var mTimer;
var y = 0;
var x=true;
var default_caption = 'Introduceti un cuvant cheie';

function init_search(){
	x=true;
	document.f.query.value=default_caption;
}

function clear_search(x){
	if(x==false){
		return false;
	}else{
		document.f.query.value = "";
		return false;
	}
}

function check(){
	if((document.f.query.value == "") || (document.f.query.value == default_caption)){
		document.f.query.value = "";
		y = 0;
		mTimer = setTimeout('flash_red();',100);
		return false;
	}
	return true;
}

function flash_red(){
	if(y<10){
		mTimer = setTimeout('flash_white();',100);
		document.getElementById('query').className = 'red';
		y++;
	}else{
		document.getElementById('query').className = '';
		document.f.query.focus();
	}
}

function flash_white(){
	if(y<10){
		mTimer = setTimeout('flash_red();',100);
		document.getElementById('query').className = '';
		y++;
	}else{
		document.getElementById('query').className = '';
		document.f.query.focus();
	}
}
<!-- 
 
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