How to Make Any Hovered Color Darker/Lighter That the Original

Dynamically change color to lighter or darker by percentage CSS

All modern browsers have had 100% filter support since January 2020. Even UC Browser for Android (instead of Chrome, on the $80 phones) supports it.

a {
    /* a nice, modern blue for links */
    color: #118bee;
}
a:active {
    /* Darken on click by 15% (down to 85%) */
    filter: brightness(0.85);
}

Additionally, you can control this dynamically with CSS variables, which have been supported by most browsers since October 2017 (excluding QQ):

:root {
    --color: #118bee;
    --hover-brightness: 1.2;
}
a {
    color: var(--color);
}
a:active {
    /* Darken on click */
    filter: brightness(var(--hover-brightness));
}

Not my project, but one that's great to look at for a real-world example of how great modern CSS can be, check out: MVP.css

Original Answer

If you're using a stack which lets you use Sass or Less, you can use the lighten function:

$linkcolour: #0000FF;

a {
  color: $linkcolour;
}

a.lighter {
  color: lighten($linkcolour, 50%);
}

There's also darken which does the same, but in the opposite direction.

Make the hovered element go darker, but all the other elements go lighter

You don't need jquery for this, it can be done with css. Try the code below, it will give you a good idea how to make what you want.

.box {  background-color: blue;  height: 50px;  width: 50px;  margin: 10px;  opacity: 0.6;}
.wrap:hover .box:hover {  opacity: 0.9;}
.wrap:hover .box:not(:hover) {  opacity: 0.4;}

<div class="wrap">  <div class="box a"></div>  <div class="box b"></div>  <div class="box c"></div>  <div class="box d"></div></div>

How to make a colour darker if light, or lighter if dark in LESS

I think the question was correctly identified as a duplicate, but for the sake of answering it correctly, here is the right answer (based on seven-phases-max's answer):

contrast(@color-input, lighten(@color-input, 10%), darken(@color-input, 10%));

You can see a working example here.

You can read more about the contrast function here.

How can I make the color of an element more dark on :hover?

You could use hsla instead of hex-colors.

example:

button{ background-color: hsla(356, 98%, 46%, 1);}
button:hover {  background-color: hsla(356, 98%, 26%, 1);}

<button>button</button>

Lighten individual background-color with hover by scss - how?

Use a mixin, like so:

.block1 {
  .backgroundsetup($color1);
}
.block2 {
  .backgroundsetup($color2);
}

.backgroundsetup($color, $amt: 40%) {
  background-color: $color;

  &:hover {
    background-color: lighten($color, $amt);
  }
}