Moving dotted border using CSS

Question

I have class that applies a dotted style border property to a text block at runtime. I am trying to find a solution, using CSS, that makes the border move like a gif image.

Answer 1

Here's a pretty flexible SCSS option:

$antlength: 50px;
$antwidth: 10px;
$antcolor: black;

@keyframes marching-ants {
    0%   {background-position: 0 0, $antlength 100%, 0 $antlength, 100% 0;}
    100% {background-position: $antlength 0, 0 100%, 0 0, 100% $antlength;}
}

.ants {
    background-image: linear-gradient(90deg, $antcolor 50%, transparent 50%),
        linear-gradient(90deg, $antcolor 50%, transparent 50%),
        linear-gradient(0, $antcolor 50%, transparent 50%),
        linear-gradient(0, $antcolor 50%, transparent 50%);
    background-repeat: repeat-x, repeat-x, repeat-y, repeat-y;
    background-size: $antlength $antwidth, $antlength $antwidth, $antwidth $antlength, $antwidth $antlength;
    animation: marching-ants 400ms infinite linear;
}