Hi Sijay-
Thanks for reaching out, this looks like a bug in the collapsible menu’s CSS. The [+] signs that expand and collapse the sub-menus are offsetting the text by 32 pixels, so we’ll need to use half that value’s padding to make them correctly centered.
I’ve submitted a bug report to our developers about this, but in the meantime you can fix your menu with this Custom CSS code. Navigate to Customize > Advanced > Custom JS & CSS and paste this into your Custom Theme CSS:
.navbar-nav.sm-collapsible a.has-submenu { padding-right: 16px; }