specify light mode for civicrm.css to fix Standalone logo in Greenwich

[ufundo]

Overview

Tell browser that our non-Riverlea themes dont have darkmode.

Before

• system components and SVG will respond if the user has set dark mode (in their browser/OS)
• this causes a particular issue with the logo on Standalone login page if your theme is set to Greenwich and your browser asks for dark mode => you get a dark mode logo (white) on the fixed white background

After

• in Greenwich, everything inside .crm-container CiviCRM always stays in light mode
• in Riverlea this gets overridden and handled as per Riverlea's dark mode setting

Comments

I wonder if there is a risk that someone is using Greenwich but has custom components that do respond to dark mode?

[civibot]

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[ufundo]

Pointing at 6.1 because that's where the SVG logo is introduced which is the symptom I'm trying to fix