Niveus/niveus/tokens/elevation.css
Claude a19e0f205f
Depth, light and translucency without changing the API
Niveus read flat: thin sheens, short shadows, opaque grey chrome and a
painted canvas. This retunes values and component internals only; every
class and token name is unchanged, so existing pages pick it up as is.

- Canvas: a faint accent light falls across the page, so translucent
  layers have something to show through.
- Surfaces: the surface sheen runs the full height (lit top, shaded
  foot); raised and filled sheens, highlights and bevels are stronger;
  the elevation scale is deeper and softer.
- Translucency: cards, dialogs, the sidebar and tab tracks let some of
  the canvas through, with blur so busy grounds never read as texture;
  frosted and glass materials are clearer with more blur.
- Filled buttons give off a soft glow of their own color.
- Light fields are paper instead of grey wells that looked disabled.
- Fixes: navigation bars wrap and lists scroll inside them instead of
  overflowing the page on phones; choice labels sit at control size;
  disabled ghost buttons no longer grow a filled well; the color-swatch
  rule is split so neither engine drops it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019iMUTHrD8K9CSuHqsanje9
2026-10-12 20:49:22 +00:00

98 lines
4.5 KiB
CSS

/* ==========================================================================
Niveus — Elevation
--------------------------------------------------------------------------
Depth is a scale, not a free choice. Each level describes one relationship
between a surface and what sits behind it:
0 flush painted on the canvas, no separation
1 resting cards, list rows, static panels
2 raised buttons, controls, anything that reacts to a pointer
3 floating popovers, menus, dropdowns, tooltips
4 lifted dialogs, sheets, detached panels
5 overlay the topmost layer, used sparingly
Every level is built from the same three shadow colors so depth stays
consistent between appearances: an ambient contact shadow that keeps the
edge crisp, a soft penumbra for the spread, and an umbra that only appears
once a surface is genuinely far from the canvas.
========================================================================== */
:root {
--nv-elevation-0: none;
--nv-elevation-1:
0 1px 1px var(--nv-color-shadow-ambient),
0 2px 4px -1px var(--nv-color-shadow-penumbra),
0 6px 14px -8px var(--nv-color-shadow-umbra);
--nv-elevation-2:
0 1px 1px var(--nv-color-shadow-ambient),
0 3px 6px -2px var(--nv-color-shadow-penumbra),
0 10px 20px -10px var(--nv-color-shadow-umbra);
--nv-elevation-3:
0 1px 2px var(--nv-color-shadow-ambient),
0 6px 12px -4px var(--nv-color-shadow-penumbra),
0 18px 36px -12px var(--nv-color-shadow-umbra);
--nv-elevation-4:
0 1px 2px var(--nv-color-shadow-ambient),
0 10px 20px -6px var(--nv-color-shadow-penumbra),
0 30px 60px -16px var(--nv-color-shadow-umbra);
--nv-elevation-5:
0 2px 3px var(--nv-color-shadow-ambient),
0 16px 32px -8px var(--nv-color-shadow-penumbra),
0 44px 88px -20px var(--nv-color-shadow-umbra);
/* --- Inset ---------------------------------------------------------------
Recessed surfaces: fields, wells, tracks, pressed controls. */
--nv-elevation-inset-sm: inset 0 1px 2px var(--nv-color-shadow-inset);
--nv-elevation-inset-md:
inset 0 1px 1px var(--nv-color-shadow-inset),
inset 0 3px 6px -2px var(--nv-color-shadow-inset);
--nv-elevation-inset-lg:
inset 0 2px 3px var(--nv-color-shadow-inset),
inset 0 6px 12px -3px var(--nv-color-shadow-inset);
/* --- Highlight -----------------------------------------------------------
The thin catch of light along the top edge of a raised surface. This is
what makes Niveus read as material rather than as a rectangle with a
shadow. Always paired with an elevation, never used alone. */
--nv-highlight-top: inset 0 1px 0 var(--nv-color-highlight);
--nv-highlight-top-strong: inset 0 1px 0 var(--nv-color-highlight-strong);
--nv-highlight-edge:
inset 0 1px 0 var(--nv-color-highlight),
inset 0 0 0 1px var(--nv-color-border-subtle);
/* --- Bevel -----------------------------------------------------------------
The highlight's other half. A raised face is lit along its top edge and
shaded along its bottom one; together they are the bevel, and the bevel is
what makes a Niveus control look like something a finger could press.
Raised controls and surfaces take the full bevel; the highlight alone is
for things that sit flush. */
--nv-lowlight-bottom: inset 0 -1px 0 var(--nv-color-lowlight);
--nv-bevel:
inset 0 1px 0 var(--nv-color-highlight),
inset 0 -1px 0 var(--nv-color-lowlight);
/* --- Outline ---------------------------------------------------------------
The contact line: a hairline just outside a raised surface, where it meets
whatever it rests on. In dark it is near-black and does most of the
separating; in light it only softens the border beside it. */
--nv-outline: 0 0 0 1px var(--nv-color-outline);
/* --- Ledge -----------------------------------------------------------------
A recess catches light on its *lower* lip, the edge facing the viewer.
Paired with an inset shadow, it turns a field from a dark rectangle into
a well cut into the surface. */
--nv-ledge: 0 1px 0 var(--nv-color-highlight);
/* --- Focus ---------------------------------------------------------------
A contrast ring sits under the accent ring so focus stays visible on both
light and dark surfaces, and on accent-filled controls. */
--nv-focus-ring-width: 3px;
--nv-focus-ring:
0 0 0 1px var(--nv-color-focus-ring-contrast),
0 0 0 calc(1px + var(--nv-focus-ring-width)) var(--nv-color-focus-ring);
}