CSS3 ::selection behaves differently in FF & Chrome

问题

I'm experimenting with the ::selection pseudo-element in CSS3. In Firefox it works and looks great. My site has a dark navy blue background.

I set the selection so that it looks like this in FF.

But in chrome the same test looks like this. It seems that chrome interprets the selection as semi transparent the resultant color is nasty.

Does anyone know if it's possible to get chrome to behave the same as Firefox.

For reference here is my css:

p::-moz-selection { background:#FFFF7D; color:#032764; }
p::-webkit-selection { background:#FFFF7D; color:#032764; }
p::selection { background:#FFFF7D; color:#032764; }

Thanks

回答1:

For some reason Chrome forces it to be semi-transparent. However, you can get around this by setting the background using rgba. I have set the alpha value to be just 0.01 less than 1. Live example: http://jsfiddle.net/tw16/m8End/

p::-moz-selection {
    background:rgba(255, 255, 125, 0.99);
    color:#032764;
}
p::-webkit-selection {
    background:rgba(255, 255, 125, 0.99);
    color:#032764;
}
p::selection {
    background:rgba(255, 255, 125, 0.99);
    color:#032764;
}

回答2:

As Steven Lu has pointed out in a comment to tw16's answer, the opacity treshold is 255/256.

In other words, 0.996 will work but 0.997 will not.

Let's see it in action:

::selection
{
  background: rgba(255, 127, 0, 0.996);
  color: white;
}

::-moz-selection
{
  background: #F80;
  color: white;
}

<p>The domestic cat is a small, usually furry, domesticated, and carnivorous mammal. They are often called a housecat when kept as an indoor pet, or simply a cat when there is no need to distinguish them from other felids and felines. Cats are often valued by humans for companionship.</p>
    <img src="http://placekitten.com/g/75/300">
    <img src="http://placekitten.com/g/300/300">
    <img src="http://placekitten.com/g/150/300">
<p>A Melvin, Michigan woman was brutally attacked by a stray cat and shocking footage of the mauling has already gained a million views on YouTube.</p>
<p>The woman, who identified herself to reporters only as Maxx, endured the horrific attack November 30 but only recently realized it had been caught on her home surveillance camera.</p>
<p>The attack left her face swollen and infected and the cat named Buddy dead as officials were forced to test it for rabies.</p>

As you may see in Chrome, this obscures the images. To fix that, we need to apply specific styles to image selection, with a lower opacity:

::selection
{
  background: rgba(255, 127, 0, 0.996);
  color: white;
}

::-moz-selection
{
  background: #F80;
  color: white;
}

img::selection
{
  background: rgba(255, 127, 0, 0.8);
  color: white;
}

<p>The domestic cat is a small, usually furry, domesticated, and carnivorous mammal. They are often called a housecat when kept as an indoor pet, or simply a cat when there is no need to distinguish them from other felids and felines. Cats are often valued by humans for companionship.</p>
    <img src="http://placekitten.com/g/75/300">
    <img src="http://placekitten.com/g/300/300">
    <img src="http://placekitten.com/g/150/300">
<p>A Melvin, Michigan woman was brutally attacked by a stray cat and shocking footage of the mauling has already gained a million views on YouTube.</p>
<p>The woman, who identified herself to reporters only as Maxx, endured the horrific attack November 30 but only recently realized it had been caught on her home surveillance camera.</p>
<p>The attack left her face swollen and infected and the cat named Buddy dead as officials were forced to test it for rabies.</p>

In Firefox, there is no way to override the blue selection color on images, it seems.

来源：https://stackoverflow.com/questions/7224445/css3-selection-behaves-differently-in-ff-chrome

标签

css

css3

pseudo-element