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Insecure Resource

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HTML 

              
                <ul class="c-accordion">
 <li id="joker" class="c-accordion__item" style="--cover: url(https://i.pinimg.com/originals/1f/62/51/1f6251d4e9ab99d8bd84a4548a6f902e.jpg)">
  <a href="#joker" class="c-accordion__action">
   <div class="c-accordion__content">
    <h2 class="c-accordion__title c-accordion__title--hero c-accordion__title--hover-show">Jocker</h2>
     <p class="c-accordion__description">In Gotham City, mentally troubled comedian Arthur Fleck is disregarded and mistreated by society. He then embarks on a downward spiral of revolution and bloody crime. This path brings him face-to-face with his alter-ego: the Joker.</p>
   </div>
   <div class="c-accordion__aside">
    <h2 class="c-accordion__title c-accordion__title--hover-hide">Jocker</h2>
   </div>
  </a>
 </li>
 <li id="john-wick" class="c-accordion__item" style="--cover: url(https://media1.fdncms.com/clevescene/imager/u/original/30502117/johnwick.jpg)">
  <a href="#john-wick" class="c-accordion__action">
   <div class="c-accordion__content">
    <h2 class="c-accordion__title c-accordion__title--hero c-accordion__title--hover-show">John Wick</h2>
    <p class="c-accordion__description">
     John Wick is on the run after killing a member of the international assassins' guild, and with a $14 million price tag on his head, he is the target of hit men and women everywhere.
    </p>
   </div>
   <div class="c-accordion__aside">
    <h2 class="c-accordion__title c-accordion__title--hover-hide">John Wick</h2>
   </div>
  </a>
 </li>
 <li id="black-panther" class="c-accordion__item" style="--cover: url(https://cdn.vox-cdn.com/uploads/chorus_image/image/66412368/BlackPanther596d2f1e1f199.0.jpg)">
  <a href="#black-panther" class="c-accordion__action">
   <div class="c-accordion__content">
    <h2 class="c-accordion__title c-accordion__title--hero c-accordion__title--hover-show">Black Panther</h2>
    <p class="c-accordion__description">
     T'Challa, heir to the hidden but advanced kingdom of Wakanda, must step forward to lead his people into a new future and must confront a challenger from his country's past.
    </p>
   </div>
   <div class="c-accordion__aside">
    <h2 class="c-accordion__title c-accordion__title--hover-hide">Black Panther</h2>
   </div>
  </a>
 </li>
 <li id="marvel-captain" class="c-accordion__item" style="--cover: url(https://www.hqzona.com.br/wp-content/uploads/2020/05/captain-marvel-ss-main.jpg)">
  <a href="#marvel-captain" class="c-accordion__action">
   <div class="c-accordion__content">
    <h2 class="c-accordion__title c-accordion__title--hero c-accordion__title--hover-show">Marvel Captain</h2>
    <p class="c-accordion__description">
     Carol Danvers becomes one of the universe's most powerful heroes when Earth is caught in the middle of a galactic war between two alien races.
    </p>
   </div>
   <div class="c-accordion__aside">
    <h2 class="c-accordion__title c-accordion__title--hover-hide">Marvel Captain</h2>
   </div>
  </a>
 </li>
</ul>
!

CSS 

              
                $component: '.c-accordion';

:root {
 font-family: 'Poppins', sans-serif;
 --color-primary: #3E66A0;
 
 
 --cover-placeholder: var(--color-primary);
}

body {
 padding: 0;
 margin: 0;
 height: 100vh;
}

#{$component} {
 list-style: none;
 padding: 0;
 margin: 0;
 height: 100%;
 display: flex;
 flex: 1 1 auto;
 overflow: hidden;
 &__item {
  --cover: var(--cover-placeholder);
  background: var(--cover);
  background-position: center center;
  background-size: cover;
  background-color: var(--cover-placeholder);
  background-blend-mode: luminosity;
  
  position: relative;
  flex-grow: 1;
  height: 100%;
  width: 100px;
  min-width: 2.05rem;
  transition: all .3s ease-in-out;
  
  &:hover, &:focus-within, &:target {
   _flex-grow: 2;
   width: 100%;
   background-color: transparent;
   #{$component} {
    &__title {
     &--hover-hide {
      max-height: 0;
      opacity: 0;
     }
     &--hover-show {
      opacity: 1;
     }
    }
    &__description {
     opacity: 1;
    }
   }
  }
  
  &:hover {
   cursor: pointer;
  }
 }
 &__action {
  position: absolute;
  display: flex;
  justify-content: center;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, .4);
  text-decoration: none;
 }
 &__title {
  color: white;
  margin: 0;
  max-height: 100%;
  transition: all .3s ease-in-out;
  overflow: hidden;
  &--hover-show {
   opacity: 0;
   width: 100%;
  }
  &--hero {
   font-size: 3rem;
   line-height: 150%;
  }
 }
 &__aside {
  padding: 1rem;
  position: absolute;
  height: 100%;
  right: 1rem;
  bottom: 0;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  display: flex;
  align-items: center;
  flex-wrap: nowrap;
  white-space: nowrap;
  &:before {
   content: '+';
   color: yellow;
   margin-bottom: 1rem;
   font-size: 2rem;
   display: inline-block;
  }
  &:after {
   content: '';
   flex-grow: 1;
   width: 1px;
   display: block;
   margin-top: 1rem;
   background-color: rgba(255, 255, 255, .2);
  }
 }
 &__content {
  padding: 2rem 2.5rem 0 2rem;
  width: 50%;
 }
 &__description {
  color: white;
  font-weight: 400;
  line-height: 120%;
  overflow-y: auto;
  overflow-x: hidden;
  height: 100%;
  opacity: 0;
  transition: all .3s ease-in-out;
 }
}
!

JS 

              
                /*
 ** Inspiration/Based: https://dribbble.com/shots/6584063-Daily-UI-Accordion-Cards-Experiment
 */
!
999px

Console