-- Per-product theme override: a product can pick its own Default/Light/
-- Steam/Custom theme for its claim page, independent of the site-wide
-- frontend theme (settings.theme). NULL means "no override, inherit the
-- site-wide theme" -- the default and only behavior before this existed.
-- background_image_path parallels settings.background_image_path but is
-- per-product, only ever shown when *this product's own* resolved theme
-- is Custom (never falls back to the site-wide background image).

ALTER TABLE products ADD COLUMN theme VARCHAR(16) NULL AFTER custom_css;
ALTER TABLE products ADD COLUMN background_image_path VARCHAR(255) NULL AFTER theme;
