Can't filter by nodes in field with type jsonb

Question

Table has two columns: id and data.

Column data has type jsonb

json :

  "weight": {
    "qty": 300,
    "unit": {
      "name": "gram",
      "title": {
        "en": "g"
      }
    }
  

I want to filter by json's nodes weight and qty.

Here query:

SELECT
(product.data #>'{weight,qty}') AS weight
FROM product 
WHERE weight = 300
order by id desc

But I get error:

ERROR:  column "weight" does not exist
LINE 4: WHERE weight = 123
              ^
SQL state: 42703
Character: 70