JSFiddle - React, Tailwind, and code Playground

HTML

<div class="money_boxesRow">
    <div class="panel-i">
        <div class="panel-i-label">
            One Off Charge                                    
        </div>
        <span>                        
            £ <span id="total_one_off_charge">0.00</span>
        </span>
    </div>
    <div class="panel-i">
        <div class="panel-i-label">
            Monthly Charge                                    
        </div>
        <span>                        
            £ <span id="total_monthly_charge">0.00</span>
        </span>
    </div>
    <div class="panel-i">
        <div class="panel-i-label">
            Monthly Charge Total                                    
        </div>
        <span>                        
            £ <span id="total_lease">0.00</span>
        </span>
    </div>
    <div class="panel-i so_hide_commissions" style="display: none;">
        <div class="panel-i-label">
            Commission Total                                    
        </div>
        <span>                        
            £ <span id="total_commission">0.00</span>
        </span>
    </div>
</div>

CSS

.money_boxesRow{
    display: -webkit-flex;
    display: -moz-flex;
    display: -ms-flexbox;
    display: flex; 
    -webkit-align-items: stretch;
    -moz-align-items: stretch;
    -ms-align-items: stretch;
    align-items: stretch;
}
.panel-i{
    position: relative;
    margin: 4px 0;
    border:1px solid ;
    text-align: right;    
    min-height: 76px;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
    padding: 8px 10px 0;
    -webkit-flex: 1 1 30%;
    -moz-flex: 1 1 30%;
    -ms-flex: 1 1 30%;
    flex: 1 1 30%;  /* flex-grow flex-shrink, flex-basis */
}
.panel-i-label{
    text-transform: uppercase;
    font-size: 1.4em;
}
.panel-i > span{    
    font-size: 3.2em;    
    display: block;
    font-family: 'PT sans narrow';
    font-weight: bold;
}
.panel-i:not(:first-child){
    border-left: 0;
}