Can I use
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CSS3 Box-shadow

- CR

Method of displaying an inner or outer shadow effect to elements

Chrome

  1. ✅ 4 - 9: Supported
  2. ✅ 10 - 144: Supported
  3. ✅ 145: Supported
  4. ✅ 146 - 148: Supported

Edge

  1. ✅ 12 - 144: Supported
  2. ✅ 145: Supported

Safari

  1. ◐ 3.1 - 4: Partial support
  2. ✅ 5: Supported
  3. ✅ 5.1 - 26.2: Supported
  4. ✅ 26.3: Supported
  5. ✅ 26.4 - TP: Supported

Firefox

  1. ❌ 2 - 3: Not supported
  2. ✅ 3.5 - 3.6: Supported
  3. ✅ 4 - 146: Supported
  4. ✅ 147: Supported
  5. ✅ 148 - 150: Supported

Opera

  1. ❌ 9 - 10.1: Not supported
  2. ✅ 10.5 - 124: Supported
  3. ✅ 125: Supported

IE

  1. ❌ 5.5 - 8: Not supported
  2. ✅ 9 - 10: Supported
  3. ✅ 11: Supported

Chrome for Android

  1. ✅ 145: Supported

Safari on iOS

  1. ◐ 3.2: Partial support
  2. ✅ 4 - 4.3: Supported
  3. ✅ 5 - 26.2: Supported
  4. ✅ 26.3: Supported
  5. ✅ 26.4: Supported

Samsung Internet

  1. ✅ 4 - 28: Supported
  2. ✅ 29: Supported

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

  1. ❌ 10: Not supported
  2. ✅ 11 - 12.1: Supported
  3. ✅ 80: Supported

UC Browser for Android

  1. ✅ 15.5: Supported

Android Browser

  1. ◐ 2.1 - 3: Partial support
  2. ✅ 4 - 4.4.4: Supported
  3. ✅ 145: Supported

Firefox for Android

  1. ✅ 147: Supported

QQ Browser

  1. ✅ 14.9: Supported

Baidu Browser

  1. ✅ 13.52: Supported

KaiOS Browser

  1. ✅ 2.5: Supported
  2. ✅ 3: Supported

Can be partially emulated in older IE versions using the non-standard "shadow" filter.

Resources:
Demo of various effects
MDN Web Docs - box-shadow
WebPlatform Docs
Live editor