Usage

@forms.RangeSlider(forms.RangeSliderProps{
    ID:         "price",
    Name:       "price",
    Label:      "Price Range",
    Min:        "0",
    Max:        "500",
    Step:       "10",
    ValueMin:   "100",  // initial lower thumb
    ValueMax:   "350",  // initial upper thumb
    ShowValues: true,   // show "lo – hi" badge next to label
})