Vertical counter

 <!-- put all in a wrapper:-->
<div class="wrap" role="group" aria-label="slider with ruler" style="--min: 0; --val: 18; --max: 36">
  <!-- slider:-->
  <input id="r" type="range" list="l" max="36"/>
  <!-- value display:-->
  <output for="r"></output>
  <!-- ruler:-->
  <datalist id="l">
    <option value="0" style="--idx: 0" label="0"></option>
    <option value="1" style="--idx: 1"></option>
    <option value="2" style="--idx: 2"></option>
    <option value="3" style="--idx: 3"></option>
    <option value="4" style="--idx: 4"></option>
    <option value="5" style="--idx: 5"></option>
    <option value="6" style="--idx: 6" label="6"></option>
    <option value="7" style="--idx: 7"></option>
    <option value="8" style="--idx: 8"></option>
    <option value="9" style="--idx: 9"></option>
    <option value="10" style="--idx: 10"></option>
    <option value="11" style="--idx: 11"></option>
    <option value="12" style="--idx: 12" label="12"></option>
    <option value="13" style="--idx: 13"></option>
    <option value="14" style="--idx: 14"></option>
    <option value="15" style="--idx: 15"></option>
    <option value="16" style="--idx: 16"></option>
    <option value="17" style="--idx: 17"></option>
    <option value="18" style="--idx: 18" label="18"></option>
    <option value="19" style="--idx: 19"></option>
    <option value="20" style="--idx: 20"></option>
    <option value="21" style="--idx: 21"></option>
    <option value="22" style="--idx: 22"></option>
    <option value="23" style="--idx: 23"></option>
    <option value="24" style="--idx: 24" label="24"></option>
    <option value="25" style="--idx: 25"></option>
    <option value="26" style="--idx: 26"></option>
    <option value="27" style="--idx: 27"></option>
    <option value="28" style="--idx: 28"></option>
    <option value="29" style="--idx: 29"></option>
    <option value="30" style="--idx: 30" label="30"></option>
    <option value="31" style="--idx: 31"></option>
    <option value="32" style="--idx: 32"></option>
    <option value="33" style="--idx: 33"></option>
    <option value="34" style="--idx: 34"></option>
    <option value="35" style="--idx: 35"></option>
    <option value="36" style="--idx: 36" label="36"></option>
  </datalist>
</div>

/* ===== MIXINS FOR SLIDER TRACK & THUMB ===== */
/* fix track height */
/* ===== GENERIC STYLES ===== */
html, body, div, datalist, output, section {
  display: grid;
}

html {
  height: 100%;
}

body {
  overflow-x: hidden;
  /* because range input takes up space horizontally before rotation */
  background: #1f1f1f;
}
@supports (line-height: tan(45deg)) {
  body {
    --trig: none ;
  }
}
@supports (color: color-mix(in lch, red 1%, tan)) {
  body {
    --cmix: none ;
  }
}

