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                <div class="clamp-container">
  <h1 data-dynamic-font-size>Pithy Phrase</h1>
<div class="clamp-container">
  <h1 data-dynamic-font-size>Short but not too short</h1>
<div class="clamp-container">
  <h1 data-dynamic-font-size>Something with more substance</h1>
<div class="clamp-container">
  <h1 data-dynamic-font-size>Something with more substance and pizazz</h1>
<div class="clamp-container">
  <h1 data-dynamic-font-size>
    A longer but equally compelling headline that fills up a couple lines


                .clamp-container {
  background: aliceblue;
  border-radius: 4px;
  color: navy;
  font-family: sans-serif;
  margin-bottom: 1rem;
  max-width: 60rem;
  padding: 0.5rem 1rem;
  & h1 {
    display: block;
    font-size: 2rem;
    max-width: 40ch;
    text-wrap: balance;


                const dynamicFontSize = (textLength) => {
     * Edit these values to suit your needs
    // Them minimum and maximum font sizes in pixels
    const minFontSize = 32;
    const maxFontSize = 64;

    // The minimum and maximum line lengths in characters that should affect size
    const minLineLength = 12;
    const maxLineLength = 50;

    // The minimum and maximum viewport widths in pixels where resizing should occur
    const minViewportWidth = 480;
    const maxViewportWidth = 1400;

     * Danger, calculations below, tread carefully
    // Relative max font size, gets bigger the fewer characters there are, down to minLineLength
    const relativeMaxFontSize =
      textLength < minLineLength
        ? maxFontSize
        : textLength > maxLineLength
        ? minFontSize
        : maxFontSize -
          ((maxFontSize - minFontSize) * (textLength - minLineLength)) /
            (maxLineLength - minLineLength);

    // Relative max viewport width, gets smaller the bigger the font size so it doesn't resize too soon
    const relativeMaxViewportWidth =
      maxViewportWidth * (minFontSize / relativeMaxFontSize);

    // Relative min viewport width, gets bigger the smaller the font size so it doesn't resize too late
    const relativeMinViewportWidth =
      minViewportWidth * (maxFontSize / relativeMaxFontSize);

    // Viewport width calculations
    const viewportWidth =
      (100 * (maxFontSize - minFontSize)) /
      (relativeMaxViewportWidth - relativeMinViewportWidth);

    // Relative font size calculation
    const relativeFontSize =
      (relativeMinViewportWidth * maxFontSize -
        relativeMaxViewportWidth * minFontSize) /
      (relativeMinViewportWidth - relativeMaxViewportWidth);

    // The magic clamp
    return `clamp(${minFontSize / 16}rem, ${viewportWidth}vw + ${
      relativeFontSize / 16
    }rem, ${relativeMaxFontSize / 16}rem)`;

  const dynamicFontEls = document.querySelectorAll("[data-dynamic-font-size]");

  dynamicFontEls.forEach((dynamicFontEl) => { = dynamicFontSize(
      dynamicFontEl.textContent.replace(/(<([^>]+)>)/gi, "").trim().length