Vertical Nav Indicator Hover Effect
A vertical menu on a faint rail: hovering an item springs an accent bar onto the rail and washes a soft tint in from the left. Suits docs sidebars and settings pages.
Also known as: sidebar nav hover, vertical menu active bar, left border indicator.
HTML
<nav class="hfx-nav-vertical-bar"> <a href="#" aria-current="page">Overview</a> <a href="#">Analytics</a> <a href="#">Customers</a> <a href="#">Settings</a> </nav>
CSS
.hfx-nav-vertical-bar {
--c: var(--hfx-color, #3b82f6);
display: flex;
align-items: center;
font: 600 var(--hfx-size, 16px)/1.2 system-ui, sans-serif;
flex-direction: column;
align-items: stretch;
width: 11em;
border-left: 1px solid color-mix(in srgb, var(--c) 25%, transparent);}
.hfx-nav-vertical-bar a {
position: relative;
padding: 0.55em 1em;
border-radius: 0 0.5em 0.5em 0;
color: inherit;
text-decoration: none;
background: linear-gradient(90deg, color-mix(in srgb, var(--c) 18%, transparent), color-mix(in srgb, var(--c) 4%, transparent)) no-repeat 0 0 / 0 100%;
transition: background-size 0.35s cubic-bezier(0.65, 0, 0.35, 1), color 0.25s ease;
}
.hfx-nav-vertical-bar a::before {
content: "";
position: absolute;
left: -0.1em;
top: 0.3em;
bottom: 0.3em;
width: 0.2em;
border-radius: 1em;
background: var(--c);
transform: scaleY(0);
transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.hfx-nav-vertical-bar a:is([aria-current="page"], :hover, :focus-visible) { color: var(--c); }
.hfx-nav-vertical-bar a:is([aria-current="page"], :hover, :focus-visible)::before { transform: scaleY(1); }
.hfx-nav-vertical-bar a:is(:hover, :focus-visible) { background-size: 100% 100%; }
@media (prefers-reduced-motion: reduce) {
.hfx-nav-vertical-bar, .hfx-nav-vertical-bar *, .hfx-nav-vertical-bar::before, .hfx-nav-vertical-bar::after, .hfx-nav-vertical-bar *::before, .hfx-nav-vertical-bar *::after {
animation-duration: 0.01ms !important;
animation-iteration-count: 1 !important;
transition-duration: 0.01ms !important;
}
}Customizing this snippet
- Color: set
--hfx-coloron the element or a parent. Currently previewing#3b82f6. - Base size: set
--hfx-size. Every other dimension is inem, so the whole thing scales together. Currently previewing16px. - Speed: change the duration on the
transitionoranimationshorthand. Staggered delays are relative, so they keep their rhythm. - Reduced motion: the rule at the end of the CSS turns the motion off for people who asked their OS for less of it. Keep it.