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<h1>CSS reference</h1>
<h2>CSS 개요</h2>
<h2>CSS 기본 서식</h2>
<h2>CSS 적용방법</h2>

<h1>CSS dictionary</h1>
<h2>박스모델</h2>
<h2>배치</h2>
<h2>사용자 인터페이스 </h2>

body {
    counter-reset:section;
}
h1 {
    counter-reset:subsection;
}
h1:before
{
    counter-increment:section;
    content:"Section " counter(section) ". ";
}
h2:before 
{
    counter-increment:subsection;
    content:counter(section) "." counter(subsection) " ";
}