JSFiddle - React, Tailwind, and code Playground

HTML

<div class="counter">
    <div><span>1</span></div>,<div><span>2</span></div>,<div><span>3</span></div>
</div>

CSS

.counter {
    font-family: sans-serif;
    font-size:20px;
}

.counter div {
    display:inline-block;
    vertical-align:bottom;
}

.counter div:before, .counter div:after {
    content:"";
    display:block;
    width:30px;
    height:20px;
    border-radius:3px 3px 0 0;
    background-color:#333;
    border: 1px solid #000;
    box-shadow: 0 0 2px #AAA inset;
}

.counter span {
    display:block;
    height:43px;
    width:32px;
    text-align:center;
    line-height:40px;
    margin-top:-22px;
    color:#FFF;
    font-size:24px;
    text-shadow: 0 0 5px #000;
}

.counter div:after {
    border-radius: 0 0 3px 3px;
    border-top:0;
    margin-top:-21px;
}