Niveus/niveus/components/navigation.css
Nexoniarz 2e956cec42 Stop snapshotting the page; own the wheel gesture; one-row phone nav
Selection markers, tab panels, brand changes and theme changes no longer use
a view transition. The page snapshot could not blur what sits behind frosted
glass, so every frosted surface went clear for the length of the change.
nv.transition now measures the marker before and after, and animates the
marker itself (FLIP); arriving content animates on its own; colours fade on
their own surfaces. Verified in Firefox: no view transition is ever started.

Time picker: wheels take every pointer type (mouse, pen, touch) with
touch-action: none, so a phone, a browser's phone mode and a desktop behave
alike. The rubber-band is capped at about 40% of a row (a whole row made the
neighbour look selected). Each wheel has its own frame slot, so one wheel can
no longer swallow another's last scroll event. Switching 24H / AM / PM
happens when the wheel settles, and the hours animate into the new layout.

Carousel arrows are frosted glass, as anything floating over content should be.
At phone width the top bar keeps to one row and its link list scrolls.

GUIDELINES.md records the new cross-engine rules.

check.py, build.py and build.py --check pass.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
2026-10-28 10:09:14 +01:00

400 lines
12 KiB
CSS

/* ==========================================================================
Niveus — Navigation
--------------------------------------------------------------------------
.nv-nav horizontal bar, frosted, sticky by default
.nv-nav--vertical sidebar
.nv-nav--plain solid instead of frosted
.nv-nav__brand / __list / __item / __section / __spacer
.nv-nav-tabs in-page tab strip with a sliding indicator
Navigation is chrome: it sits above content rather than in it. That is why
the bar is frosted and bevelled — the blur is not decoration, it is the
signal that content is passing underneath. A sidebar that scrolls with the page is not
chrome, so .nv-nav--vertical drops the translucency by default.
========================================================================== */
.nv-nav {
position: sticky;
inset-block-start: 0;
z-index: 10;
display: flex;
align-items: center;
flex-wrap: wrap;
gap: var(--nv-space-2) var(--nv-space-4);
padding: var(--nv-space-2) var(--nv-space-4);
min-block-size: var(--nv-control-height-lg);
background-color: var(--nv-material-frosted-bg);
background-image: var(--nv-sheen-raised);
border-block-end: var(--nv-border-width) solid var(--nv-color-border-subtle);
/* The travelling selection marker sits behind its item at z-index -1; the
bar has to be its own stacking context or the marker would fall behind
the bar's background and disappear. */
isolation: isolate;
box-shadow: var(--nv-bevel);
backdrop-filter: var(--nv-backdrop-frosted);
-webkit-backdrop-filter: var(--nv-backdrop-frosted);
transition: var(--nv-transition-surface);
}
/* The bar only earns a shadow once something is behind it. Set data-scrolled
from the application on scroll. */
.nv-nav[data-scrolled] {
box-shadow: var(--nv-bevel), var(--nv-elevation-2);
transition: box-shadow var(--nv-duration-normal) var(--nv-ease-standard);
}
.nv-nav--plain {
background-color: var(--nv-color-surface);
background-image: var(--nv-sheen-raised);
backdrop-filter: none;
-webkit-backdrop-filter: none;
}
.nv-nav--static {
position: static;
}
/* On a phone the bar keeps to one row. Wrapping put the controls on a second
line that sat over the links, and with glass behind it that read as a
collision. Instead the list gives way: it takes the room that is left and
scrolls sideways inside the bar, and everything else keeps its size. */
@media (max-width: 40rem) {
.nv-nav:not(.nv-nav--vertical):not(.nv-nav--inline) {
flex-wrap: nowrap;
gap: var(--nv-space-2);
padding-inline: var(--nv-space-3);
}
.nv-nav:not(.nv-nav--vertical):not(.nv-nav--inline) > * {
flex-shrink: 0;
}
.nv-nav:not(.nv-nav--vertical):not(.nv-nav--inline) > .nv-nav__list {
flex: 1 1 0;
flex-shrink: 1;
overflow-x: auto;
}
.nv-nav:not(.nv-nav--vertical):not(.nv-nav--inline) > .nv-nav__spacer {
display: none;
}
}
/* A navigation group used inside content rather than as page chrome: no bar,
no border, no blur — just the items and their travelling selection. */
.nv-nav--inline {
position: static;
display: inline-flex;
min-block-size: 0;
