css shapes - Making jagged triangle border in CSS

Question

I have a shape with an edge like this in Photoshop:

Is it possible to make the repeated triangles as a border with CSS?

Answer 1

You can use gradients to create a zig-zag patterned background, use the ::after pseud-element to apply it like a border.

.header{
    color: white;
    background-color: #2B3A48;
    text-align: center;
}
.header::after {
    content: " ";
    display: block;
    position: relative;
    top: 0px;
    left: 0px;
    width: 100%;
    height: 36px;
    background: linear-gradient(#2B3A48 0%, transparent 0%), linear-gradient(135deg, #272220 33.33%, transparent 33.33%) 0 0%, #272220 linear-gradient(45deg, #272220 33.33%, #2B3A48 33.33%) 0 0%;
    background-repeat: repeat-x;
    background-size: 0px 100%, 9px 27px, 9px 27px;
}

<div class="header"><h1>This is a header</h1></div>