font CSS property

font:
  1.2rem "Fira Sans",
  sans-serif;

font:
  italic 1.2rem "Fira Sans",
  serif;

font: italic small-caps bold 16px/2 cursive;

font: small-caps bold 24px/1 sans-serif;

font: caption;

<section id="default-example">
  <q id="example-element">
    Prejudices, it is well known, are most difficult to eradicate from the heart
    whose soil has never been loosened or fertilised by education: they grow
    there, firm as weeds among stones.
  </q>
</section>

@font-face {
  font-family: "Fira Sans";
  src:
    local("FiraSans-Regular"),
    url("/shared-assets/fonts/FiraSans-Regular.woff2") format("woff2");
  font-weight: normal;
  font-style: normal;
}

@font-face {
  font-family: "Fira Sans";
  src:
    local("FiraSans-Italic"),
    url("/shared-assets/fonts/FiraSans-Italic.woff2") format("woff2");
  font-weight: normal;
  font-style: italic;
}

section {
  margin-top: 10px;
  font-size: 1.1em;
}

/* font-size font-family */
font: 1.2em sans-serif;

/* font-size/line-height font-family */
font: 1.2em/2 "Fira Sans", sans-serif;

/* font-style font-weight font-size font-family */
font: italic bold 1.2em monospace;

/* font-width font-variant font-size font-family */
font: ultra-condensed small-caps 1.2em Montserrat, Helvetica, sans-serif;

/* system font */
font: caption;

p {
  font: 12px / 14px sans-serif;
}

<p>
  This is a paragraph of sans-serif text. The font-size is small, at just 12px.
  If this text wraps, the line height is pretty tight at 14px, so this may be
  difficult to read.
</p>

p {
  font: bold italic large / 1.6 serif;
}

<p>
  In this example, we set the font weight to bold, the font style to italic, the
  font size to large, the line height to 1.6, and the font family to serif.
</p>

p {
  font: status-bar;
  line-height: 1.6;
}

<p>
  <a
    href="/%20The%20font%20should%20be%20the%20same%20
family%20and%20size%20and%20the%20text%20in%20the%20example."
    >Hover or focus this text. The font should be the same family and size and
    the text in your status bar.</a
  >
</p>

const aElem = document.querySelector("a");
aElem.addEventListener("click", function (e) {
  e.preventDefault();
  return false;
});

<p>
  Change the radio buttons below to see the generated shorthand and its effect.
</p>
<form action="createShortHand()">
  <div class="cf">
    <div class="setPropCont">
      font-style<br />
      <input
        type="radio"
        id="font-style-none"
        name="font_style"
        checked
        value="" />
      <label for="font-style-none">omit value</label><br />
      <input
        type="radio"
        id="font-style-normal"
        name="font_style"
        value="normal" />
      <label for="font-style-normal">normal</label><br />
      <input
        type="radio"
        id="font-style-italic"
        name="font_style"
        value="italic" />
      <label for="font-style-italic">italic</label><br />
      <input
        type="radio"
        id="font-style-oblique"
        name="font_style"
        value="oblique" />
      <label for="font-style-oblique">oblique</label>
    </div>

    <div class="setPropCont">
      font-variant<br />
      <input
        type="radio"
        id="font-variant-none"
        name="font_variant"
        checked
        value=" " />
      <label for="font-variant-none">omit value</label><br />
      <input
        type="radio"
        id="font-variant-normal"
        name="font_variant"
        value="normal" />
      <label for="font-variant-normal">normal</label><br />
      <input
        type="radio"
        id="font-variant-small-caps"
        name="font_variant"
        value="small-caps" />
      <label for="font-variant-small-caps">small-caps</label>
    </div>

    <div class="setPropCont">
      font-weight<br />
      <input type="radio" id="font-weight-none" name="font_weight" value="" />
      <label for="font-weight-none">omit value</label><br />
      <input
        type="radio"
        id="font-weight-normal"
        checked
        name="font_weight"
        value="400" />
      <label for="font-weight-normal">normal</label><br />
      <input
        type="radio"
        id="font-weight-bold"
        name="font_weight"
        value="700" />
      <label for="font-weight-bold">bold</label>
    </div>

    <div class="setPropCont">
      font-size<br />
      <input type="radio" id="font-size-12px" name="font_size" value="12px" />
      <label for="font-size-12px">12px</label><br />
      <input
        type="radio"
        id="font-size-16px"
        name="font_size"
        value="16px"
        checked />
      <label for="font-size-16px">16px</label><br />
      <input type="radio" id="font-size-24px" name="font_size" value="24px" />
      <label for="font-size-24px">24px</label>
    </div>

