无法将 CSS 列居中

Question

我在 css 中有一个三列框，我需要它在桌面的页面上居中，然后在 600 像素或更小的范围内将列堆叠在一起。除了以桌面视图为中心之外，我一切正常。

我尝试添加 justify-content: relative，添加包装器 align: center 和其他几行不起作用的代码。非常感谢任何帮助。

这是我目前拥有的代码：

* {
  box-sizing: border-box;
}


/* Create three equal columns that floats next to each other */

.column {
  float: left;
  width: 178px;
}


/* Clear floats after the columns */

.row:after {
  content: "";
  display: table;
  clear: both;
}


/* Responsive layout - makes the three columns stack on top of each other instead of next to each other */

@media screen and (max-width: 600px) {
  .column {
    width: 100%;
  }
}

<p align="center">
  <font size="5" color="336699"><strong>Great American Song Contest</strong></font>
</p>
<p align="center">
  <font size="3" color="a91e21"><strong>3 Easy Ways To Enter Your Songs</strong></font>
</p>

<div class="wrapper">
  <div class="row">
    <div class="column">

      <p>
        <a href="https://www.greatamericansong.com/newsite-backup/Form-Prepage.php/"><img src="https://www.greatamericansong.com/newsite-backup/images/submit-online.gif" alt="" width="178" height="158"></p>
    </div>
    <div class="column">

      <p>
        <a href="https://www.greatamericansong.com/newsite-backup/Entry-Direct.php/"><img src="https://www.greatamericansong.com/newsite-backup/images/submit-email.gif" alt="" width="178" height="158"></p>
    </div>
    <div class="column">

      <p>
        <a href="https://www.greatamericansong.com/newsite-backup/entry-mail.php/"><img src="https://www.greatamericansong.com/newsite-backup/images/submit-mail.gif" alt="" width="178" height="158"></a>
      </p>
    </div>
  </div>
</div>

<div align="center"> <img src="//shield.sitelock.com/shield/greatamericansong.com" id="sl_shield_image" style="cursor: pointer;" alt="SiteLock" align="middle" />
  <script id="sl_shield" type="text/javascript" src="//shield.sitelock.com/sitelock.js" language="javascript"></script>
</div>
<p align="center">


  <p></p>
  <p align="center"><strong>* WRITERS RETAIN ALL RIGHTS TO THEIR SONGS, LYRICS & COMPOSITIONS *</strong></p>

  <p>
    <font size="3" color="a91e21"><strong>2021 Rules & Entry:</strong></font>
  </p>

  <p>The Great American Song Contest is open to songwriters, lyricists & music composers worldwide.</p>

  <p align="center"><strong>* WRITERS RETAIN ALL RIGHTS TO THEIR SONGS, LYRICS & COMPOSITIONS *</strong></p>

Answer 1

将专用类应用于这些列的父级（在我的示例中：class="x"），在其上使用display: flex; 和justify-content: center，然后在媒体查询中将其更改为flex-direction: column（将它们放在下面彼此）和align-items: center;（使它们居中）。忘记花车......

* {
  box-sizing: border-box;
}
.column {
  width: 178px;
}

.x {
display: flex;
justify-content: center;
}

@media screen and (max-width: 600px) {
  .x {
    flex-direction: column;
    align-items: center;
  }
}

<p align="center">
  <font size="5" color="336699"><strong>Great American Song Contest</strong></font>
</p>
<p align="center">
  <font size="3" color="a91e21"><strong>3 Easy Ways To Enter Your Songs</strong></font>
</p>

<div class="wrapper">
  <div class="x">
    <div class="column">

      <p>
        <a href="https://www.greatamericansong.com/newsite-backup/Form-Prepage.php/"><img src="https://www.greatamericansong.com/newsite-backup/images/submit-online.gif" alt="" width="178" height="158"></p>
    </div>
    <div class="column">

      <p>
        <a href="https://www.greatamericansong.com/newsite-backup/Entry-Direct.php/"><img src="https://www.greatamericansong.com/newsite-backup/images/submit-email.gif" alt="" width="178" height="158"></p>
    </div>
    <div class="column">

      <p>
        <a href="https://www.greatamericansong.com/newsite-backup/entry-mail.php/"><img src="https://www.greatamericansong.com/newsite-backup/images/submit-mail.gif" alt="" width="178" height="158"></a>
      </p>
    </div>
  </div>
</div>

<div align="center"> <img src="//shield.sitelock.com/shield/greatamericansong.com" id="sl_shield_image" style="cursor: pointer;" alt="SiteLock" align="middle" />
  <script id="sl_shield" type="text/javascript" src="//shield.sitelock.com/sitelock.js" language="javascript"></script>
</div>
<p align="center">


  <p></p>
  <p align="center"><strong>* WRITERS RETAIN ALL RIGHTS TO THEIR SONGS, LYRICS & COMPOSITIONS *</strong></p>

  <p>
    <font size="3" color="a91e21"><strong>2021 Rules & Entry:</strong></font>
  </p>

  <p>The Great American Song Contest is open to songwriters, lyricists & music composers worldwide.</p>

  <p align="center"><strong>* WRITERS RETAIN ALL RIGHTS TO THEIR SONGS, LYRICS & COMPOSITIONS *</strong></p>