How can I create a menu which only its background is transparent? The text should keep opaque (opacity: 1)
If I set
li:hover {
opacity: 0.5
}
The whole list item becomes transparent. How do I fix that?
There is a new value in CSS3 called "rgba" that allows you to use a transparent color as a background color. For instance:
li:hover {
background-color: rgba(255, 255, 255, 0.5);
}
I'm fairly sure that should work, though I just wrote the code on the spot so it may not. This will, however, give your menu a white-ish tinge to it. If you want to read more about RGBA, though, go here: http://css-tricks.com/rgba-browser-support/
You’ll need to use either a transparent PNG image, or an rgba colour value, for the <li>’s background, e.g.:
li:hover {
background-color: rgba(0, 0, 0, 0.5);
}
Or:
li:hover {
background: url(a-nice-semi-transparent-png-image.png);
/* Supplying just the image file here will make the browser repeat the image
file vertically and horizontally, thus taking up all the space, just like a
colour would */
}
I don't think, that's possible, try this example: http://jsfiddle.net/578SV/
You can't. The transparency level gets handed down to all child elements.
Your options:
Place another element on top of the li, possibly using position: absolute, that has a normal opacity setting
Use a PNG file with Alpha transparency to create the opacity effect (Will need workarounds to work in IE6)
Use the new rgba colour property as shown by #hatkirby, if you can live with the incomplete browser support
Related
I am trying to set the color for a header on a wordpress website to transparent, so that the logo and menu icon show over the website's other elements and do not have their own background.
My issue is the following. The CSS that sets the header color is the following, in my app.css file:
header.dark-header {
background-color:#252627;
border-color:transparent;
border-bottom:0;
}
If I set that to transparent, the background actually turns white and is not transparent.
Images explaining the issue: https://imgur.com/a/XJta1p1
Website demo: http://security4.forebet.ro
I have no idea what to do or why this is happening. Anybody?
Setting background-color: transparent; should do the trick.
So like this:
header.dark-header {
background-color: transparent;
border-color:transparent;
border-bottom:0;
}
transparent is the default value for background-color, so if the element's background turns white when you use it, the default is probably being overridden by a parent element where background-color has an explicitly set value. Short of digging through your stylesheet and changing this (probably the best solution), you can use the CSS rgba() function to explicitly set the header's background opacity to zero like this:
header.dark-header {
background-color: rgba(0, 0, 0, 0);
border-color: rgba(0, 0, 0, 0);
border-bottom:0;
}
Although be advised that browser support for the rgba() function is still a little spotty.
Alright So here is my CSS style sheet.
#mainheader,#content{
opacity:0.35;
text-align:center;
background-color:#000000;
border-top-style:ridge;
border-left-style:ridge;
border-right-style:ridge;
border-bottom-style:ridge;
}
And as you can see it's a box that's see through, but has a small black background making text look fuzzy. Example.
http://i.stack.imgur.com/18dOZ.png
When I take away that background color I get more clear text like this...
http://i.stack.imgur.com/ixLva.png
Alright So what i'm trying to say it what can I write to have that text above that box being very clear text and not with it's dark opacity.
If you want to use CSS3, try:
background-color: rgba(0,0,0,0.35);
instead of opacity.
http://jsfiddle.net/vsZtM/
References from W3.org about RGBA:
http://www.w3.org/TR/2003/CR-css3-color-20030514/#rgba-color
http://www.w3.org/wiki/CSS3/Color/RGBA
Instead of opacity, change background of containers with an alpha channel:
#mainheader,#content {
background: rgba(0,0,0,0.35);
}
Where last param is the opacity.
Opacity changes the opacity for the entire element, while background:rgba(0,0,0,.35) will change only the background color.
You should try using rgba instead of opacity like so:
background-color: rgba(0,0,0,0.35);
Note: this is CSS3 and will only work in IE9 and up, so for other versions you should provide a fallback like so:
background-color: #000;
background-color: rgba(0,0,0,0.35);
You can set the background-color as an rgba value, and leave off the opacity in your CSS statement. For example:
#mainheader,#content{
text-align:center;
background-color: rgba(0, 0, 0, .35);
border-top-style:ridge;
border-left-style:ridge;
border-right-style:ridge;
border-bottom-style:ridge;
}
This will let your text stay fully opaque, while your background is semi-transparent. As a note, however, this will not work in Internet Explorer 8 and below -- it will be a solid background.
