How do I give text or an image a transparent backg

Question

Is it possible, using CSS only, to make the background of an element semi-transparent but have the content (text & images) of the element opaque?

I'd like to accomplish this without having the text and the background as two separate elements.

When trying:

p {
  position: absolute;
  background-color: green;
  filter: alpha(opacity=60);
  opacity: 0.6;
}

span {
  color: white;
  filter: alpha(opacity=100);
  opacity: 1;
}

<p>
  <span>Hello world</span>
</p>

It looks like child elements are subjected to the opacity of their parents, so opacity:1 is relative to the opacity:0.6 of the parent.

Answer 1

If you're using Less, you can use fade(color, 30%).

Answer 2

You can do with rgba color code using css like this example given bellow.

.imgbox img{
  height:100px;
  width:200px;
  position:relative;
}
.overlay{
  background:rgba(74, 19, 61, 0.4);
  color:#fff;
  text-shadow:0px 2px 5px #000079;
  height:100px;
  width:300px;
  position:absolute;
  top:10%;
  left:25%;
  padding:25px;
}

<div class"imgbox">
<img src="http://www.bhmpics.com/wallpapers/little_pony_art-800x480.jpg">
  <div class="overlay">
    <p>This is Simple Text.</p>
  </div>
</div>

Answer 3

You can use RGB color with opacity like this color code in RGB (63,245,0) and add opacity like (63,245,0,0.5) and also add RGBA replace RGB. A use for opacity

div{
  background:rgba(63,245,0,0.5);
  }

Answer 4

There is a trick to minimize the markup: Use a pseudo element as the background and you can set the opacity to it without affecting the main element and its children:

DEMO

Output:

Relevant code:

p {
  position: relative;
}
p:after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: #fff;
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=50)";
  opacity: .6;
  z-index: -1;
}
/*** The following is just for demo styles  ***/

body {
  background: url('http://i.imgur.com/k8BtMvj.jpg') no-repeat;
  background-size: cover;
}
p {
  width: 50%;
  padding: 1em;
  margin: 10% auto;
  font-family: arial, serif;
  color: #000;
}
img {
  display: block;
  max-width: 90%;
  margin: .6em auto;
}

<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed a ligula ut nunc dignissim molestie.
  <img src="http://i.imgur.com/hPLqUtN.jpg" alt="" />
</p>

Browser support is Internet Explorer 8 and later.

• pseudo elements
• opacity

Answer 5

The easiest method would be to use a semi-transparent background PNG image.

You can use JavaScript to make it work in Internet Explorer 6 if you need to.

I use the method outlined in Transparent PNGs in Internet Explorer 6.

Other than that,

you could fake it using two side-by-side sibling elements - make one semi-transparent, then absolutely position the other over the top?

Answer 6

This method allows you to have an image in the background and not only a solid color, and can be used to have transparency on other attributes such as borders. No transparent PNG images are required.

Use :before (or :after) in CSS and give them the opacity value to leave the element at its original opacity. Thus you can use :before to make a faux element and give it the transparent background (or borders) you want and move it behind the content you want to keep opaque with z-index.

An example (fiddle) (note that the DIV with class dad is just to provide some context and contrast to the colors, this extra element is actually not needed, and the red rectangle is moved a bit down and to the right to leave visible the background behind the fancyBg element):

<div class="dad">
    <div class="fancyBg">
        Test text that should have solid text color lets see if we can manage it without extra elements
    </div>
</div>

with this CSS:

.dad {
    background: lime; border: 1px double black; margin: 1ex 2ex;
    padding: 0.5ex; position: relative; -k-z-index: 5;
}
.fancyBg {
    border: 1px dashed black; position: relative; color: white; font-weight: bold;
    z-index: 0; /*background: black;*/
}
.fancyBg:before {content:'-'; display: block;
    position: absolute; background: red; opacity: .5;
    top: 2ex; right: -2ex; bottom: -2ex; left: 2ex;
    /*top: 0; right: 0; bottom: 0; left: 0;*/
    z-index: -1;
}

In this case .fancyBg:before has the CSS properties you want to have with transparency (red background in this example, but can be an image or borders). It's positioned as absolute to move it behind .fancyBg (use values of zero or whatever is more appropriate for your needs).