/* ===== SLIDER WRAPPER WITH VISUAL TRACK & GLOW ===== */
.wrap {
  --rng: calc(var(--max) - var(--min));
  /* range between max and min values */
  --prg: calc((var(--val) - var(--min))/var(--rng));
  /* decimal progress */
  --prc: calc(var(--prg)*100%);
  /* percentage progress */
  --pos: calc(var(--val)*1rem);
  /* position from 1st ruler line (from val = min) */
  grid-gap: 1.25rem;
  /* space out ruler, track, thumb, output value */
  grid-template-columns: -webkit-max-content 0.1875rem 1.25rem -webkit-max-content;
  grid-template-columns: max-content 0.1875rem 1.25rem max-content;
  place-self: center;
  /* put in the middle of body grid cell along both axes */
  color: #f43e75;
  /*fallback  */
  font: 1em trebuchet ms, ubuntu, verdana, arial, sans-serif;
  transition: 0.35s;
  /* focus/ hover transition */
  /* make sepia only when range input not focused */
  /* making up visual track & glow */
  /* ----- Glow ----- */
  /* ----- Visual track ----- */
}
@supports (color: color-mix(in lch, red 1%, tan)) {
  .wrap {
    /* if color-mix is supported */
    color: color-mix(in lch, #f43e75 var(--prc), #daff47);
  }
}
.wrap:not(:focus-within):not(:hover) {
  filter: sepia(1);
}
.wrap::before, .wrap::after {
  --pos-x: calc(100% + 1.875rem);
  /* x position of middle rounding circle centre */
  --pos-y: calc(var(--pos) + 7.4375rem);
  /* y position considering vertical overflow  */
  grid-area: 1/1/span 1/span 2;
  /* cover first two columns */
  place-self: center end;
  /* attach to middle right of rightmost cell they cover */
  z-index: 1;
  /* both on top of ruler */
  width: 5.5625rem;
  /* make it wide enough to contain the glow */
  height: calc(100% + 2*7.4375rem);
  /* long enough to contain the glow at min/ max */
  transform: scaley(-1);
  /* ugh... maybe I could have flipped the gradients instead */
  content: "";
}
.wrap::before {
  --sl: transparent calc(100% + -.5px), red calc(100% + .5px);
  /* mask gradient stop list */
  background: radial-gradient(circle 7.4375rem at var(--pos-x) var(--pos-y), currentcolor 4.0625rem, transparent);
  /* how mask compositing works:
   * https://css-tricks.com/mask-compositing-the-crash-course/ */
  -webkit-mask: radial-gradient(circle 4.25rem at var(--pos-x) var(--pos-y), var(--sl)), radial-gradient(circle 4.4375rem at 0 0, var(--sl)) 100% calc(var(--pos-y) + -1*5.9686681932rem)/4.4375rem 2.9199240082rem no-repeat, radial-gradient(circle 4.4375rem at 0 100%, var(--sl)) 100% calc(var(--pos-y) + 3.048744185rem)/4.4375rem 2.9199240082rem no-repeat;
  -webkit-mask-composite: source-out, source-over;
          mask: radial-gradient(circle 4.25rem at var(--pos-x) var(--pos-y), var(--sl)) subtract, radial-gradient(circle 4.4375rem at 0 0, var(--sl)) 100% calc(var(--pos-y) + -1*5.9686681932rem)/4.4375rem 2.9199240082rem no-repeat add, radial-gradient(circle 4.4375rem at 0 100%, var(--sl)) 100% calc(var(--pos-y) + 3.048744185rem)/4.4375rem 2.9199240082rem no-repeat;
}
.wrap::after {
  --sl: /* mask gradient stop list */
  	transparent calc(4.25rem + -.5px),
  	red calc(4.25rem + .5px) calc(100% + -.5px),
  	transparent calc(100% + .5px);
  background: linear-gradient(currentcolor calc(var(--pos-y) + 6rem), transparent calc(var(--pos-y) + 2*6rem)) #666;
  -webkit-mask: linear-gradient(red calc(var(--pos-y) + -1*5.9686681932rem + .5px), transparent 0 calc(var(--pos-y) + 5.9686681932rem + -.5px), red 0) 100%/0.1875rem 100%, radial-gradient(circle 4.4375rem at var(--pos-x), var(--sl)) 100% calc(var(--pos-y) + -1*3.048744185rem + -.5px)/100% calc(2*3.048744185rem + 1px), radial-gradient(circle 4.4375rem at 0 0, var(--sl)) 100% calc(var(--pos-y) + -1*5.9686681932rem)/4.4375rem 2.9199240082rem, radial-gradient(circle 4.4375rem at 0 100%, var(--sl)) 100% calc(var(--pos-y) + 3.048744185rem)/4.4375rem 2.9199240082rem;
          mask: linear-gradient(red calc(var(--pos-y) + -1*5.9686681932rem + .5px), transparent 0 calc(var(--pos-y) + 5.9686681932rem + -.5px), red 0) 100%/0.1875rem 100%, radial-gradient(circle 4.4375rem at var(--pos-x), var(--sl)) 100% calc(var(--pos-y) + -1*3.048744185rem + -.5px)/100% calc(2*3.048744185rem + 1px), radial-gradient(circle 4.4375rem at 0 0, var(--sl)) 100% calc(var(--pos-y) + -1*5.9686681932rem)/4.4375rem 2.9199240082rem, radial-gradient(circle 4.4375rem at 0 100%, var(--sl)) 100% calc(var(--pos-y) + 3.048744185rem)/4.4375rem 2.9199240082rem;
  -webkit-mask-repeat: no-repeat;
          mask-repeat: no-repeat;
}

