Double border with different color

you can add infinite borders using box-shadow using css3 suppose you want to apply multiple borders on one div then code is like:

div {
    border-radius: 4px;
    /* #1 */
    border: 5px solid hsl(0, 0%, 40%);
    
    /* #2 */
    padding: 5px;
    background: hsl(0, 0%, 20%);
    
    /* #3 */
    outline: 5px solid hsl(0, 0%, 60%);
    
    /* #4 AND INFINITY!!! (CSS3 only) */
    box-shadow:
        0 0 0 10px red,
        0 0 0 15px orange,
        0 0 0 20px yellow,
        0 0 0 25px green,
        0 0 0 30px blue;
}

I use outline a css 2 property that simply works. Check this out, is simple and even easy to animate:

.double-border {
  display: block;
  clear: both;
  background: red;
  border: 5px solid yellow;
  outline: 5px solid blue;
  transition: 0.7s all ease-in;
  height: 50px;
  width: 50px;
}
.double-border:hover {
  background: yellow;
  outline-color: red;
  border-color: blue;
}
<div class="double-border"></div>

Alternatively, you can use pseudo-elements to do so :) the advantage of the pseudo-element solution is that you can use it to space the inner border at an arbitrary distance away from the actual border, and the background will show through that space. The markup:

body {
  background-image: linear-gradient(180deg, #ccc 50%, #fff 50%);
  background-repeat: no-repeat;
  height: 100vh;
}
.double-border {
  background-color: #ccc;
  border: 4px solid #fff;
  padding: 2em;
  width: 16em;
  height: 16em;
  position: relative;
  margin: 0 auto;
}
.double-border:before {
  background: none;
  border: 4px solid #fff;
  content: "";
  display: block;
  position: absolute;
  top: 4px;
  left: 4px;
  right: 4px;
  bottom: 4px;
  pointer-events: none;
}
<div class="double-border">
  <!-- Content -->
</div>

If you want borders that are consecutive to each other (no space between them), you can use multiple box-shadow declarations (separated by commas) to do so:

body {
  background-image: linear-gradient(180deg, #ccc 50%, #fff 50%);
  background-repeat: no-repeat;
  height: 100vh;
}
.double-border {
  background-color: #ccc;
  border: 4px solid #fff;
  box-shadow:
    inset 0 0 0 4px #eee,
    inset 0 0 0 8px #ddd,
    inset 0 0 0 12px #ccc,
    inset 0 0 0 16px #bbb,
    inset 0 0 0 20px #aaa,
    inset 0 0 0 20px #999,
    inset 0 0 0 20px #888;
  /* And so on and so forth, if you want border-ception */
  margin: 0 auto;
  padding: 3em;
  width: 16em;
  height: 16em;
  position: relative;
}
<div class="double-border">
  <!-- Content -->
</div>

Tags:

Css

Border

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