.borderBottom = "1px solid #fff";
		document.getElementById("chT2").style.borderBottom = "1px solid #ccc";
		document.getElementById("chboxL1").style.color = "#333";
		document.getElementById("chboxL2").style.color = "#28419B";
		document.getElementById("chT1").style.background = "#fff url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif')";
		document.getElementById("chT2").style.background = "#f7f7f7 url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif')";
}

function chTab3(){
		preload(["http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/arrow_gray.gif"]);
		document.getElementById("chbox3").style.display = "none";
		document.getElementById("chbox4").style.display = "block";
		document.getElementById("chT3").style.borderBottom = "1px solid #ccc";
		document.getElementById("chT4").style.borderBottom = "1px solid #fff";
		document.getElementById("chboxL3").style.color = "#28419B";
		document.getElementById("chboxL4").style.color = "#333";
		document.getElementById("chT3").style.background = "#f7f7f7 url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif')";
		document.getElementById("chT4").style.background = "#fff url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif')";
}

function chTab4(){
		preload(["http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif", "http://www.sanspo.com/css/news_v20080602000/images/arrow_gray.gif"]);
		document.getElementById("chbox4").style.display = "none";
		document.getElementById("chbox3").style.display = "block";
		document.getElementById("chT3").style.borderBottom = "1px solid #fff";
		document.getElementById("chT4").style.borderBottom = "1px solid #ccc";
		document.getElementById("chboxL3").style.color = "#333";
		document.getElementById("chboxL4").style.color = "#28419B";
		document.getElementById("chT3").style.background = "#fff url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox1tab.gif')";
		document.getElementById("chT4").style.background = "#f7f7f7 url('http://www.sanspo.com/css/news_v20080602000/images/title/chbox2tab.gif')";
}