透過・カラーサンプル

#000000 rgba(0,0,0,0.7)
#8c24c8 rgba(140,36,200,0.7)
#4d4dff rgba(77,77,255,0.7)
#0000ff rgba(0,0,100,0.7)
#ff6ec7 rgba(255,110,199,0.7)
#ff2090 rgba(255,32,144,0.7)
#ff0000 rgba(255,0,0,0.7)
#33cc33 rgba(20,80,20,0.7)
#18ff00 rgba(24,255,0,0.7)
#00ff00 rgba(0,255,102,0.8)
#83f52c rgba(131,245,44,0.7)
#fece1a rgba(254,206,26,0.7)
#ffff00 rgba(255,255,0,0.7)
#ffffff rgba(255,255,255,0.8)

ソース

<table style="background: url('https://yellowglasses.jp/wp/wp-content/uploads/2019/09/back.jpg');">
<tbody>
<tr>
<td style="color: #fff;">#000000</td>
<td style="background: rgba(0,0,0,0.7); color: #fff;">rgba(0,0,0,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#8c24c8</td>
<td style="background: rgba(140,36,200,0.7); color: #fff;">rgba(140,36,200,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#4d4dff</td>
<td style="background: rgba(77,77,255,0.7); color: #fff;">rgba(77,77,255,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#0000ff</td>
<td style="background: rgba(0,0,100,0.7); color: #fff;">rgba(0,0,100,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#ff6ec7</td>
<td style="background: rgba(255,110,199,0.7); color: #fff;">rgba(255,110,199,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#ff2090</td>
<td style="background: rgba(255,32,144,0.7); color: #fff;">rgba(255,32,144,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#ff0000</td>
<td style="background: rgba(255,0,0,0.7); color: #fff;">rgba(255,0,0,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#33cc33</td>
<td style="background: rgba(20,80,20,0.7); color: #fff;">rgba(20,80,20,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#18ff00</td>
<td style="background: rgba(24,255,0,0.7); color: #fff;">rgba(24,255,0,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#00ff00</td>
<td style="background: rgba(0,255,102,0.7); color: #fff;">rgba(0,255,102,0.8)</td>
</tr>
<tr>
<td style="color: #fff;">#83f52c</td>
<td style="background: rgba(131,245,44,0.7); color: #fff;">rgba(131,245,44,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#fece1a</td>
<td style="background: rgba(254,206,26,0.7); color: #fff;">rgba(254,206,26,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#ffff00</td>
<td style="background: rgba(255,255,0,0.7); color: #fff;">rgba(255,255,0,0.7)</td>
</tr>
<tr>
<td style="color: #fff;">#ffffff</td>
<td style="background: rgba(255,255,255,0.8); color: #fff;">rgba(255,255,255,0.8)</td>
</tr>
</tbody>
</table>


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