::-webkit-meter-suboptimum-value

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.

The ::-webkit-meter-suboptimum-value pseudo-element styles the <meter> element when the value attribute falls outside of the low-high range and is not equivalent to the optimum value.

Yellow is the default color.

Syntax

css
::-webkit-meter-suboptimum-value {
  /* ... */
}

Examples

This example will only work in browsers based on WebKit or Blink.

HTML

html
Normal:
<meter min="0" max="10" low="3" high="7" optimum="6" value="2">
  Score 2/10
</meter>
<br />
Styled:
<meter id="styled" min="0" max="10" low="3" high="7" optimum="6" value="2">
  Score 2/10
</meter>

CSS

css
body {
  font-family: monospace;
}

.safari meter {
  /* Reset the default appearance for Safari only */
  /* .safari class is added via JavaScript */
  -webkit-appearance: none;
}

#styled::-webkit-meter-suboptimum-value {
  background: linear-gradient(to bottom, #ff7, #990 45%, #990 55%, #ff7);
  height: 100%;
  box-sizing: border-box;
}

JavaScript

js
// Safari requires <meter> elements to have an `appearance` of `none` for custom styling
// using `::-webkit-meter-*` selectors, but `appearance: none` breaks rendering on Chrome.
// Therefore, we must check if the browser is Safari-based.

const is_safari =
  navigator.userAgent.includes("AppleWebKit/") &&
  !navigator.userAgent.includes("Chrome/");

if (is_safari) {
  document.body.classList.add("safari");
}

Result

Specifications

Not part of any standard.

Browser compatibility

BCD tables only load in the browser

See also

The pseudo-elements used by WebKit/Blink to style other parts of a <meter> element are as follows: