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HTML

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About the <head>

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div class="parent">
  <button class="action-btn">
    <selectedoption id="pull-request-btn"></selectedoption>
  </button>
  <select selectedoptionelement="pull-request-btn">
    <button class="open-list-btn">
      <span class="arrow">
        <figure>↓</figure> <!-- should be image, using this for demo shortcut only -->
      </span>
    </button>
    <option value="merge-commit">
      <span class="preview-heading">Create a merge commit</span>
      <span class="action-heading">Merge Pull Request</span>
      <span class="description">All commits from this branch will be added to the base branch via a merge commit.</span>
    </option>
    <option value="squash-merge">
      <span class="preview-heading">Squash and merge</span>
      <span class="action-heading">Squash and merge</span>
      <span class="description">The 1 commit from this branch will be added to the base branch.</span>
    </option>
    <option value="rebase-merge">
      <span class="preview-heading">Rebase and merge</span>
      <span class="action-heading">Rebase and merge</span>
      <span class="description">The 1 commit from this branch will be rebased and added to the base branch.</span>
    </option>
  </select>
</div>
!

CSS 

              
                select,
::picker(select) {
  appearance: base-select;
}

option,
button {
  font-family: system-ui;
  font-size: 1rem;
  padding: 1rem 1.5rem 1rem 2rem;
}

button {
  color: white;
  border: 1px solid #207a39;
  margin-bottom: 0.25rem;
  
  &:hover {
    background-color: #1a7f37;
    cursor: pointer;
  }
}

span {
  display: block;
  text-align: left;
}

.action-btn {
  background-color: #20883d;
  border-radius: 0.5rem 0 0 0.5rem;
  anchor-name: --pull-request-btn;
}

.open-list-btn {
  background-color: #1a7f37;
  border-radius: 0 0.5rem 0.5rem 0;
  
  &:hover,
  &:focus {
    background-color: #197935;
  }
}

::picker(select) {
  max-width: 350px;
  border-radius: 0.5rem;
  border: 1px solid lightgray;
  box-shadow: none;
  padding: 0;
  position-anchor: --pull-request-btn;
  position-area: bottom span-right;
}

option {
  white-space: unset; /* hmm.. why I need to do this? */
  line-height: 1.4;

  &:hover,
  &:focus {
    color: white;
    background-color: #0969da;
    cursor: pointer;
    & span {
      color: white;
    }
  }

  /*  Remove ::before checkmark spacing unless I want it there  */
  &::before {
    display: none;
  }
  
  &:checked::before {
    content: '✓';
    display: block;
    font-weight: 700;
    position: absolute;
    left: 0.75rem;
  }
}

.preview-heading,
.action-heading {
  font-weight: 600;
}

.description {
  font-size: 85%;
  color: gray;
}

option:not(:last-child) {
  border-bottom: 1px solid lightgray;
}

/* Swap headings */
option .action-heading {
  display: none;
}

selectedoption .description,
selectedoption .preview-heading {
  display: none;
}

.parent {
  display: grid;
  grid-template-columns: 220px auto;
}


body {
  padding: 2rem;
}
!

JS
!
999px

Console