JSFiddle - React, Tailwind, and code Playground

HTML

<div class="booking-time">
  <div class="inner">
    <button type="button" class="btn btn-flat">
      8:00 AM
    </button>
    <button type="button" class="btn btn-flat">
      8:15 AM
    </button>
    <button type="button" class="btn btn-flat">
      8:30 AM
    </button>
    <button type="button" class="btn btn-flat">
      8:45 AM
    </button>
    <button type="button" class="btn btn-flat">
      9:00 AM
    </button>
    <button type="button" class="btn btn-flat">
      9:15 AM
    </button>
    <button type="button" class="btn btn-flat">
      9:30 AM
    </button>
    <button type="button" class="btn btn-flat">
      9:45 AM
    </button>
    <button type="button" class="btn btn-flat">
      10:00 AM
    </button>
    <button type="button" class="btn btn-flat">
      10:15 AM
    </button>
    <button type="button" class="btn btn-flat">
      10:30 AM
    </button>
    <button type="button" class="btn btn-flat">
      10:45 AM
    </button>
    <button type="button" class="btn btn-flat">
      11:00 AM
    </button>
    <button type="button" class="btn btn-flat">
      11:15 AM
    </button>
    <button type="button" class="btn btn-flat">
      11:30 AM
    </button>
    <button type="button" class="btn btn-flat">
      11:45 AM
    </button>
  </div>
</div>

CSS

.booking-time{
  font-size: 0;
  line-height: 0;
  border: 1px solid red;
  padding: 5px;
  text-align: center;
}
.inner{
  display:block;
  max-width:90%;
  margin:0 auto;
  text-align: left;
}
.btn{
  width:100px;
  background: #3578d5;
  color: #fff;
  display: inline-block;
  vertical-align: middle;
  font-size: 14px;
  line-height: 20px;
  padding: 8px 16px;
  font-weight: 500;
  text-align: center;
  text-decoration: none;
  text-transform: uppercase;
  cursor: pointer;
  border: none;
  border-radius: 2px;
  overflow: hidden;
  position: relative;
  transition: box-shadow 0.3s, color 0.3s, background 0.3s;
  margin: 0 5px 5px 0;
}