Install it using: $ npm install gitbook-plugin-tocstyles
Be sure too activate the option from the book.json file :
{
"plugins" : ["tocstyles"]
,"pluginsConfig":
{
"tocstyles" : [ "", "cjk-ideographic", "decimal-leading-zero" ]
}
}The tocstyles array in pluginsConfig defines CSS list-style-type properties for each level of the TOC hierarchy.
