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CSS

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HTML 

              
                <h2>Tables</h2>

<!-- Start tables -->
<h3>Small</h3>
<table class="m-table m-table--responsive-small">
  <caption>This is a placeholder caption to show where it is displayed.</caption>
  <thead>
    <tr>
      <th>Header Title</th>
      <th>Header Title</th>
      <th>Header Title</th>
      <th>Header Title</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
  </tbody>
</table>

<h3>Medium</h3>
<table class="m-table m-table--responsive-medium">
  <caption>This is a placeholder caption to show where it is displayed.</caption>
  <thead>
    <tr>
      <th>Header Title</th>
      <th>Header Title</th>
      <th>Header Title</th>
      <th>Header Title</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
  </tbody>
</table>

<h3>Large</h3>
<table class="m-table m-table--responsive-large">
  <caption>This is a placeholder caption to show where it is displayed.</caption>
  <thead>
    <tr>
      <th>Header Title</th>
      <th>Header Title</th>
      <th>Header Title</th>
      <th>Header Title</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
    <tr>
      <th data-th="Header Title" scope="row">Cell content</th>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
      <td data-th="Header Title">Cell content</td>
    </tr>
  </tbody>
</table>
!

CSS 

              
                /* https://unpkg.com/@umich-lib/web@1/umich-lib.css */

table.m-table {
  border-collapse: collapse;
  border-spacing: 0;
  width: 100%;
}
.m-table caption,
.m-table th {
  text-align: left;
}
.m-table caption {
  color: var(--color-neutral-300);
}
.m-table tr > * {
  border-bottom: solid 1px var(--color-neutral-100);
  padding: var(--space-medium) 0;
  vertical-align: top;
}
.m-table tr > *:not(:last-child) {
  padding-right: var(--space-x-large);
}
.m-table th {
  font-size: var(--text-xxx-small);
  font-weight: var(--extrabold);
  letter-spacing: 1.25px;
  text-transform: uppercase;
  vertical-align: middle;
}
.m-table th:not([scope^='row']) {
  border-bottom: solid var(--space-xxx-small) var(--color-maize-400);
}
.m-table tr > *[data-th]:before {
  content: attr(data-th) ':\00a0';
  display: none;
}
.m-table tr > td[data-th]:before {
  font-weight: var(--semibold);
}
@media only screen and (max-width: 1200px) {
  .m-table--responsive-large thead {
    position: absolute !important;
    height: 1px;
    width: 1px;
    overflow: hidden;
    clip: rect(1px 1px 1px 1px);
    clip: rect(1px, 1px, 1px, 1px);
  }
  .m-table--responsive-large tr > * {
    display: block;
  }
  .m-table--responsive-large tr > *:not(:last-child) {
    border-bottom: 0;
    padding-bottom: 0;
    padding-right: 0;
  }
  .m-table--responsive-large tr > *[data-th]:not(th) + *[data-th] {
    padding-top: 0;
  }
  .m-table--responsive-large tr > *[data-th]:before {
    display: inline;
  }
}
@media only screen and (max-width: 920px) {
  .m-table--responsive-medium thead {
    position: absolute !important;
    height: 1px;
    width: 1px;
    overflow: hidden;
    clip: rect(1px 1px 1px 1px);
    clip: rect(1px, 1px, 1px, 1px);
  }
  .m-table--responsive-medium tr > * {
    display: block;
  }
  .m-table--responsive-medium tr > *:not(:last-child) {
    border-bottom: 0;
    padding-bottom: 0;
    padding-right: 0;
  }
  .m-table--responsive-medium tr > *[data-th]:not(th) + *[data-th] {
    padding-top: 0;
  }
  .m-table--responsive-medium tr > *[data-th]:before {
    display: inline;
  }
}
@media only screen and (max-width: 720px) {
  .m-table--responsive-small thead {
    position: absolute !important;
    height: 1px;
    width: 1px;
    overflow: hidden;
    clip: rect(1px 1px 1px 1px);
    clip: rect(1px, 1px, 1px, 1px);
  }
  .m-table--responsive-small tr > * {
    display: block;
  }
  .m-table--responsive-small tr > *:not(:last-child) {
    border-bottom: 0;
    padding-bottom: 0;
    padding-right: 0;
  }
  .m-table--responsive-small tr > *[data-th]:not(th) + *[data-th] {
    padding-top: 0;
  }
  .m-table--responsive-small tr > *[data-th]:before {
    display: inline;
  }
}
.m-table--responsive thead {
  position: absolute !important;
  height: 1px;
  width: 1px;
  overflow: hidden;
  clip: rect(1px 1px 1px 1px);
  /* IE6, IE7 */
  clip: rect(1px, 1px, 1px, 1px);
}
.m-table--responsive tr > * {
  display: block;
}
.m-table--responsive tr > *:not(:last-child) {
  border-bottom: 0;
  padding-bottom: 0;
  padding-right: 0;
}
.m-table--responsive tr > *[data-header]:not(th) + *[data-header] {
  padding-top: 0;
}
.m-table--responsive tr > *[data-header]:before {
  content: attr(data-header) ':\00a0';
}
.m-table--responsive tr > td[data-header]:before {
  font-weight: var(--semibold);
}
!

JS 

              
                /*
Automatically sets responsive state based on smallest-possible width. This will one day be replaced with @container, when widely available: https://caniuse.com/?search=%40container
*/

// Make sure everything is loaded before continuing
window.addEventListener('load', () => {
  // Responsive table class
  const responsiveClass = 'm-table--responsive';
  // Find and loop through each table
  const getTables = document.querySelectorAll('table.m-table');
  getTables.forEach((table) => {
    // Get parent element
    const parent = table.parentElement;
    // Get smallest possible width of table
    table.setAttribute('style', 'width: min-content;');
    const tableWidth = table.scrollWidth;
    table.removeAttribute('style');
    // Add responsive table class if table width is greater than parent width
    window.addEventListener('resize', (event) => {
      // Get left and right padding of parent
      let parentHorizontalPadding = 0;
      ['left', 'right'].forEach((side) => parentHorizontalPadding += parseInt(getComputedStyle(parent).getPropertyValue(`padding-${side}`)));
      // Get parent width, minus padding
      const parentWidth = parent.clientWidth - parentHorizontalPadding;
      // Compare widths and check if class exists
      if (tableWidth > parentWidth) {
        table.classList.add(responsiveClass);
      } else {
        table.classList.remove(responsiveClass);
      }
    });
  });
  // Trigger resize event
  window.dispatchEvent(new Event('resize'));
});
!
999px

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