jquery - HTML/CSS : display table-cell not centering text in firefox

Question

将鼠标悬停在一个 div 上会淡化到顶部的另一个 div，不透明度和一些文本在 div 内完美居中。这在除 firefox 之外的所有浏览器中都可以正常工作。
这是一个 jsfiddle 演示:http://jsfiddle.net/neal_fletcher/WHCNF/

HTML:

<div class="grid-block identity" style="background-image: url('http://placekitten.com/380/250');">
    <div class="grid-block-text-hover-wrap">
    <div class="grid-block-text-wrap">
        <div class="grid-block-text-title">TITLE</div>
        <div class="grid-block-text-subtitle">SUBTITLE</div>
    </div>
    </div>
</div>

CSS:

.grid-block {
    position: absolute;
    width: 380px; height: 250px;
    margin-left: 25px; margin-right: 25px;
    margin-bottom: 50px;
    font-family: 'times';
    text-align: center;
    background: no-repeat 50% 50%;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
    cursor: pointer;
    display: table; vertical-align: middle;
}

.grid-block-text-hover-wrap {
    position: absolute; 
    width: 100%; height: 100%; 
    background: rgba(0,0,0,0.75);
    display: table;
    vertical-align: middle;
}

.grid-block-text-hover-wrap .grid-block-text-wrap {
    color: white; 
}

.grid-block .grid-block-text-wrap {
    display: table-cell; vertical-align: middle;
    width: 100%; height: 100%;
}

.grid-block-text-wrap {
    margin-left: 50px; margin-right: 50px;
}

.grid-block-text-title {
    position: relative;
    margin-top: 7px;
    margin-bottom: 20px;
    text-transform: uppercase;
}

.grid-block-text-hover-wrap .grid-block-text-title {
    font-size: 16px;
    line-height: 25px;
    letter-spacing: 2px !important;
}

.grid-block-text-subtitle {
    position: relative;
    font-size: 12px;
    letter-spacing: 2px !important;
    text-transform: uppercase;
}

如您所见，.grid-block-text-hover-wrap 在悬停时淡入淡出，但出于某种原因，在 firefox 中，此 div 显示不正确且未将文本居中应该。我不明白为什么会这样。任何建议将不胜感激!

Answer 1

尝试替换 height: 100%;宽度:100% 和 宽度:380px；高度:250px。看看新的 fiddle :http://jsfiddle.net/WHCNF/1/