Question

我正在尝试通过CSS将白色箭头添加到链接按钮的底部。但是，我无法统一所有按钮的箭头中心..

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(0,0,0,0.2);
  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;
}

Answer 1

制作.help-button position: relative;，以便箭头相对于按钮定位。
:after上的负边距应与边框的尺寸相同。
调整bottom: -6px以获得所需的尺寸。

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(0,0,0,0.2);
    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;
}

Answer 2

这就是你追求的吗？ http://jsfiddle.net/6ysbwrx8/4/

诀窍在于将left位置设为50%，将margin-left设为负值，将箭头的宽度减半（以补偿“过冲”＃39;）。另请注意，我添加了position: rekative;以使绝对定位正常工作。

这是完整的CSS：

.help-button {
    background: #1795db;
    color: #fff;
    padding: 15px 20px;
    font-family: 'Open sans';
    box-shadow: 3px 3px 0px 0px rgba(0,0,0,0.2);
    margin: 0 30px;
    position: relative;
    white-space: no-wrap;
}
.help-button:after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    margin-left: -13px;
    margin-bottom: -3px;
    width: 0;
    height: 0;
    border-left: 13px solid transparent;
    border-right: 13px solid transparent;
    border-bottom: 13px solid #ffffff;
}

（我还添加了white-space: no-wrap;以防止您的按钮分成多行）

将箭头选择器添加到按钮的中心

2 个答案: