/* Submenu collapsible styles */
.nav-submenu {
    display: none;
    padding-left: 15px;
}

.nav-submenu.expanded {
    display: block;
}

.nav-parent {
    position: relative;
}

.nav-parent::after {
    content: ' ▶';
    font-size: 0.8em;
    margin-left: 5px;
}

.nav-parent.expanded::after {
    content: ' ▼';
}

.nav-subitem {
    font-size: 0.9em;
    opacity: 0.9;
    padding-left: 10px;
}