<input id="mycheck1" type="checkbox" />
<label for="mycheck1">Check box label here</label>
<br />
<input id="mycheck2" type="checkbox" checked/>
<label for="mycheck2">Check box label here</label>
<br />
<input id="mycheck3" type="checkbox" />
<label for="mycheck3">Check box label here</label>

input:checked + label{
  background: yellow;  
}