Generate random color with pure CSS (no javascript

2019-04-03 12:27发布

问题:

Is it possible to generate random color with pure CSS and without using javascript? It's probably impossible but I'm still curious.

回答1:

I found for you something here, but it uses PHP. I think it's impossible with plain CSS.



回答2:

This isn't really possible in pure CSS.

However, using a pre-processor like SASS (example) or LESS (example) can generate random colors for you because they are built using scripting languages.


One side note that may help readers in the future is the possibility for using CSS variables. We can declare a CSS variable by saying

element {
  --main-bg-color: brown;
}

and use it like so:

element {
  background-color: var(--main-bg-color);
}

Now we can change it using JS:

// From http://stackoverflow.com/a/5365036/2065702
var randomColor = "#"+((1<<24)*Math.random()|0).toString(16); 

document.documentElement.style.setProperty('main-bg-color', randomColor);

Or you could use a completely different way of selecting a random color (like user input). This allows for possibilities like theming. One thing you have to consider is browser support because it's not great right now.



回答3:

Not really. Dynamism can only be implemented with the support of scripting.



回答4:

according to this site, http://blog.codepen.io/2013/08/26/random-function-in-sass/ its possible but not with pure css



回答5:

<body style='background-color:<?php printf( "#%06X\n", mt_rand( 0, 0x222222 )); ?>'>

Using PHP



回答6:

Not exactly random but with CSS:

Step 1 - Select queried backgrounds, order them in sequence and adjust the frequency

    @keyframes bgrandom {
    0% { background: linear-gradient(90deg, rgba(255,255,255,0.98) 50%, rgba(255,255,255,0.96) 0%); }
    50% { background: linear-gradient(90deg, rgba(255,255,255,0.98) 50%, rgba(255,255,255,0.96) 0%); }

    55% { background: linear-gradient(90deg,  rgba(255,255,255,0.96) 50%, rgba(255,255,255,0.98) 0%); }
    80% { background: linear-gradient(90deg, rgba(255,255,255,0.96)  50%, rgba(255,255,255,0.98) 0%); }

    85% { background: linear-gradient(90deg, rgba(255,255,255,0.96) 50%, rgba(255,255,255,0.94) 0%); }
    100% { background: linear-gradient(90deg, rgba(255,255,255,0.96) 50%, rgba(255,255,255,0.94) 0%); }
    }

Step 2 - Launch the animation(length animationName repeatMode)

    #element{  animation: 1.2s bgrandom infinite; }

Easy to use, customize and works great. Similar technique can be used for sliders, spinners, etc.