1.纯三角形的写法：
html:
<div class="tooltip-popper is-dark">消息提醒
<div class="popper-arrow"></div>
</div>
样式：
.tooltip-popper{
position: absolute;
border-radius: 4px;
padding: 10px;
font-size: 12px;
text-align: center;
white-space: nowrap;
line-height: 1.2;
min-width: 10px;
word-wrap: break-word;
transform-origin: left center;
z-index: 2007;
visibility: hidden;
opacity: 0;
top: 55px;
left: 50%;
transform: translateX(-50%);
transition: all .3s;
-webkit-transition: all .3s;
}
.tooltip-popper.is-dark{
background-color: #595959;
box-shadow: 0 12px 32px 0 rgba(38, 38, 38, 0.16);
transition: opacity 0.3s;
color: #FFF;
}
.tooltip-popper .popper-arrow,
.tooltip-popper .popper-arrow::after {
position: absolute;
display: block;
width: 0;
height: 0;
border-color: transparent;
border-style: solid;
}
.tooltip-popper .popper-arrow {
top: -9px;
width: 0;
height: 0;
left: 50%;
margin-left: -5px;
border-left: 6px solid transparent;
border-right: 6px solid transparent;
border-bottom: 6px solid #595959;
}
2.正方形的写法：
html:
<div class="popper-arrow"></div>
</div>
样式：
.tooltip-popper{
position: absolute;
border-radius: 4px;
padding: 10px;
font-size: 12px;
text-align: center;
white-space: nowrap;
line-height: 1.2;
min-width: 10px;
word-wrap: break-word;
transform-origin: left center;
z-index: 2007;
visibility: hidden;
opacity: 0;
top: 55px;
left: 50%;
transform: translateX(-50%);
transition: all .3s;
-webkit-transition: all .3s;
}
.tooltip-popper.is-dark{
background: #303133;
transition: opacity 0.3s;
color: #FFF;
}
.tooltip-popper .popper-arrow,
.tooltip-popper .popper-arrow::after {
position: absolute;
display: block;
width: 0;
height: 0;
border-color: transparent;
border-style: solid;
}
.tooltip-popper .popper-arrow {
border-width: 5px;
top: -3px;
width: 5px;
height: 0;
background: #303133;
left: 50%;
margin-left: -5px;
transform: rotate(45deg);
}
