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README.md

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 # Normalization of a CSS z-index value to a 32-bit floating-point number
 
+[![crate](https://img.shields.io/crates/v/normalize-css-z.svg)](https://crates.io/crates/normalize-css-z)
+[![documentation](https://docs.rs/normalize-css-z/badge.svg)](https://docs.rs/normalize-css-z)
+[![build status](https://github.com/sjinno/normalize-css-z/actions/workflows/rust.yml/badge.svg)](https://github.com/sjinno/normalize-css-z/actions)
+
 ## Origin
 
 I struggled to map CSS z-index values to 32-bit floating-point numbers between 0.0 and 1.0 because dividing a large number by another large number, such as 2_147_483_646.0 / 2_147_483_647.0, does not yield precise results.