<div class="grid">
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
</div>
* { 
   margin: 0;
}

.grid {
    display: grid;
    grid-gap: 1px;
    grid-template-columns: repeat(12, 1fr);
    grid-auto-rows: minmax(auto, auto);
    height: 100vh;
    margin-left: auto;
    margin-right: auto;
    
    background-color: black;
    
    &__item {
        grid-column: span 1;
        
        background-color: white;
    }
}
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