【WordPress】Hタグに自動で番号を振る

/* タイトルに自動で章番号を表記 */
body {
counter-reset: chapter;
}
h2 {
counter-reset: sub-chapter;
}
h3 {
counter-reset: section;
}
.article h2::before {
counter-increment: chapter;
content: counter(chapter) “. “;
}
.article h3::before {
counter-increment: sub-chapter;
content: counter(chapter) “-” counter(sub-chapter) “. “;
}
.article h4::before {
counter-increment: section;
content: “(” counter(section) “) “;
}