<style type="text/css">
.op {
zoom:1;
opacity:0.5;
-moz-opacity: 0.5;
filter:alpha(opacity=50);
}
.op_inline {
display:inline;
zoom:1;
opacity:0.5;
-moz-opacity: 0.5;
filter:alpha(opacity=50);
}
.op_block {
display:block;
zoom:1;
opacity:0.5;
-moz-opacity: 0.5;
filter:alpha(opacity=50);
}
.op_inlineblock {
display:inline-block;
zoom:1;
opacity:0.5;
-moz-opacity: 0.5;
filter:alpha(opacity=50);
}
.relative {
position:relative;
}
<style>
<p>---
<Element class="testclass">ABC
<span class="relative">abc</span>
</Element>
<Element style="testclass">あいう
<span>ぁぃぅ</span>
</Element>
---</p>
---
---
ABCabc
あいうぁぃぅ
------
ABCabc
あいうぁぃぅ
------
ABCabc
あいうぁぃぅ
------ ABCabcあいうぁぃぅ ---
--- ABCabcあいうぁぃぅ ---
--- ABCabcあいうぁぃぅ ---