/* ===== SLIDER WITH VALUE ===== */
[type=range] {
  --sel: 0;
  /* initial selection status: false (0) */
  place-self: center;
  /* put it in middle of grid cell along both directions */
  /* length based on ruler & thumb dimensions */
  width: calc(var(--max)*1rem + 6rem);
  height: 1.25rem;
  transform: rotate(-90deg);
  /* we have no better options for vertical sliders */
  background: transparent;
  /* get rid of default white in WebKit */
  font: inherit;
  /* override default 13.333px, ugh */
  cursor: pointer;
  /* make it obvious it's interactive */
  /* looks ugly AND ***we've already set focus styles*** */
  /* change selection status to true (1) */
  /* set track & thumb styles */
  /* ----- Value display ----- */
}
[type=range], [type=range]::-webkit-slider-runnable-track, [type=range]::-webkit-slider-thumb {
  -webkit-appearance: none;
}
[type=range]:focus {
  outline: none;
}
[type=range]:hover, [type=range]:focus {
  --sel: 1 ;
}
[type=range]::-webkit-slider-runnable-track {
  height: 100%;
}
[type=range]::-moz-range-track {
  height: 100%;
}
[type=range]::-webkit-slider-thumb {
  /* only add a top margin if the m flag is non-zero */
  margin-top: -2.375rem;
  /* we use --sel to flip between normal & hover/ focus styles
   * detailed explanation 
   * https://css-tricks.com/dry-switching-with-css-variables-the-difference-of-one-declaration/ */
  --shl: 0 0 0 calc((1 - .375*var(--sel))*1rem) /* slightly decrease spread in hover/ focus case */
  			 hsla(0, 0%, 19%, var(--sel)) /* non-zero shadow alpha only in hover/ focus case */;
  box-sizing: border-box;
  border: none;
  /* get rid of Firefox border */
  padding: 0.625rem;
  /* to add space around bg limited to content-box */
  width: 6rem;
  height: 6rem;
  /* aspect-ratio: 1 doesn't work here in Firefox */
  border-radius: 50%;
  box-shadow: 0 0 0.5px black, inset 0 0 1px 1px rgba(255, 255, 255, 0.05), inset var(--shl), inset 0 0 0 calc(.5*0.42*(6rem + -2*0.625rem) + 0.625rem) #1f1f1f, 0.25rem -0.25rem 0.25rem #2a2a2a, -0.25rem 0.25rem 0.75rem #090909, var(--shl), 0.75rem -0.75rem 0.75rem #2a2a2a, -0.75rem 0.75rem 1.25rem #090909;
  background: repeating-conic-gradient(from 60deg, transparent 0%, silver 1deg 59deg, transparent 60deg 50%) 0/42% 100% space content-box #1f1f1f;
  -webkit-transition: box-shadow 0.35s;
  transition: box-shadow 0.35s;
  cursor: ns-resize;
}
[type=range]::-moz-range-thumb {
  /* only add a top margin if the m flag is non-zero */
  /* we use --sel to flip between normal & hover/ focus styles
   * detailed explanation 
   * https://css-tricks.com/dry-switching-with-css-variables-the-difference-of-one-declaration/ */
  --shl: 0 0 0 calc((1 - .375*var(--sel))*1rem) /* slightly decrease spread in hover/ focus case */
  			 hsla(0, 0%, 19%, var(--sel)) /* non-zero shadow alpha only in hover/ focus case */;
  box-sizing: border-box;
  border: none;
  /* get rid of Firefox border */
  padding: 0.625rem;
  /* to add space around bg limited to content-box */
  width: 6rem;
  height: 6rem;
  /* aspect-ratio: 1 doesn't work here in Firefox */
  border-radius: 50%;
  box-shadow: 0 0 0.5px black, inset 0 0 1px 1px rgba(255, 255, 255, 0.05), inset var(--shl), inset 0 0 0 calc(.5*0.42*(6rem + -2*0.625rem) + 0.625rem) #1f1f1f, 0.25rem -0.25rem 0.25rem #2a2a2a, -0.25rem 0.25rem 0.75rem #090909, var(--shl), 0.75rem -0.75rem 0.75rem #2a2a2a, -0.75rem 0.75rem 1.25rem #090909;
  background: repeating-conic-gradient(from 60deg, transparent 0%, silver 1deg 59deg, transparent 60deg 50%) 0/42% 100% space content-box #1f1f1f;
  -moz-transition: box-shadow 0.35s;
  transition: box-shadow 0.35s;
  cursor: ns-resize;
}
[type=range] + output {
  place-self: end;
  /* put it in bottom right corner of grid cell it's in */
  place-content: center;
  /* place its content in the middle along both directions */
  margin-left: 0.25em;
  /* space it out a bit from oversized thumb on its left */
  width: 1.25em;
  /* make it wide enough to accommodate all possible values */
  aspect-ratio: 1;
  /* make it square */
  transform: translatey(calc(50% - var(--pos)));
  /* move vertically with slider value */
  font-size: 6.25rem;
  /* blow up font size */
  font-weight: 100;
  /* ends up too thick, make it thinner */
  line-height: 1.25;
  /* now why the fuck didn't I just use the shorthand here */
  counter-reset: val var(--val);
  /* set counter to slider value */
  /* in order to be able to use its (numeric integer) value for the ::after */
  /* content: var(--val) works only if --val is string */
}
[type=range] + output::after {
  content: counter(val);
}

