Question about non-numeric value error

Hello!

Yesterday, I migrated my WordPress website (which uses the Inovado theme) to Pantheon (pantheon.io). In the admin screen, the site is throwing an error:

Warning: A non-numeric value encountered in /srv/bindings/e27296fc0e764c1fa5ed74827c036982/code/wp-content/themes/inovado/framework/inc/customcss.php on line 74

Here is line #74 in that php file:

$style_headerheight_minus = $data[‘style_headerheight’]-3;

The Pantheon host is running PHP
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Manage your site’s PHP version via the pantheon.yml configuration file.
LifePathsResearch – Current PHP Settings:
DevelopmentPHP 7.2
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Can you suggest what I might do to remove that error?

Thank you!
Judy Wilson

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