new-fiddle

by KaranR1999

HTML

<div class="main-container">
        <div class="container">
            <div class="boxes">s</div>
            <div class="boxes"></div>
            <div class="boxes"></div><br>
            <div class="boxes"></div>
            <div class="boxes"></div>
            <div class="boxes"></div><br>
            <div class="boxes"></div>
            <div class="boxes"></div>
            <div class="boxes"></div>
        </div>
    </div>

CSS

* {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

.main-container {
  width: 100%;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.boxes {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100px;
  height: 100px;
  border: 2px solid black;
  margin: 4px;
  font-size: 3em;
}