padding: var(--nv-space-1);
background-color: transparent;
border-block-end: 0;
background-image: none;
box-shadow: none;
backdrop-filter: none;
-webkit-backdrop-filter: none;
}
.nv-nav__brand {
display: flex;
align-items: center;
gap: var(--nv-space-2);
font: var(--nv-font-title);
letter-spacing: var(--nv-letter-spacing-tight);
color: var(--nv-color-text-primary);
text-decoration: none;
padding-inline: var(--nv-space-1);
}
.nv-nav__list {
display: flex;
align-items: center;
gap: var(--nv-space-1);
margin: 0;
padding: 0;
list-style: none;
min-inline-size: 0;
/* On a narrow screen a long list scrolls inside the bar instead of pushing
the page sideways. */
max-inline-size: 100%;
overflow-x: auto;
scrollbar-width: none;
}
.nv-nav__list::-webkit-scrollbar {
display: none;
}
.nv-nav__spacer {
flex: 1;
}
/* --- Item --------------------------------------------------------------------
Items are flat until they are touched. The active item is the only one with
material, which keeps the bar quiet while still answering "where am I". */
.nv-nav__item {
/* Rides above a travelling marker once niveus.js has given it a name. */
view-transition-class: nv-carried;
position: relative;
display: flex;
align-items: center;
gap: var(--nv-space-2);
padding: var(--nv-space-2) var(--nv-space-3);
min-block-size: var(--nv-control-height-md);
border: var(--nv-border-width) solid transparent;
border-radius: var(--nv-radius-md);
background-color: transparent;
color: var(--nv-color-text-secondary);
font: var(--nv-font-label);
text-decoration: none;
white-space: nowrap;
cursor: pointer;
transition: var(--nv-transition-control);
}
@media (hover: hover) {
.nv-nav__item:hover {
background-color: var(--nv-color-surface-hover);
color: var(--nv-color-text-primary);
}
}
.nv-nav__item:active {
background-color: var(--nv-color-surface-active);
box-shadow: var(--nv-elevation-inset-sm);
transition-duration: var(--nv-duration-instant);
}
.nv-nav__item:focus-visible {
outline: none;
box-shadow: var(--nv-focus-ring);
}
/* Selection is a material that *moves*. The emphasis lives in a pseudo-element
rather than on the item itself, and carries a view-transition-name: when the
selection changes inside a transition, the browser interpolates the marker's
old box into its new one, so the highlight slides from the previous item to
the next instead of blinking out and in somewhere else.
Only one item in a group may be selected at a time — that is what keeps the
name unique. A page with several selection groups must give each its own
--nv-selection-name, or the duplicate name aborts the transition. */
/* Selection changes color and gains material — but not weight. Bolding the
selected item re-measures its text, which reflows every item beside it on
each change, and makes the old and new labels cross-fade against each other
at different widths. The pill is the cue; the weight was costing a flicker
for nothing. */
.nv-nav__item[aria-current],
.nv-nav__item--active,
.nv-nav__item[aria-selected="true"] {
color: var(--nv-color-text-primary);
}
.nv-nav__item[aria-current]::before,
.nv-nav__item--active::before,
.nv-nav__item[aria-selected="true"]::before {
content: "";
position: absolute;
inset: 0;
z-index: -1;
background-color: var(--nv-color-surface-elevated);
background-image: var(--nv-sheen-raised);
border: var(--nv-border-width) solid var(--nv-color-border-subtle);
border-radius: inherit;
box-shadow: var(--nv-bevel), var(--nv-outline), var(--nv-elevation-1);
view-transition-class: nv-travelling;
}
/* The marker is named only while its own group is changing (niveus.js sets
data-nv-travelling for the length of the transition). A permanent name
would lift every marker on the page out of the page snapshot on every
transition, theme changes included. */
[data-nv-travelling] .nv-nav__item[aria-current]::before,
[data-nv-travelling] .nv-nav__item--active::before,
[data-nv-travelling] .nv-nav__item[aria-selected="true"]::before {
view-transition-name: var(--nv-selection-name);
}
/* Hovering an already-selected item should not restate the emphasis. */
@media (hover: hover) {
.nv-nav__item[aria-current]:hover,
.nv-nav__item--active:hover,
.nv-nav__item[aria-selected="true"]:hover {
background-color: transparent;
}
}
.nv-nav__item[aria-disabled="true"] {
color: var(--nv-color-text-disabled);
pointer-events: none;
}
.nv-nav__icon {
inline-size: 1.15em;
block-size: 1.15em;
flex: none;
