Can’t get options with $data[‘variable’]

This is actually a PHP question, and not a WordPress question.

The issue is that global variables don’t pass through the include()/require() call from the template file into header.php.

The solution is to define $data after you globalize it.

Without knowing your options framework or your Theme specifically, I can only answer in general terms; that said, you would likely define $data like so:

global $data;
$data = get_option( 'some_option' );

or

global $data;
$data = framework_get_options();

Hint: take a look at /css/styles.php to see how your framework/Theme does this, specifically.