uichemy_set_section_background
One section's background band — its colour, the dark scrim over it, and how tall it is. The key is one uichemy_list_section_backgrounds shows: it identifies the template, the section and its variant, so it cannot be guessed. COLOUR: three fields move together — what the section is painted, the override that survives a section-style recompute, and the DERIVED swatch list whose token names the canvas and the export both read. Writing the first two alone is the 'colour lands in the swatch but the section stays black' fault. SCRIM: for a section whose background is a picture. "black" darkens it so text reads, "off" removes a tint the template painted itself, and "reset" leaves the template's own tint alone — 44 layouts draw one, and off is not the same as never asked. HEIGHT: a multiplier of the page's vertical rhythm, not pixels — 1.5 is half again as tall at every screen width, 1 puts the section back on the global rhythm. There is no gradient or pattern background: the product has neither, on this side or in the editor. A picture background is an image slot in the layout — set it with uichemy_set_images.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| hex | No | #RRGGBB. | |
| color | No | Instead of hex: a role ("bg", "accent", "bgLight2", "bgDark1" …) or { role, step } on its ramp — the picker's swatches. uichemy_list_section_backgrounds with shades: true lists every ramp. | |
| overlay | No | "reset" leaves the template's own tint as its author drew it. | |
| padding | No | A multiplier of the section rhythm. 1 resets. | |
| projectId | Yes | ||
| sectionKey | Yes | A key from uichemy_list_section_backgrounds. | |
| overlayOpacity | No | How dark, for overlay "black" only. Omitted follows the site default. |