opacity: 0.85;
}
.nv-nav__badge {
margin-inline-start: auto;
padding-inline: var(--nv-space-1-5);
min-inline-size: var(--nv-space-5);
block-size: var(--nv-space-5);
display: inline-flex;
align-items: center;
justify-content: center;
background-color: var(--nv-color-accent-subtle);
color: var(--nv-color-accent-text);
border-radius: var(--nv-radius-full);
font: var(--nv-font-caption);
font-size: var(--nv-font-size-2xs);
font-weight: var(--nv-font-weight-semibold);
}
/* --- Vertical ------------------------------------------------------------------ */
.nv-nav--vertical {
position: sticky;
inset-block-start: 0;
flex-direction: column;
align-items: stretch;
gap: var(--nv-space-1);
inline-size: 15rem;
block-size: 100svh;
flex-wrap: nowrap;
padding: var(--nv-space-4) var(--nv-space-3);
/* A sidebar is a pane of the canvas rather than chrome over content, so it
stays mostly opaque — but it lets the light of the canvas through, which
is what stops it reading as a grey slab beside the page. */
background-color: color-mix(in oklab, var(--nv-color-background-subtle) 72%, transparent);
background-image: var(--nv-sheen-surface);
backdrop-filter: var(--nv-backdrop-frosted);
-webkit-backdrop-filter: var(--nv-backdrop-frosted);
border-block-end: 0;
border-inline-end: var(--nv-border-width) solid var(--nv-color-border-subtle);
box-shadow: none;
overflow-y: auto;
}
.nv-nav--vertical .nv-nav__list {
flex-direction: column;
align-items: stretch;
gap: var(--nv-space-0-5);
}
.nv-nav--vertical .nv-nav__item {
justify-content: flex-start;
}
.nv-nav--vertical .nv-nav__brand {
padding: var(--nv-space-2) var(--nv-space-3);
margin-block-end: var(--nv-space-3);
}
/* Engraved, like .nv-overline: a section marks a region, it is not read. */
.nv-nav__section {
padding: var(--nv-space-4) var(--nv-space-3) var(--nv-space-1-5);
font: var(--nv-font-engraved);
letter-spacing: var(--nv-letter-spacing-engraved);
text-transform: uppercase;
color: var(--nv-color-text-tertiary);
}
.nv-nav__section:first-child {
padding-block-start: 0;
}
/* --- Tabs ------------------------------------------------------------------------
For switching views inside a page, not for moving between pages. The strip
itself is inset, so the selected tab reads as lifted out of the track. */
.nv-nav-tabs {
display: inline-flex;
align-items: center;
max-inline-size: 100%;
gap: var(--nv-space-0-5);
padding: var(--nv-space-1);
background-color: color-mix(in oklab, var(--nv-color-surface-inset) 80%, transparent);
border: var(--nv-border-width) solid var(--nv-color-border-subtle);
border-radius: var(--nv-radius-md);
box-shadow: var(--nv-elevation-inset-md), var(--nv-ledge);
overflow-x: auto;
scrollbar-width: none;
isolation: isolate;
}
.nv-nav-tabs::-webkit-scrollbar {
display: none;
}
.nv-nav-tabs .nv-nav__item {
border-radius: var(--nv-radius-sm);
min-block-size: var(--nv-control-height-sm);
padding-block: var(--nv-space-1);
}
/* Tabs are a selection group of their own, so they get their own marker name;
sharing the navigation bar's would mean two visible elements with the same
view-transition-name. */
.nv-nav-tabs {
--nv-selection-name: nv-tabs-selection;
}
.nv-nav-tabs .nv-nav__item[aria-selected="true"]::before {
border-radius: var(--nv-radius-sm);
}
/* --- Panels ----------------------------------------------------------------------
Switching tabs should feel like moving through one surface rather than
swapping the interface. nv.selectTab() gives the outgoing and incoming
panels one shared name for the length of the change, so they hand over
inside the same box — and slide with the direction of travel. The class is
what picks up the content animation in continuity.css. */
.nv-tab-panel {
view-transition-class: nv-content;
}
/* --- Breadcrumbs -------------------------------------------------------------------- */
.nv-breadcrumbs {
display: flex;
align-items: center;
gap: var(--nv-space-2);
margin: 0;
padding: 0;
list-style: none;
font: var(--nv-font-caption);
color: var(--nv-color-text-tertiary);
}
.nv-breadcrumbs li + li::before {
content: "/";
margin-inline-end: var(--nv-space-2);
color: var(--nv-color-border-strong);
}
.nv-breadcrumbs a {
color: var(--nv-color-text-secondary);
text-decoration: none;
}
.nv-breadcrumbs a:hover {
color: var(--nv-color-text-primary);
}
.nv-breadcrumbs [aria-current] {
color: var(--nv-color-text-primary);
font-weight: var(--nv-font-weight-medium);
}