Non-standard
 
      This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
Summary
The ::-webkit-progress-inner-element CSS pseudo-element represents the outermost, container pseudo-element of the <progress> element. It is the parent of the ::-webkit-progress-bar pseudo-element.
Specifications
Not part of any specification. This is a proprietary pseudo-element specific to WebKit/Blink.
Browser compatibility
| Feature | Firefox (Gecko) | Chrome | Internet Explorer | Opera | Safari | 
|---|---|---|---|---|---|
| Basic support | Not supported | (Yes) | Not supported | (Yes) | (Yes) | 
| Feature | Firefox Mobile (Gecko) | Android | IE Phone | Opera Mobile | Safari Mobile | 
|---|---|---|---|---|---|
| Basic support | Not supported | (Yes) | Not supported | (Yes) | (Yes) | 
See also
- The pseudo-elements used by WebKit/Blink to style other parts of a <progress>element:
- ::-moz-progress-bar
- ::-ms-fill