By default, we do not have this option. You can use the following function code. Please see the steps below:

Note: Make sure to have a complete site backup before proceeding

    1. Go to Appearance - Theme Editor.

    2. Under Select theme to edit, choose (BuddyBoss Child/whatever theme is active), then click Select.

    3. Below Theme Files, select Theme Functions (functions.php).

    4. Append the code just before the closing PHP tag “?>”:

function bb_login_custom_css() { ?>
  <style>
	#login > div.login-heading > span > a {
  font-size: 31px; /* Change this value to your desired font size */
}
      
  </style>

  add_action( 'login_enqueue_scripts', 'bb_login_custom_css');

    5. Click Update File to save the changes.

Note: Any modifications are considered as custom work already. Know more about our Support Policy here: https://www.buddyboss.com/support-policy/

Screenshots

Without Code:

With Code: