Big plus and minus chars in HTML list

The UL list-style can be names or use (a) character(s)

• Unicode Character “➖” (U+2796)
• Unicode Character “➕” (U+2795)

ul.tree li.container {
  list-style-type: "\2795";
}

ul.tree li.container.open {
    list-style-type: "\2796";
}