html – 将箭头选择器添加到按钮的中心

我试图通过CSS添加一个白色箭头到链接按钮的底部.但是,我无法统一所有按钮的箭头中心..

JSFIDDLE

HTML：

<div class="help-buttons">
    <a href="#" class="help-button">User information</a>
    <a href="#" class="help-button">Company information</a>
    <a href="#" class="help-button">Driver information</a>
</div>

CSS：

.help-buttons {
  margin: 75px auto;
  text-align: center;
}
.help-button {
  background: #1795db;
  color: #fff;
  padding: 15px 20px;
  font-family: 'Open sans';
  Box-shadow: 3px 3px 0px 0px rgba(0,0.2);
  margin: 0 30px;
}
.help-button:after {
  content: "";
  position: absolute;
  margin-top: 25px;
  margin-left: -75px;
  width: 0;
  height: 0;
  border-left: 13px solid transparent;
  border-right: 13px solid transparent;
  border-bottom: 13px solid #ffffff;
}

解决方法

> Make .help-button position：relative;这样箭头就相对于按钮定位了.
>负边距：之后应与边框大小相同.
>调整底部：-6px以获得您想要的尺寸.

Have a fiddle!

HTML

<div class="help-buttons">
        <a href="#" class="help-button">User information</a>
        <a href="#" class="help-button">Company information</a>
        <a href="#" class="help-button">Driver information</a>
    </div>

CSS

.help-buttons {
    margin: 75px auto;
    text-align: center;
}
.help-button {
    background: #1795db;
    color: #fff;
    padding: 15px 20px;
    font-family: 'Open sans';
    Box-shadow: 3px 3px 0px 0px rgba(0,0.2);
    margin: 0 30px;
    position: relative;
}
.help-button:after {
    content: "";
    position: absolute;
    left: 50%;
    bottom: -6px;
    margin-left: -13px;
    width: 0;
    height: 0;
    border-left: 13px solid transparent;
    border-right: 13px solid transparent;
    border-bottom: 13px solid #ffffff;
}