Select foreign key matching multiple criteria in a joining table (SQLITE)

Question

Preface: this is all in a fiddle here https://www.db-fiddle.com/f/pMLFrz59aeL7B2jUsmTt9X/1

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I have a table that contains items (item #100, item #101...) that each have various attributes (color, type, size). Because the set of attributes are not consistent (e.g. in the table below, item #100 is a hat, which don't typically have a size), I created a map of the items to the attribute type and attribute value for each of the items.

Item	Type	Value
Item #100	Color	Red
Item #100	Type	Hat
Item #101	Color	Blue
Item #101	Size	S
Item #101	Type	T-Shirt

Snip

However I am now struggling to retrieve items by an arbitrary set of multiple criteria — for example, I am unsure of how to select all items that have:

Attribute type Size with attribute value s

AND

Attribute type Color, attribute value Blue

(which, for the example, the query would return Item #101 and Item #103)

I successfully retrieved the rows with selecting all of the individual criteria and then Intersecting them together (e.g. select everything of size "s" intersected with select everything of color "blue"). That didn't seem like a good solution as the full set of criteria to query by will change (sometimes it will only by one attribute, sometimes it will be by multiple)

I am relatively new at all of this, but reading through sqlite's documentation about indices felt in the right neighborhood...