我正在尝试在Bootstrap 5折叠时更改它的accordion's "accordion-button"颜色。

我在下面试过了。它会更改背景，但不会更改按钮的图标颜色。

.accordion-button.collapsed {
    color: white;
    background: blue;
}

如何更改Bootstrap 5的手风琴向下(折叠)图标？

推荐答案

因为它是在::after伪元素中设置的background-image(使用bootstrap icons)，所以更改图像

更新-(基于OP评论)

它用图像替换图标。如何更改现有图像(图标)的颜色？

因此使用相同的背景图像并将填充更改为#fff

请注意，SVG URL由引导程序编码

.accordion-button.collapsed {
  background: blue
}

.accordion-button.collapsed::after {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%23fff'%3e%3cpath fill-rule='evenodd' d='M1.646 4.646a.5.5 0 0 1 .708 0L8 10.293l5.646-5.647a.5.5 0 0 1 .708.708l-6 6a.5.5 0 0 1-.708 0l-6-6a.5.5 0 0 1 0-.708z'/%3e%3c/svg%3e");
}

<!-- CSS only -->
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.0-beta2/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-BmbxuPwQa2lc/FVzBcNJ7UAyJxM6wuqIj61tLrc4wSX0szH/Ev+nYRRuWlolflfl" crossorigin="anonymous">
<div class="accordion" id="accordionExample">
  <div class="accordion-item">
    <h2 class="accordion-header" id="headingOne">
      <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseOne" aria-expanded="true" aria-controls="collapseOne">
        Accordion Item #1
      </button>
    </h2>
    <div id="collapseOne" class="accordion-collapse collapse show" aria-labelledby="headingOne" data-bs-parent="#accordionExample">
      <div class="accordion-body">
        <strong>This is the first item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and
        hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="headingTwo">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo">
        Accordion Item #2
      </button>
    </h2>
    <div id="collapseTwo" class="accordion-collapse collapse" aria-labelledby="headingTwo" data-bs-parent="#accordionExample">
      <div class="accordion-body">
        <strong>This is the second item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing
        and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="headingThree">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseThree" aria-expanded="false" aria-controls="collapseThree">
        Accordion Item #3
      </button>
    </h2>
    <div id="collapseThree" class="accordion-collapse collapse" aria-labelledby="headingThree" data-bs-parent="#accordionExample">
      <div class="accordion-body">
        <strong>This is the third item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and
        hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
</div>