鼠标事件实现提示信息显隐

1.Tooltips：HTML

<span class="tooltip-toggle" data-tooltip="Sample text for your tooltip!">
Label for your tooltip
</span>

CSS

.tooltip-toggle {
cursor: pointer;
position: relative;
}
.tooltip-toggle::before {
top: -80px;
left: -80px;
background-color: #2B222A;
border-radius: 5px;
color: #fff;
content: attr(data-tooltip);
padding: 1rem;
text-transform: none;
-webkit-transition: all 0.5s ease;
transition: all 0.5s ease;
width: 160px;
}
.tooltip-toggle::after {

content: " ";

top: -12px; left: 9px; border-left: 5px solid transparent; border-right: 5px solid transparent; border-top: 5px solid #2B222A; width: 0;}.tooltip-toggle::before, .tooltip-toggle::after {

position: absolute;
color: #efefef;
font-family: monospace;  //字体等宽大小
font-size: 16px;
opacity: 0;
pointer-events: none;   //鼠标移不上去元素，只能通过鼠标事件将在捕获或冒泡阶触发父元素的事件侦听器。
text-align: center;
}
.tooltip-toggle:hover::before, .tooltip-toggle:hover::after {
opacity: 1;
-webkit-transition: all 0.75s ease;
transition: all 0.75s ease;
}

2.下拉菜单：

HTML

<div class="nav-container"><ul class="nav-items"><!-- Navigation --><li class="nav-item"><a href="#">Home</a></li><li class="nav-item"><a href="#">About</a></li><li class="nav-item"><a href="#">Contact</a></li><!-- Dropdown menu --><li class="nav-item nav-item-dropdown"><a class="dropdown-trigger" href="#">Settings</a><ul class="dropdown-menu"><li class="dropdown-menu-item"><a href="#">Dropdown Item 1</a></li><li class="dropdown-menu-item"><a href="#">Dropdown Item 2</a></li><li class="dropdown-menu-item"><a href="#">Dropdown Item 3</a></li></ul></li></ul></div>

CSSul,li{list-style: none;-webkit-padding-start: 0;}.nav-container { background-color: #fff; border-radius: 4px; box-shadow: 0px 0px 2px 0 rgba(153, 153, 153, 0.35); display: block; padding: 10px; max-width: 400px; margin: 0 auto; text-align: center;}a {text-decoration: none;color: #ED3E44;}.nav-item {padding: 1em;display: inline;}.nav-item-dropdown,.dropdown-trigger {  position: relative;}.nav-item-dropdown:hover > .dropdown-menu { display: block; opacity: 1;}.dropdown-trigger::after { content: "›"; position: absolute; color: #ED3E44; font-size: 24px; font-weight: bold; -webkit-transform: rotate(90deg); transform: rotate(90deg); top: -5px; right: -15px;}.dropdown-menu { background-color: #ED3E44; text-align: right; position: absolute; top: 2.5rem; right: -10px; display: none; opacity: 0; -webkit-transition: opacity 0.5s ease; transition: opacity 0.5s ease; width: 160px;}.dropdown-menu a { color: #fff;}.dropdown-menu-item { cursor: pointer; padding: 1em; text-align: center;}.dropdown-menu-item:hover { background-color: #eb272d;}.dropdown-trigger:focus + .dropdown-menu,.dropdown-trigger:hover + .dropdown-menu {display: block;opacity: 1; } .dropdown-menu-item { cursor: pointer; padding: 1em; text-align: center;  }.dropdown-menu-item:hover {background-color: darken(#ED3E44, 5%); }