javascript - 将此多级 Bootstrap 4 下拉克隆克隆到 mimc btn-dark 样式时遇到问题

Question

我似乎无法弄清楚如何获得这个多级 bootstrap 4 克隆下拉菜单来模仿 bootstrap 4 btn-dark 的外观。链接和下拉菜单着色全部关闭，悬停着色，我不确定我应该调整哪些元素以匹配外观。任何帮助都会很棒 :)。

/* start multi level bootstrap style dropdown menu */
.dropdown-submenu {
    position: relative;
}

.dropdown-submenu>.dropdown-menu {
    top: 0;
    left: 100%;
    margin-top: -6px;
    margin-left: -1px;
    -webkit-border-radius: 0 6px 6px 6px;
    -moz-border-radius: 0 6px 6px;
    border-radius: 0 6px 6px 6px;
}

.dropdown-submenu:hover>.dropdown-menu {
    display: block;
}

.dropdown-submenu>a:after {
    display: block;
    content: " ";
    float: right;
    width: 0;
    height: 0;
    border-color: transparent;
    border-style: solid;
    border-width: 5px 0 5px 5px;
    border-left-color: #ccc;
    margin-top: 5px;
    margin-right: -10px;
}

.dropdown-submenu:hover>li{
	background-color: aqua;
}

.dropdown-submenu:hover>a:after {
    border-left-color: #fff;
}

.dropdown-submenu.pull-left {
    float: none;
}

.dropdown-submenu.pull-left>.dropdown-menu {
    left: -100%;
    margin-left: 10px;
    -webkit-border-radius: 6px 0 6px 6px;
    -moz-border-radius: 6px 0 6px 6px;
    border-radius: 6px 0 6px 6px;
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>



<div class="dropdown">
            <button class="btn btn-secondary dropdown-toggle btn-dark" type="button" id="dropdownMenu1" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              Dropdown
            </button>
            <ul class="dropdown-menu multi-level" role="menu" aria-labelledby="dropdownMenu">
                <li class="dropdown-item"><a href="#">Some action</a></li>
                <li class="dropdown-item"><a href="#">Some other action</a></li>
                <li class="dropdown-divider"></li>
                <li class="dropdown-submenu">
                  <a  class="dropdown-item" tabindex="-1" href="#">Hover me for more options</a>
                  <ul class="dropdown-menu">
                    <li class="dropdown-item"><a tabindex="-1" href="#">Second level</a></li>
                    <li class="dropdown-submenu">
                      <a class="dropdown-item" href="#">Even More..</a>
                      <ul class="dropdown-menu">
                          <li class="dropdown-item"><a href="#">3rd level</a></li>
                            <li class="dropdown-submenu"><a class="dropdown-item" href="#">another level</a>
                            <ul class="dropdown-menu">
                                <li class="dropdown-item"><a href="#">4th level</a></li>
                                <li class="dropdown-item"><a href="#">4th level</a></li>
                                <li class="dropdown-item"><a href="#">4th level</a></li>
                            </ul>
                          </li>
                            <li class="dropdown-item"><a href="#">3rd level</a></li>
                      </ul>
                    </li>
                    <li class="dropdown-item"><a href="#">Second level</a></li>
                    <li class="dropdown-item"><a href="#">Second level</a></li>
                  </ul>
                </li>
              </ul>
        </div>

Answer 1

编辑固定

使用“ul.dropdown-menu.multi-level.show”创建 CSS 声明以更改背景颜色。它被添加到代码片段以将其更改为#343a40。 :)

只是供将来引用的提示，使用 chrome，您可以按 F12 并打开检查器。检查要更改的元素并查看它的声明是什么。

然后使用“ul.dropdown-menu”创建一个声明来处理较低的分支。

ul.dropdown-menu.multi-level.show a:link{
color:white;
}
li.dropdown-item:focus, li.dropdown-item:hover {
background-color:#1d2124;
}
a.dropdown-item:hover {
background-color:#1d2124;
}
ul.dropdown-menu.multi-level.show {
background-color:#343a40;
}    
ul.dropdown-menu {
background-color:#343a40;
}

/* start multi level bootstrap style dropdown menu */
.dropdown-submenu {
    position: relative;
}
ul.dropdown-menu.multi-level.show a:link{
color:white;
}
li.dropdown-item:focus, li.dropdown-item:hover {
background-color:#1d2124;
}
a.dropdown-item:hover {
background-color:#1d2124;
}
ul.dropdown-menu.multi-level.show {
background-color:#343a40;
}    
ul.dropdown-menu {
background-color:#343a40;
}
.dropdown-submenu>.dropdown-menu {
    top: 0;
    left: 100%;
    margin-top: -6px;
    margin-left: -1px;
    -webkit-border-radius: 0 6px 6px 6px;
    -moz-border-radius: 0 6px 6px;
    border-radius: 0 6px 6px 6px;
}

.dropdown-submenu:hover>.dropdown-menu {
    display: block;
}

.dropdown-submenu>a:after {
    display: block;
    content: " ";
    float: right;
    width: 0;
    height: 0;
    border-color: transparent;
    border-style: solid;
    border-width: 5px 0 5px 5px;
    border-left-color: #ccc;
    margin-top: 5px;
    margin-right: -10px;
}

.dropdown-submenu:hover>li{
	background-color: aqua;
}

.dropdown-submenu:hover>a:after {
    border-left-color: #fff;
}

.dropdown-submenu.pull-left {
    float: none;
}

.dropdown-submenu.pull-left>.dropdown-menu {
    left: -100%;
    margin-left: 10px;
    -webkit-border-radius: 6px 0 6px 6px;
    -moz-border-radius: 6px 0 6px 6px;
    border-radius: 6px 0 6px 6px;
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>



<div class="dropdown">
            <button class="btn btn-secondary dropdown-toggle btn-dark" type="button" id="dropdownMenu1" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              Dropdown
            </button>
            <ul class="dropdown-menu multi-level" role="menu" aria-labelledby="dropdownMenu">
                <li class="dropdown-item"><a href="#">Some action</a></li>
                <li class="dropdown-item"><a href="#">Some other action</a></li>
                <li class="dropdown-divider"></li>
                <li class="dropdown-submenu">
                  <a  class="dropdown-item" tabindex="-1" href="#">Hover me for more options</a>
                  <ul class="dropdown-menu">
                    <li class="dropdown-item"><a tabindex="-1" href="#">Second level</a></li>
                    <li class="dropdown-submenu">
                      <a class="dropdown-item" href="#">Even More..</a>
                      <ul class="dropdown-menu">
                          <li class="dropdown-item"><a href="#">3rd level</a></li>
                            <li class="dropdown-submenu"><a class="dropdown-item" href="#">another level</a>
                            <ul class="dropdown-menu">
                                <li class="dropdown-item"><a href="#">4th level</a></li>
                                <li class="dropdown-item"><a href="#">4th level</a></li>
                                <li class="dropdown-item"><a href="#">4th level</a></li>
                            </ul>
                          </li>
                            <li class="dropdown-item"><a href="#">3rd level</a></li>
                      </ul>
                    </li>
                    <li class="dropdown-item"><a href="#">Second level</a></li>
                    <li class="dropdown-item"><a href="#">Second level</a></li>
                  </ul>
                </li>
              </ul>
        </div>