The background-color of my body is #ffffff. And I have a div that I need is colored but it needs to be transparent or see through. Is it possible to do this using CSS3 or do I have to use images to achieve this?
body {
background-color: #ffffff;
}
.box {
background-color: #999999;
background-image: linear-gradient(to top, #999999 0%, #444444 100%) !important;
opacity: 0.7;
}
Update:
If you go here: http://pinesframework.org/pnotify/#demos-simple and look for the demo for Transparent Success you can see how the pop-up looks see through on a white background. I need to do something like that without using an image as they are using one.
It sounds like you want an alpha transparent background color. If that's the case, you can use RGBA colors, rather than a solid hex value and an opacity property. This way, only the background will have transparency, not the content.
In your case it would be:
.box {
background-color: rgba(255,0,0,0.7);
}
You can also specify a fallback color to browsers that don't support RGBA (IE 8 and older), or create a PNG image with the color fill you want. My vote is toward progressive enhancement, and just specify an alternate color for browsers that don't understand RGBA:
.box {
background-color: #ff4c4c;
background-color: rgba(255,0,0,0.7);
}
UPDATED: Per your comment below, this question appears to be a duplicate of CSS - Opaque text on low opacity div?.
You need to change the opacity of the background instead of the element:
.box {
rgba(255,0,0,0.6);
}
Or, since you are using a gradient, I would use this:
Ultimate CSS Gradient Generator
It will allow you to do semi-transparent backgrounds with a gradient.
I am currently wondering which is the best CSS property to use, Opacity or RGBa? More specifically I am trying to recreate something similar to the famous BBC Home page slider, and it got me thinking why they use Opacity.
In my version I have came across using the following two versions of code:
.left-button {
background: rgb(255, 255, 255) url('../images/left-arrow.png') no-repeat; //FALLBACK
background: rgba(255, 255, 255, 0.4) url('../images/left-arrow.png') no-repeat;
}
or
.left-button {
background: #fff url('../images/left-arrow.png') no-repeat; //FALLBACK
opacity: 0.4;
}
Obviously the second one makes the actual button image opaque too, which is why I assume the BBC has made separate buttons and background masks for the buttons (which in my opinion is unnecessary additional markup).
I'd like to use the first version with RGBa though. Would anyone care to point out why one is better than the other and if there is any compatibility issues I am unaware of?
Opacity is inherited to all child items, RGBa is not. If a child item has a lesser or no opacity, use RGBa.
IE8 and lower does not support RGBa, so you may need an opacity back-up plan.
Neither one is "better" because they do different things, so it depends on what you're trying to accomplish.
opacity sets the opacity for the entire element and all of its contents (text, inline images, etc). RGBa is a way to define a color with a certain level of alpha transparency.
So let's say you have a div:
<div>Hello!</div>
This will make the entire div and its contents ("Hello!") 50% opaque:
div {
background: #000;
color: #fff;
opacity: 0.5;
}
Whereas this will make just the background of the div 50% opaque, while leaving the text at 100% opaque pure white:
div {
background: rgba(0, 0, 0, 0.5);
color: #fff;
}
I want to set Opacity of div's background without affecting contained element in IE 8. have a any solution and don't answer to set 1 X 1 .png image and set opacity of that image because I am using dynamic opacity and color admin can change that
I used that but not working in IE 8
#alpha {
filter: alpha(opacity=30);
-moz-opacity: 0.3;
-khtml-opacity: 0.3;
opacity: 0.3;
}
and
rgba(0,0,0,0.3)
also.
The opacity style affects the whole element and everything within it. The correct answer to this is to use an rgba background colour instead.
The CSS is fairly simple:
.myelement {
background: rgba(200, 54, 54, 0.5);
}
...where the first three numbers are the red, green and blue values for your background colour, and the fourth is the 'alpha' channel value, which works the same way as the opacity value.
