untitled fiddle

untitled

HTML

<div class="calendar-container">
  <div class="fieldsContainer">
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
    <div class="cube-lived"></div>
   ...

CSS

.calendar-container{
   background-color:rgb(151,203,228);
    height:100vh;
    overflow: scroll;
    overflow-x: hidden;
    display:flex;
    justify-content: center;
}

.fieldsContainer{
   width:90%;   
}

.cube-lived{
    float: left;
    width: 19px;
    height: 19px;
    border: 1px solid rgba(0, 0, 0, .2);
    margin: 1px;
    background-color: rgba(6,30,57);
  }