makeSeparator = (spColor = 'grey', spWidthPctg = 100, spHeight = 30, spMarginPctg = 10) => {
return htl.svg`<svg width=${width*spWidthPctg/100} height=${spHeight + ""} viewBox="0 0 ${width*spWidthPctg/100} ${spHeight}">
<rect width="100%" height=${100-2*spMarginPctg + "%"} fill=${spColor} />
</svg>`
}