Variant variables become available alongside product variables when a specific product variant is selected by the customer. They let you display information specific to the chosen size, colour, or other option rather than the product as a whole.
variant.name — The name of the selected variant, typically a combination of option values such as "Red / XL" or "500ml".
variant.quantity — The number of units currently in stock for the selected variant. Useful for scarcity messaging like "Only {{ variant.quantity }} left!"