Can I use
?

background-position-x & background-position-y

- UNOFF

CSS longhand properties to define x or y positions separately.

Chrome

  1. ✅ 4 - 136: Supported
  2. ✅ 137: Supported
  3. ✅ 138 - 140: Supported

Edge

  1. ✅ 12 - 136: Supported
  2. ✅ 137: Supported

Safari

  1. ✅ 3.1 - 18.4: Supported
  2. ✅ 18.5: Supported
  3. ✅ 26.0 - TP: Supported

Firefox

  1. ❌ 2 - 48: Not supported
  2. ✅ 49 - 138: Supported
  3. ✅ 139: Supported
  4. ✅ 140 - 142: Supported

Opera

  1. ❌ 9 - 12.1: Not supported
  2. ✅ 15 - 116: Supported
  3. ✅ 117: Supported

IE

  1. ✅ 5.5 - 10: Supported
  2. ✅ 11: Supported

Chrome for Android

  1. ✅ 137: Supported

Safari on iOS

  1. ✅ 3.2 - 18.4: Supported
  2. ✅ 18.5: Supported
  3. ✅ 26.0: Supported

Samsung Internet

  1. ✅ 4 - 27: Supported
  2. ✅ 28: Supported

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

  1. ❌ 10 - 12.1: Not supported
  2. ✅ 80: Supported

UC Browser for Android

  1. ✅ 15.5: Supported

Android Browser

  1. ✅ 2.1 - 4.4.4: Supported
  2. ✅ 137: Supported

Firefox for Android

  1. ✅ 139: Supported

QQ Browser

  1. ✅ 14.9: Supported

Baidu Browser

  1. ✅ 13.52: Supported

KaiOS Browser

  1. ❌ 2.5: Not supported
  2. ✅ 3: Supported

A workaround for the lack of support in Firefox 31 - Firefox 48 is to use CSS variables. See this Stack Overflow answer for an example.

Resources:
Firefox implementation bug
MDN Web Docs - background-position-x
MDN Web Docs - background-position-y
Blog post on background-position-x & y properties