Wave Underline
An animated SVG wave appears under each link on hover — the current page keeps the wave active.
Wave Underline the 21st of 22 designs in the 22 CSS Breadcrumbs collection. The design is implemented in pure CSS — no JavaScript required. Copy the HTML and CSS panels below into your project. Because the demo is pure CSS, it works in any framework or templating engine you happen to use. The design honours prefers-reduced-motion and uses real semantic markup, so it ships accessibility-ready out of the box.
Live preview
The code
<nav class="bc-21" aria-label="Breadcrumb">
<ol class="bc-21__list">
<li class="bc-21__item"><a class="bc-21__link" href="javascript:void(0)">Home</a></li>
<li class="bc-21__item"><a class="bc-21__link" href="javascript:void(0)">Library</a></li>
<li class="bc-21__item">
<a class="bc-21__link bc-21__link--cur" aria-current="page" href="javascript:void(0)"
>Collections</a
>
</li>
</ol>
</nav> .bc-21__list {
display: flex;
align-items: center;
list-style: none;
padding: 0;
margin: 0;
}
.bc-21__item + .bc-21__item::before {
content: "›";
padding: 0 10px;
color: rgba(255, 255, 255, 0.2);
font-size: 18px;
}
.bc-21__link {
position: relative;
font-size: 14px;
font-weight: 500;
color: rgba(255, 255, 255, 0.45);
text-decoration: none;
padding-bottom: 6px;
transition: color 0.25s;
}
.bc-21__link::after {
content: "";
position: absolute;
bottom: 0;
left: 0;
right: 0;
height: 4px;
background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 4'%3E%3Cpath d='M0 2 Q5 0 10 2 Q15 4 20 2' fill='none' stroke='%238b7fff' stroke-width='1.5'/%3E%3C/svg%3E");
background-size: 20px 4px;
background-repeat: repeat-x;
opacity: 0;
transform: translateY(4px);
transition:
opacity 0.3s,
transform 0.3s;
animation: bc21wave 1.2s linear infinite paused;
}
.bc-21__link:hover::after,
.bc-21__link--cur::after {
opacity: 1;
transform: translateY(0);
animation-play-state: running;
}
@keyframes bc21wave {
from {
background-position: 0 0;
}
to {
background-position: 20px 0;
}
}
.bc-21__link:hover {
color: rgba(255, 255, 255, 0.85);
}
.bc-21__link--cur {
color: #8b7fff;
pointer-events: none;
}