html - 在 Bootstrap 4 中使 3 列宽度为 75% 并居中对齐

Question

我有以下 bootply 片段:https://www.bootply.com/FHwoiollCJ

如您所见，我有一个占宽度 75% 的元素。

我想将此框下方的 3 个元素居中对齐，以便第一个和第三个框不会悬垂。我该怎么做？

<header class="masthead text-white">
  <div class="overlay"></div>
  <div class="container">
    <div class="row">
      <div class="col-lg-9 mx-auto" style="background:rgba(0,0,0,0.3);">
        <h1 class="mb-5">H1</h1>
        <p>We pride ourselves...</p>
      </div>
    </div>
    <div class="row">
      <div class="col-lg-3 mx-auto">
          <div class="" style="background:red">
            <h3>TEST</h3>
            <p>test</p>
        </div>
      </div>
      <div class="col-lg-3 mx-auto">
        <div class="features-icons-item mx-auto mb-5 mb-lg-0 mb-lg-3" style="background:red">
          <h3>TEST</h3>
          <p>test</p>
        </div>
      </div>
      <div class="col-lg-3 mx-auto">
        <div class="features-icons-item mx-auto mb-0 mb-lg-3" style="background:red">
            <h3>TEST</h3>
            <p>test</p>
          </div>
        </div>
      </div>
      </div>
    </header>

Answer 1

试试这个:

    <div class="overlay"></div>
<div class="container">
  <div class="row">
    <div class="col-lg-9 mx-auto" style="background:rgba(0,0,0,0.3);">
      <h1 class="mb-5">H1</h1>
      <p>We pride ourselves...</p>
    </div>
  </div>
  <div class="row">
    <div class="col-lg-9 mx-auto" style="padding-left: 0;padding-right: 0;">
    <div class="row">
      <div class="col-lg-4 mx-auto">
        <div class="" style="background:red">
          <h3>TEST</h3>
          <p>test</p>
        </div>
      </div>
      <div class="col-lg-4 mx-auto">
        <div class="features-icons-item mx-auto mb-5 mb-lg-0 mb-lg-3" style="background:red">
          <h3>TEST</h3>
          <p>test</p>
        </div>
      </div>
      <div class="col-lg-4 mx-auto">
        <div class="features-icons-item mx-auto mb-0 mb-lg-3" style="background:red">
          <h3>TEST</h3>
          <p>test</p>
        </div>
      </div>
    </div>
  </div>
  </div>
</div>