The ::-moz-range-progress CSS pseudo-element represents the portion of the "track" (the groove in which the indicator aka thumb slides) of an <input> of type="range", which corresponds to values lower than the value currently selected by the thumb.
The ::-moz-range-thumb CSS pseudo-element represents the thumb, the virtual knob the user can move within the groove, or track, of an <input> of type="range" to alter its numerical value.
The ::-moz-range-track CSS pseudo-element represents the track, that is the groove in which the indicator of an <input> of type="range" slides.
The CSS ::after pseudo-element matches a virtual last child of the selected element. It is typically used to add cosmetic content to an element by using the content CSS property. This element is inline by default.
The ::-ms-fill CSS pseudo-element represents the filled-in portion of a <progress> element. This pseudo-element is non-standard and specific to Internet Explorer 10+, hence the vendor prefix.
The ::selection CSS pseudo-element applies rules to the portion of a document that has been highlighted (e.g. selected with the mouse or another pointing device) by the user.
The ::-webkit-progress-bar CSS pseudo-element represents the entire bar of a <progress> element. Normally it's only visible as the unfilled portion of the bar, since by default it's rendered below the ::-webkit-progress-value pseudo-element. It is a child of the ::-webkit-progress-inner-element pseudo-element and the parent of the ::-webkit-progress-value pseudo-element.
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.
The ::-webkit-progress-value CSS pseudo-element represents the filled-in portion of the bar of a <progress> element. It is a child of the ::-webkit-progress-bar pseudo-element.
Each element in the top layer's stack has a ::backdrop pseudo-element. This pseudo-element is a box rendered immediately below the element (and above the element below the element in the stack, if any), within the same top layer.
The ::grammar-error CSS pseudo-element represents a text segment which the browser has flagged as having grammatical error(s).
The ::-ms-fill-lower CSS pseudo-element represents the portion of the "track" (the groove in which the indicator aka thumb slides) of an <input> of type="range", which corresponds to values lower than the value currently selected by the thumb.
The ::-ms-fill-upper CSS pseudo-element represents the portion of the "track" (the groove in which the indicator aka thumb slides) of an <input> of type="range", which corresponds to values greater than the value currently selected by the thumb.
The ::-ms-thumb CSS pseudo-element represents the "thumb" that the user can move within the "groove" of an <input> of type="range" to alter its numerical value.
The ::placeholder CSS pseudo-element represents the placeholder text of a form element. This allows web developers and theme designers to customize the appearance of placeholder text.
The ::spelling-error CSS pseudo-element represents a text segment which the browser has flagged as incorrectly spelled.
The non-standard proprietary ::-webkit-input-placeholder pseudo-element represents the placeholder text of a form element. This allows web developers and theme designers to customize the appearance of placeholder text. This pseudo-class is only supported by WebKit and Blink.
The ::-webkit-slider-thumb CSS pseudo-element represents the "thumb" that the user can move within the "groove" of an <input> of type="range" to alter its numerical value.