Bootstrap 4 horizontal scroller div

Question

I got this working for Bootstrap 3 but the same code won't work in Bootstrap 4.

Basically, I'm trying to create a horizontal scroll for DIV and here's a working JSFIDDLE for Bootstrap 3 (which I don't want): DEMO

The same code for Bootstrap 4 isn't working though! Here's the JSFiddle for Bootstrap 4: https://jsfiddle.net/6kvw2q5h/

HTML

<div class="live__scroll">
  <div class="row text-center">
    <div class="col-8 live__scroll--box">1</div>
    <div class="col-8 live__scroll--box">1</div>
    <div class="col-8 live__scroll--box">1</div>
    <div class="col-8 live__scroll--box">1</div>
    <div class="col-8 live__scroll--box">1</div>
    <div class="col-8 live__scroll--box">1</div>
    <div class="col-8 live__scroll--box">1</div>
    </div>
</div>

CSS

.live__scroll {
  overflow-x: auto;
  overflow-y: hidden;
  white-space: nowrap;
}
.live__scroll .live__scroll--box {
  display: inline-block;
  float: none;
  padding: 15px;
  border: 1px solid red;
}

What am I doing wrong? I'm at wits end.

Answer 1

HTML

<div class="container testimonial-group">
    <div class="row text-center flex-nowrap">
        <div class="col-sm-4">1</div>
        <div class="col-sm-4">2</div>
        <div class="col-sm-4">3</div>
        <div class="col-sm-4">4</div>
        <div class="col-sm-4">5</div>
        <div class="col-sm-4">6</div>
        <div class="col-sm-4">7</div>
        <div class="col-sm-4">8</div>
        <div class="col-sm-4">9</div>
    </div>
</div>

CSS

/* The heart of the matter */
.testimonial-group > .row {
  overflow-x: auto;
  white-space: nowrap;
}
.testimonial-group > .row > .col-sm-4 {
  display: inline-block;
  float: none;
}

/* Decorations */
.col-sm-4 { color: #fff; font-size: 48px; padding-bottom: 20px; padding-top: 18px; }
.col-sm-4:nth-child(3n+1) { background: #c69; }
.col-sm-4:nth-child(3n+2) { background: #9c6; }
.col-sm-4:nth-child(3n+3) { background: #69c; }

NOTE : codepen