/* ===== RULER ===== */
datalist {
  grid-area: 1/1;
  /* occupy cell at intersection between 1st row & 1st column */
  /* make its gri have max value + 1 rows (because 1st value is 0) of unit height */
  grid-template-rows: repeat(calc(var(--max) + 1), 1rem);
  margin: -0.5rem 0;
}

option {
  /* absolute value of difference between the option index idx & current slider value val 
   * https://css-tricks.com/using-absolute-value-sign-rounding-and-modulo-in-css-today/ */
  --abs: max(var(--val) - var(--idx), var(--idx) - var(--val));
  --rel: calc(var(--abs)/6);
  /* relative value to number of ruler marks affected */
  --sel: max(0, 1 - var(--rel)*var(--rel));
  /* try to compensate for no trig with circular dist */
  --off: calc(var(--sel)*-2.375rem);
  /* thumb-caused offset */
  grid-row: calc(var(--max) + 1 - var(--idx));
  /* visually reverse row order */
  align-self: center;
  /* ensure big text is vertically in the middle of containing cells */
  padding-right: 0.75em;
  /* leave space for ruler marks */
  transform: translate(var(--off));
  /* apply thumb caused offset via transform */
  background: linear-gradient(hsl(0, 0%, var(--lum, 32%)) 0 0) 100%/0.5em 2px no-repeat;
  /* text alpha depends on distance from thumb */
  color: hsla(0, 0%, 93%, calc(1 - .0625*var(--abs)));
  font-size: 2rem;
  text-align: right;
  transition: 0.2s ease-out;
  /* make major ruler markings brighter */
}
@supports (top: calc(sin(5deg)*1px)) {
  option {
    /* if we have trigonometry in CSS */
    --sel: max(0, 1 - var(--rel));
    /* linear selection value */
    /* make the ruler mark distribution around thumb follow a cos wave */
    --off: calc(.5*(1 - cos(var(--sel)*180deg))*-2.375rem) ;
  }
}
option[label] {
  --lum: 90% ;
}

/* ===== SUPPORT INFO BOXES ===== */
section {
  grid-gap: 0.625rem;
  /* some space between boxes if there are more */
  position: fixed;
  /* take out of document flow */
  z-index: 2;
  /* on top of everything else */
  inset: auto 0 0;
  /* attach to parent's padind-box edges except top */
  padding: 0.625rem;
  /* set padding equal to gap */
  font: clamp(.625em, 2.5vw, 1.25em)/1.25 trebuchet ms, ubuntu, verdana, arial, sans-serif;
}

.box {
  margin: 0;
  /* override browser default */
  border-left: solid 5px var(--c0, #dc3055);
  padding: inherit;
  /* pad info boxes as well */
  background: var(--c1, #851d40);
  color: white;
  /* modify palette for warn */
}
.box--warn {
  --c0: #fd8721;
  --c1: #c34915 ;
}
.box--list {
  display: var(--list);
}
.box--trig {
  display: var(--trig);
}
.box--cmix {
  display: var(--cmix);
}

code, kbd {
  padding: 2px;
  background: rgba(0, 0, 0, 0.2);
  font: 1.1em/1.2 ubuntu mono, consolas, monaco, monospace;
}

/* This is all the JS used and it does only 2 things: */

/* 1. datalist option render support test (for support info box) */
addEventListener('load', e => {
	if(+document.querySelector('option').getBoundingClientRect().width)
		document.body.style.setProperty('--list', 'none')
})

/* 2. update the --val custom property on dragging slider thumb */
addEventListener('input', e => {
	let _t = e.target;
	_t.parentNode.style.setProperty('--val', +_t.value)
})

/* Absolutely no JS is needed for creating the look of the slider. */