javascript - Change div background specific for the div -

i need making script project.

this how code looks like.

var thumbnails = document.getelementsbyclassname("thumbnail");  var thumbnails_lenght = thumbnails.length;    for(var i=0; i<thumbnails_lenght; i++) {  	thumbnails[i].onmouseover = function() {  		//the problem part  	};  	thumbnails[i].onmouseout = function(){  		  	};  }

*{  	margin: 0 auto;  	font-family: sans-serif;  }  .item{  	width: 240px;  	height: 240px;  	margin: 5px;  	background: #eee;  }  .thumbnail{  	width: 240px;  	height: 200px;  	background: #ddd;  }  .description{  	width: 240px;  	height: 40px;  	line-height: 20px;  	text-align: center;  	font-size: 14px;  }

<div class="item">  	<div class="thumbnail" id="1"></div>  	<div class="description">test</div>  </div>

i need make when hover on div specific class thumbnail id of thumbnail, every thumbnail div have it's id , need number.

var thumbnails = document.getelementsbyclassname("thumbnail");  var thumbnails_lenght = thumbnails.length;    for(var i=0; i<thumbnails_lenght; i++) {  	thumbnails[i].onmouseover = function(event) {  		// can id event passed handler:          alert('the id is: ' + event.target.id);  	};  	thumbnails[i].onmouseout = function(){  		  	};  }

*{  	margin: 0 auto;  	font-family: sans-serif;  }  .item{  	width: 240px;  	height: 240px;  	margin: 5px;  	background: #eee;    float: left;  }  .thumbnail{  	width: 240px;  	height: 200px;  	background: #ddd;  }  .description{  	width: 240px;  	height: 40px;  	line-height: 20px;  	text-align: center;  	font-size: 14px;  }

<div class="item">  	<div class="thumbnail" id="1"></div>  	<div class="description">test 1</div>  </div>  <div class="item">  	<div class="thumbnail" id="2"></div>  	<div class="description">test 2</div>  </div>  <div class="item">  	<div class="thumbnail" id="3"></div>  	<div class="description">test 3</div>  </div>

your event handler receive event object. object have "target" property element triggered event. can id event.target. i've modified code alert id.