javascript - 如何在 CSS 中将 Accordion 居中对齐？

Question

我网页的左侧容器上有一个 Accordion ，默认情况下是左对齐的。我正在使用 CSS 将其居中对齐。我试过在 CSS 代码中使用 position: center, align: left 和 margin-left: 5px 但这些都不起作用。谁能帮我吗。提前致谢。

这是我的 CSS 代码:

    var acc_leftpanel = document.getElementsByClassName("accordion_leftpanel");
    var i;

    for (i = 0; i < acc_leftpanel.length; i++) {
      acc_leftpanel[i].onclick = function() {
        this.classList.toggle("active");
        var panel = this.nextElementSibling;
        if (panel.style.maxHeight) {
          panel.style.maxHeight = null;
        } else {
          panel.style.maxHeight = panel.scrollHeight + 'px';
        }
      }
    }

button.accordion_leftpanel {
  background-color: #2da0d9;
  color: #444;
  cursor: pointer;
  padding: 5px;
  width: 60%;
  border: none;
  align: center;
  text-align: center;
  outline: none;
  font-size: 12px;
  transition: 0.4s;
  border-radius: 25px;
}
button.accordion_leftpanel.active,
button.accordion_leftpanel:hover {
  background-color: #5ebb61;
}
button.accordion_leftpanel:after {
  color: #ffffff;
  font-weight: bold;
  float: center;
  margin-left: 8px;
}

<div class="leftcontentborder">
  <p align="center">LIST OF SOLVED PAPERS</p>
  <button class="accordion_leftpanel" align="center">June 2014</button>

  <div class="panel">
    <p>Paper 2</p>
    <p>Paper 3</p>
  </div>
</div>

Answer 1

使用边距居中，margin: 0 auto;

另外，查看 https://developer.mozilla.org/en-US/docs/Web/CSS