<script type='text/javascript'>  
@Author: MisterXaker  
@Version:1.5.7  
@Site:school-ok.ru  

function Switchable(classname) {  
function getElementsByClassName(imgclass) {  
if ( document.getElementsByClassName ) {  
return document.getElementsByClassName(imgclass);  
} else {  
var nodes = document.getElementsByTagName('*'),  
tmp = [];  
for ( var i = 0; i < nodes.length; i++ ) {  
if ( new RegExp('\\b' + imgclass + '\\b').test(nodes[i].className) ) {  
tmp.push(nodes[i]);  
}  
}  
return tmp;  
}  
}  

function Next(element) {  
var next = element;  
while (next = next.nextSibling)  
if ("innerHTML" in next)  
return next;  
return element;  
}  

function getCookie(a){var b=document.cookie.match(new RegExp("(?:^|; )"+a.replace(/([\.$?*|{}\(\)\[\]\\\/\+^])/g,"\\$1")+"=([^;]*)"));return b?decodeURIComponent(b[1]):undefined}function setCookie(b,f,c){c=c||{};var i=c.expires;if(typeof i=="number"&&i){var h=new Date();h.setTime(h.getTime()+i*1000);i=c.expires=h}if(i&&i.toUTCString){c.expires=i.toUTCString()}f=encodeURIComponent(f);var a=b+"="+f;for(var e in c){a+="; "+e;var g=c[e];if(g!==true){a+="="+g}}document.cookie=a}  
var nodes = getElementsByClassName(classname);  
for (var i = 0; i < nodes.length; i++) {  
var toggler = document.createElement("A");  
toggler.href = "javascript://";  
toggler.id = "toggler" + i;  
toggler.innerHTML = getCookie("toggler" + i) == "hide" ? "+" : "-";  
toggler.onclick = function () {  
Next(this.parentNode).style.display = getCookie(this.id) == "hide" ? "" : "none";  
setCookie(this.id, getCookie(this.id) == "hide" ? "show" : "hide", {  
expires: new Date("01 Jan 2020")  
});  
this.innerHTML = getCookie(this.id) == "hide" ? "+" : "-";  
};  
Next(nodes[i]).style.display = getCookie("toggler" + i) == "hide" ? "none" : "";  
nodes[i].appendChild(toggler);  
}  
}  

Switchable("header");  
</script>