css垂直对齐绝对响应div内的文本

Question

我想将文本垂直居中在响应式 div 中，但如果没有新的 CSS3 技巧，我真的找不到方法......

这里有一个 fiddle :http://jsfiddle.net/M8rwn/

.iosSlider {
    position: relative;
    overflow: hidden;
    width: 100%;
    height: 100%;
}
/* slider */
.iosSlider .Slider {
    width: 100%;
    height: 100%;
}
/* slide */
.iosSlider .Slider .Slide {
    float: left;
    width: 100%;
}
.iosSlider .Slider .Slide img{
    width: 100%;
    height: auto;
} 
.slider-prevContainer {
    position: absolute;
    top: 0;
    left: 10px;
    width: 50px;
    height: 50%;
    color: #595e62;
    text-align: center;
}
.slider-nextContainer {
    position: absolute;
    top: 0;
    right: 0;
    width: 50px;
    height: 100%;
    opacity: 1;
    color: #595e62;
    background: blue;
}
.slider-next {
    position:absolute;
    height: 50%;
    width: 100%;
    top: 25%;
    text-align: center;
    vertical-align: middle;
    background: red;
    box-sizing: border-box;
    font-size: 50px;
}


#single-slider {
    float: left;
    width: 500px;
    height: 500px;
    min-width: 0;
    margin: 0;
    border: none;
    background: #000;
} 

Answer 1

好吧，我想我有一个解决方案。

调整后的 HTML:

<div class="slider-next">
   <div id='slider-next-inner'>
      >
   </div>
</div>

添加了 CSS:

#slider-next-inner{
   position:relative;
   top:50%;
   margin-top:-30px;
   /* Margin-top is 1/2 the elements height (currently it is 59px) */
}

链接:http://jsfiddle.net/M8rwn/18/