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HTML

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Insecure Resource

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="post sidebar" data-direction="rtl">
  <div class="post__content flow prose">
    <p>
      Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec purus purus, accumsan nec sodales eget, lacinia at purus. Nunc vel ornare ante. Nunc ipsum lectus, mollis eu orci et, commodo posuere ante. Aliquam eget dui non orci gravida sagittis. Phasellus in diam enim. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Suspendisse fermentum justo ultrices vulputate dignissim. Pellentesque fringilla nisl est, volutpat dignissim leo vulputate in.
    </p>
    <p>
      Sed nec justo eu metus venenatis feugiat. Curabitur vel laoreet mi. Proin vel tellus nec purus congue malesuada. Vestibulum eros mauris, consequat ut fringilla in, tempor id metus. Aliquam feugiat vel magna pellentesque finibus. Donec at pretium sapien. Aenean sit amet tortor tempor libero convallis venenatis in a dolor. Praesent efficitur tristique tortor, at ullamcorper leo congue vel. Cras non efficitur eros. Vivamus scelerisque lorem lectus, vel suscipit libero accumsan eget. Morbi convallis bibendum vehicula.
    </p>
    <p>
      Duis luctus ligula id aliquet suscipit. Proin facilisis odio vestibulum, fermentum risus sed, gravida sapien. Nulla facilisi. Nullam luctus tellus at mi luctus vulputate sit amet eu velit. Mauris ac enim rhoncus libero elementum suscipit vel eu tortor. Fusce est risus, suscipit a urna ac, convallis convallis elit. Morbi vitae ipsum sit amet augue elementum ullamcorper. Duis vitae vulputate turpis. Suspendisse elementum tortor et elit condimentum malesuada. Pellentesque dapibus, dolor vehicula eleifend sollicitudin, erat quam pretium diam, in luctus velit mauris id est. Vestibulum facilisis purus dolor, eu sollicitudin ipsum malesuada et. In eros eros, suscipit ac tincidunt at, gravida vel dolor.
    </p>
    <div class="post__breakout">BREAKOUT</div>
    <p>
      Nullam quis augue eget ligula pretium venenatis. Curabitur sem magna, tempor a ultricies nec, porta eu est. Suspendisse aliquam posuere pharetra. Aliquam blandit nibh nibh, quis euismod lacus porta vel. Proin nulla nunc, pellentesque eget pulvinar non, dapibus eget nibh. Pellentesque dignissim vehicula nisi et faucibus. Sed pharetra, eros ut imperdiet congue, libero sapien tincidunt velit, ac aliquet est nulla in arcu. Sed ultrices viverra libero, blandit malesuada risus dictum ut. Sed nibh ligula, luctus id congue sed, tincidunt quis turpis.
    </p>
    <p>
      Curabitur molestie sodales metus quis finibus. Quisque id purus semper, porttitor lorem ac, consectetur lectus. Suspendisse auctor sem iaculis neque interdum, eget semper nulla ullamcorper. Ut consequat nunc ac gravida efficitur. Nam aliquam, sapien ac tempor cursus, ante urna accumsan quam, nec convallis magna est eget leo. Nunc vehicula velit eget est porta tincidunt. Aliquam nec mauris est. Aliquam tortor libero, tincidunt id posuere at, imperdiet non tortor. Pellentesque ultrices egestas elit vel placerat. Fusce lobortis dignissim nunc, aliquet blandit felis elementum a. Etiam non mattis justo. Nulla malesuada tortor non justo iaculis viverra.
    </p>
    <div class="post__break"></div>
  </div>
  <div class="post__sidebar">
    <div class="post__meta">META</div>
  </div>
</div>
!

CSS 

              
                .post {
  --sidebar-content-min-width: 60%;
  --sidebar-target-width: 15rem;
  --gutter: 3rem;

  position: relative;
  container-type: inline-size;
}

.post__breakout {
  background: red;
  width: 100cqi;
  position: relative;
  z-index: 1;
}

.post__meta {
  background: yellow;
  border-inline-start: 1px solid;
  height: 100%;
}

.post__sidebar {
  container-type: inline-size;
}

@container (width > 50vi) {
  .post__meta {
    border-inline-start: 0;
    border-block-start: 1px solid;
  }
}

/* 
SIDEBAR
More info: https://every-layout.dev/layouts/sidebar/
A layout that allows you to have a flexible main content area
and a "fixed" width sidebar that sits on the left or right.
If there is not enough viewport space to fit both the sidebar
width *and* the main content minimum width, they will stack
on top of each other

CUSTOM PROPERTIES AND CONFIGURATION
 --gutter (var(--space-size-1)): This defines the space
between the sidebar and main content.

--sidebar-target-width (20rem): How large the sidebar should be

--sidebar-content-min-width(50%): The minimum size of the main content area

EXCEPTIONS
.sidebar[data-direction='rtl']: flips the sidebar to be on the right 
*/
.sidebar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gutter, var(--space-s-l));
}

.sidebar:not([data-direction]) > :first-child {
  flex-basis: var(--sidebar-target-width, 20rem);
  flex-grow: 1;
}

.sidebar:not([data-direction]) > :last-child {
  flex-basis: 0;
  flex-grow: 999;
  min-width: var(--sidebar-content-min-width, 50%);
}

.sidebar[data-reversed] {
  flex-direction: row-reverse;
}

.sidebar[data-direction="rtl"] > :last-child {
  flex-basis: var(--sidebar-target-width, 20rem);
  flex-grow: 1;
}

.sidebar[data-direction="rtl"] > :first-child {
  flex-basis: 0;
  flex-grow: 999;
  min-width: var(--sidebar-content-min-width, 50%);
}
!

JS
!
999px

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