Error Line 16 column 125: document type does not allow element "input" here; missing one of "p", "h1", "h2", "h3", "h4", "h5", "h6", "div", "pre", "address", "fieldset", "ins", "del" start-tag.
...;" onblur="this.value='Szukaj...';" />

The mentioned element is not allowed to appear in the context in which you've placed it; the other mentioned elements are the only ones that are both allowed there and can contain the element mentioned. This might mean that you need a containing element, or possibly that you've forgotten to close a previous element.

One possible cause for this message is that you have attempted to put a block-level element (such as "<p>" or "<table>") inside an inline element (such as "<a>", "<span>", or "<font>").

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<div id="header">
 
		<form action="#">
 
			<input type="text" name="search" id="search" value="Szukaj..." onfocus="this.value='';" onblur="this.value='Szukaj...';" />
 
		</form>
 
		<h1>Suchy.jogger.pl</h1>
		<h3>| mój kawałek internetu</h3>
 
 
	</div>
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