The Experimentals include experimental elements and features, mostly are not yet ready for wide use. These elements and components are limited inside spectre-exp.less before browsers fully support them. Sometimes, there are some specific browsers targeted components.
Meters represent the value within the known range.
<!-- Meter is green when low < value < high -->
<meter class="meter" value="20" min="0" max="100"></meter>
<meter class="meter" value="60" min="0" max="100" low="30" high="80"></meter>
<!-- Meter is yellow when value < low or high < value -->
<meter class="meter" value="85" min="0" max="100" low="30" high="80"></meter>
<!-- Meter is red when value < low < high < optimum or optimum < low < high < value -->
<meter class="meter" value="20" optimum="90" min="0" max="100" low="30" high="80"></meter>
The Progress indicates the progress completion of a task.
<progress class="progress" value="25" max="100"></progress>
Sliders are for selecting values from ranges.
<input class="slider" type="range" min="0" max="100" value="50" />