See this page for more info: http://css-tricks.com/rgba-browser-support/
The down-side, is that this doesn't work in IE8 or lower. The page I linked above also lists a few other browsers it doesn't work in, but they're all very old by now; all browsers in current use except IE6/7/8 will work with rgba colours.
The good news is that you can force IE to work with this as well, using a hack called CSS3Pie. CSS3Pie adds a number of modern CSS3 features to older versions of IE, including rgba background colours.
To use CSS3Pie for backgrounds, you need to add a specific -pie-background declaration to your CSS, as well as the PIE behavior style, so your stylesheet would end up looking like this:
.myelement {
background: rgba(200, 54, 54, 0.5);
-pie-background: rgba(200, 54, 54, 0.5);
behavior: url(PIE.htc);
}
[EDIT]
For what it's worth, as others have mentioned, you can use IE's filter style, with the gradient keyword. The CSS3Pie solution does actually use this same technique behind the scenes, but removes the need for you to mess around directly with IE's filters, so your stylesheets are much cleaner. (it also adds a whole bunch of other nice features too, but that's not relevant to this discussion)
it's simple only you have do is to give
background: rgba(0,0,0,0.3)
& for IE use this filter
background: transparent;
zoom: 1;
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr=#4C000000,endColorstr=#4C000000); /* IE 6 & 7 */
-ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorstr=#4C000000,endColorstr=#4C000000)"; /* IE8 */
you can generate your rgba filter from here http://kimili.com/journal/rgba-hsla-css-generator-for-internet-explorer/
opacity on parent element sets it for the whole sub DOM tree
You can't really set opacity for certain element that wouldn't cascade to descendants as well. That's not how CSS opacity works I'm afraid.
What you can do is to have two sibling elements in one container and set transparent one's positioning:
<div id="container">
<div id="transparent"></div>
<div id="content"></div>
</div>
then you have to set transparent position: absolute/relative so its content sibling will be rendered over it.
rgba can do background transparency of coloured backgrounds
rgba colour setting on element's background-color will of course work, but it will limit you to only use colour as background. No images I'm afraid. You can of course use CSS3 gradients though if you provide gradient stop colours in rgba. That works as well.
But be advised that rgba may not be supported by your required browsers.
Alert-free modal dialog functionality
But if you're after some kind of masking the whole page, this is usually done by adding a separate div with this set of styles:
position: fixed;
width: 100%;
height: 100%;
z-index: 1000; /* some high enough value so it will render on top */
opacity: .5;
filter: alpha(opacity=50);
Then when you display the content it should have a higher z-index. But these two elements are not related in terms of siblings or anything. They're just displayed as they should be. One over the other.
Try setting the z-index higher on the contained element.
What about this approach:
<head>
<style type="text/css">
div.gradient {
color: #000000;
width: 800px;
height: 200px;
}
div.gradient:after {
background: url(SOME_BACKGROUND);
background-size: cover;
content:'';
position:absolute;
top:0;
left:0;
width:inherit;
height:inherit;
opacity:0.1;
}
</style>
</head>
<body>
<div class="gradient">Text</div>
</body>
It affects the whole child divs when you use the opacity feature with positions other than absolute. So another way to achieve it not to put divs inside each other and then use the position absolute for the divs. Dont use any background color for the upper div.
Maybe there's a more simple answer, try to add any background color you like to the code, like background-color: #fff;
#alpha {
background-color: #fff;
opacity: 0.8;
filter: alpha(opacity=80);
}
Use RGBA or if you hex code then change it into rgba. No need to do some presodu element css.
function hexaChangeRGB(hex, alpha) {
var r = parseInt(hex.slice(1, 3), 16),
g = parseInt(hex.slice(3, 5), 16),
b = parseInt(hex.slice(5, 7), 16);
if (alpha) {
return "rgba(" + r + ", " + g + ", " + b + ", " + alpha + ")";
} else {
return "rgb(" + r + ", " + g + ", " + b + ")";
}
}
hexaChangeRGB('#FF0000', 0.2);
css ---------
background-color: #fff;
opacity: 0.8;
OR
mycolor = hexaChangeRGB('#FF0000', 0.2);
document.getElementById("myP").style.background-color = mycolor;