    <div class="setPropCont">
      line-height<br />
      <input
        type="radio"
        id="line-height-none"
        name="line_height"
        checked
        value="" />
      <label for="line-height-none">omit value</label><br />
      <input
        type="radio"
        id="line-height-1-2"
        name="line_height"
        value="/1.2" />
      <label for="line-height-1-2">1.2</label><br />
      <input type="radio" id="line-height-3" name="line_height" value="/3" />
      <label for="line-height-3">3</label>
    </div>
    <br />

    <div class="setPropCont fontfamily">
      font-family<br />
      <input
        type="radio"
        id="font-family-courier"
        name="font_family"
        checked
        value="courier" />
      <label for="font-family-courier">courier</label><br />
      <input
        type="radio"
        id="font-family-serif"
        name="font_family"
        value="serif" />
      <label for="font-family-serif">serif</label><br />
      <input
        type="radio"
        id="font-family-sans-serif"
        name="font_family"
        value="sans-serif" />
      <label for="font-family-sans-serif">sans-serif</label><br />
      <input
        type="radio"
        id="font-family-arial"
        name="font_family"
        value="arial" />
      <label for="font-family-arial">Arial</label><br />
      <input
        type="radio"
        id="font-family-monospace"
        name="font_family"
        value="monospace" />
      <label for="font-family-monospace">monospace</label><br />
      <input
        type="radio"
        id="font-family-cursive"
        name="font_family"
        value="cursive" />
      <label for="font-family-cursive">cursive</label><br />
      <input
        type="radio"
        id="font-family-fantasy"
        name="font_family"
        value="fantasy" />
      <label for="font-family-fantasy">fantasy</label><br />
      <input
        type="radio"
        id="font-family-system-ui"
        name="font_family"
        value="system-ui" />
      <label for="font-family-system-ui">system-ui</label><br />
    </div>
  </div>

  <div class="cf propInputs">
    <div class="propInputCont tar">font :</div>
    <div class="propInputCont">
      <input type="text" class="curCss" id="input_font_style" /><br />
      font-style <br />
      optional
    </div>
    <div class="propInputCont">
      <input type="text" class="curCss" id="input_font_variant" /> <br />
      font-variant <br />
      optional
    </div>
    <div class="propInputCont">
      <input type="text" class="curCss" id="input_font_weight" /> <br />
      font-weight <br />
      optional
    </div>
    <div class="propInputCont">
      <input type="text" class="curCss mandatory" id="input_font_size" /> <br />
      font-size <br />
      mandatory
    </div>
    <div class="propInputCont">
      <input type="text" class="curCss" id="input_line_height" /> <br />
      line-height <br />
      optional
    </div>
    <div class="propInputCont">
      <input type="text" class="curCss mandatory" id="input_font_family" />
      <br />
      font-family <br />
      mandatory
    </div>
  </div>
</form>

<div class="fontShortHand">
  This is some sample text.<br />
  This is some more sample text.
</div>

body,
input {
  font: 14px "Arial";
  overflow: hidden;
}

.propInputCont {
  float: left;
  text-align: center;
  margin-right: 5px;
  width: 80px;
}

.setPropCont {
  float: left;
  margin-right: 5px;
  width: 120px;
}

.propInputs,
.setPropCont {
  margin-bottom: 1em;
}

.curCss {
  border: none;
  border-bottom: 1px solid black;
  text-align: center;
  width: 80px;
}

.mandatory {
  border-bottom-color: red;
}

.cf::before,
.cf::after {
  content: " ";
  display: table;
}

.cf::after {
  clear: both;
}

.tar {
  width: 40px;
  text-align: right;
}
.fontfamily {
  display: inline-block;
}

const textAreas = document.getElementsByClassName("curCss");

function getProperties() {
  return (
    `${getCheckedValue("font_style")} ` +
    `${getCheckedValue("font_variant")} ` +
    `${getCheckedValue("font_weight")} ` +
    `${getCheckedValue("font_size")}` +
    `${getCheckedValue("line_height")} ` +
    `${getCheckedValue("font_family")}`
  );
}

function getCheckedValue(radioName) {
  const radios = document.forms[0].elements[radioName];
  for (const radio of radios) {
    if (radio.checked) {
      const curElemName = `input_${radioName}`;
      const curElem = document.getElementById(curElemName);
      curElem.value = radio.value;

      return radio.value;
    }
  }
}

function setCss() {
  injectCss(getProperties());
}

function injectCss(cssFragment) {
  const old = document.body.getElementsByTagName("style");
  if (old.length > 1) {
    old[1].parentElement.removeChild(old[1]);
  }
  css = document.createElement("style");
  css.textContent = `.fontShortHand{font: ${cssFragment}}`;
  document.body.appendChild(css);
}

setCss();

document.querySelectorAll("input[type='radio']").forEach((el) => {
  el.addEventListener("change", setCss);
});