How to use the id selector

Question

I put it in a example.css and then on my html I try it.
it did not work
but the class selector work.
ps. I seperate my content and style

Answer 1

<div id="divOne">
</div>

/****example.css **/

#divOne{
color: #FFFFFF;
background-color:000000;
}

Answer 2

yes I already try it.
html
<div id="sample">
<p> test para </p>
<p> test paragraph </p>
</div>
and the css file
#sample {color: blue; background-color: gray;}
and it wont work

Answer 3

do you linked the example.css on header of your page

Answer 4

yes. <link rel="sheetstyle" href="example.css">
and it work on class and now I try the id selector again and it work like class.
it should be <p id="sample"> so it just like a class selector