CSS Opacity Example

Set Opacity level using CSS Style

Here we have given two different examples of setting opacity to different images, We have kept two different opacity levels, so you can understand the difference

opacity: 0.3;
filter: alpha(opacity=30)

opacity: 0.6;
filter: alpha(opacity=60)

On mouseover we can change the opacity to give some cool effect. here is code for changing opacity on mouseover

<style>
#img1 {
    opacity: 0.3;
    filter: alpha(opacity=30);
    width: 98%;
}
    #img1:hover {
        opacity: 1.0;
        filter: alpha(opacity=100);
    }
#img2 {
    opacity: 0.6;
    filter: alpha(opacity=60);
    width: 98%;
}
    #img2:hover {
        opacity: 1.0;
        filter: alpha(opacity=100);
    }
</style>

Remember when using the opacity property to add transparency to the background of any element, all of its child elements will become transparent as well. This will make the inner content fully transparent element, thus will be hard to read.

But there is way to keep the child element non transparent,
use background: rgba(10, 115, 219, 0.3);

div.first 
    {
        background: rgba(10, 115, 219, 0.1);
    }
div.second
    {
        background: rgba(10, 115, 219, 0.3);
    }
div.third
    {
        background: rgba(10, 115, 219, 0.6);
    }

Note: Opacity is not inherited property, but if the parent element has opacity that applies to everything within it. You cannot make any child element less transparent than the parent element.