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CSS

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HTML 

              
                <div class="l-grid l-grid--half-half l-grid--gutter-large l-full-height">
     <div class="l-grid__item l-grid theme-green l-center-center ms-center-content">
          <div class="content first ms-align-center">
          <h2 class="heading">Down the Rabbit Hole</h2>
          <p class="description">Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do: once or twice she had peeped into the book her sister was reading, but it had no pictures or conversations in it, "and what is the use of a book," thought Alice, "without pictures or conversation?"</p>
          </div>
     </div>
     <div class="l-grid__item l-grid l-center-center theme-white second ms-center-content">
          <div class="content ms-align-center">
          <h2 class="heading">Advice from a Caterpillar</h2>
          <p class="description">The Caterpillar and Alice looked at each other for some time in silence: at last the Caterpillar took the hookah out of its mouth, and addressed her in a languid, sleepy voice.
“Who are you?” said the Caterpillar.
This was not an encouraging opening for a conversation. Alice replied, rather shyly, “I—I hardly know, Sir, just at present—at least I know who I was when I got up this morning, but I think I must have been changed several times since then.” </p>
          
     </div>
</div>
!

CSS 

              
                .l-grid {
     display: -ms-grid;
}

* {
     box-sizing: border-box;
}

body {
   background: #111;
   padding: 1rem; 
}


.l-grid--half-half {
     -ms-grid-columns: 1fr 1rem 1fr;
     -ms-grid-rows: minmax(100vh, 1fr);
}

.second {
     -ms-grid-column: 3;
}

/* Aligning with legacy grid is a little more difficult
 because of the lack of align-items, you must use align-self */

.ms-center-content {
     -ms-grid-columns: 1fr;
     -ms-grid-rows: 1fr;
}

.ms-align-center {
     -ms-grid-column: 1;
     -ms-grid-column-align: center;
     -ms-grid-row-align: center;
}

/* Evergreen browsers that don't yet support grid */
@supports not(display: -ms-grid) {
     
     .l-grid {
          display: flex; 
     }

     .l-grid--half-half > .l-grid__item {
          flex: 1 1 auto;
     }

     .l-grid--gutter-large {
          margin-left: -1rem;
     }

     .l-grid--gutter-large > .l-grid__item {
          margin-left: 1rem;
     }
}

/* Evergreen browsers with full grid support */
@supports (display: grid) {
     /* Only the display: grid part needs a feature query */
     .l-grid {
          display: grid;
     } 
     
     /* Reset the margins since we no longer need them */
     .l-grid--gutter-large {
          margin: initial;
     }
     
     .l-grid--gutter-large > .l-grid__item {
          margin: initial;
     }
}

/* Declares two columns 1 fraction each */
.l-grid--half-half {
     grid-template-columns: 1fr 1fr;
}

/* Declares a gutter of 1rem between grid items */
.l-grid--gutter-large {
     grid-gap: 1rem;
}


.l-center-center {
     align-items: center;
     justify-content: center;
}

.l-full-height {
     min-height: 100vh;
}

.theme-green {
     background: #4dab6b;
     color: #fff;
}

.theme-white {
     background: #fff;
     color: #111;
}

.content {
     max-width: 300px;
}

.heading {
     font-family: 'Playfair Display', serif;
     font-weight: 700;
     font-size: 2.5rem;
     line-height: 1.2;
     margin-bottom: 1rem;

}

.description {
     font-family: 'Raleway', sans-serif;
     font-weight: 400;
     font-size: 0.9rem;
     line-height: 1.5;
}
!

JS
!
999px

Console