Div 未与顶部对齐

Question

为什么会这样？我需要有人能解释为什么 div 没有正确对齐？

HTML 和 CSS:

.horizontal-ruler {
  width: 100%;
  height: 25px;
  line-height: 25px;
  display: block;
  font-size: 14px;
  color: #373737;
}
.horizontal-ruler .ruler-unit {
  width: 30px;
  text-align: center;
  display: inline-block;
  line-height: 25px;
  height: 25px;
  vertical-align: middle;
}
.h-ruler-first-line,
.h-ruler-second-line {
  width: calc(50% - 15px);
  margin: 12px 0;
  height: 1px;
  background-color: #373737;
  display: inline-block;
}

<div class="horizontal-ruler">
  <div class="h-ruler-first-line"></div><!--
--><div class="ruler-unit">24"</div><!--
--><div class="h-ruler-second-line"></div>
</div>

https://jsfiddle.net/6xuvr6vw/1/

如您所见，.ruler-unit 未包含在 .horizontal-ruler 中。

Answer 1

您还需要在行中添加 vertical-align: middle

.horizontal-ruler {
  width: 100%;
  height: 25px;
  line-height: 25px;
  display: block;
  font-size: 14px;
  color: #373737;
}

.horizontal-ruler .ruler-unit {
  width: 30px;
  text-align: center;
  display: inline-block;
  line-height: 25px;
  height: 25px;
  vertical-align: middle;
}

.h-ruler-first-line,
.h-ruler-second-line {
  width: calc(50% - 15px);
  vertical-align: middle;
  margin: 12px 0;
  height: 1px;
  background-color: #373737;
  display: inline-block;
}

<div class="horizontal-ruler">
  <div class="h-ruler-first-line"></div><!--
--><div class="ruler-unit">24"</div><!--
--><div class="h-ruler-second-line"></div>
</div>

Answer 2

将vertical-align: middle添加到行中：

.h-ruler-first-line, .h-ruler-second-line {
    width: calc(50% - 15px);
    margin: 12px 0;
    height: 1px;
    background-color: #373737;
    display: inline-block;
    vertical-align: middle;
}

fiddle: https://jsfiddle.net/udwffajo/

Answer 3

您可以使用 :after 和 :before 伪元素仅用 2 div 个元素来实现它。

.horizontal-ruler{
  text-align: center;
  overflow: hidden;
  line-height: 25px;
  font-size: 14px;
  color: #373737;
  height: 25px;
}
.horizontal-ruler .ruler-unit {
  display: inline-block;
  vertical-align: top;
  position: relative;
  padding: 0 10px;
}
.horizontal-ruler .ruler-unit:before,
.horizontal-ruler .ruler-unit:after {
  background-color: #373737;
  position: absolute;
  margin-top: -1px;
  width: 9999px;
  height: 1px;
  right: 100%;
  content: '';
  top: 50%;
}
.horizontal-ruler .ruler-unit:after {
  right: auto;
  left: 100%;
}

<div class="horizontal-ruler">
  <div class="ruler-unit">24"</div>
</div>

Answer 4

您的解决方案略有不同 - 这在整个 div 上有一个底部边框和在线下方文本的相对位置，给人以两行分隔的外观文字内容。可能会更好 - 只是为了向您展示一个不需要太多代码即可达到相同效果的替代方案。

.horizontal-ruler{
  border-bottom:solid 1px #373737;
  text-align:center;
}
.ruler-unit{
  font-size:24px;
  width:30px;
  margin:0 auto;
  padding: 0 10px;
  position:relative;
  top:14px;
  background:white;
}

<div class="horizontal-ruler">
<div class="ruler-unit">24"</div>
</div>

Div 未与顶部对齐

Divs not aligned to top

html

css

vertical-alignment

css-calc