<div class="box">
        <div class="first-item">
            <h1>1</h1>
        </div>
        <div class="second-item">
            <h1>2</h1>
        </div>
        <div class="third-item">
            <h1>3</h1>
    
        </div>
        <div class="fourth-item">
            <h1>4</h1>
        </div>
    </div>

.box{
  display:flex;
  border-style: solid;
  border-color:midnightblue ;
  border-width: 3px;
  height: 150px;
  align-items: center;
}

.first-item{
  border-style: solid;
  border-width:1.5px;
  margin: 3px;
  background-color: mediumseagreen; 
}
.second-item{
  border-style: solid;
  border-width:1.5px;
  margin: 3px;
  background-color: seagreen; 
}

.third-item{
  border-style: solid;
  border-width:1.5px;
  margin: 3px;
  background-color: forestgreen; 
}
  
.fourth-item{
  border-style: solid;
  border-width:1.5px;
  margin: 3px;
  background-color: green; 
}