WordPress FSE Theme
The block theme that doesn’t get in the way.
Jexii Builder is a brand-agnostic FSE chassis — all design tokens in theme.json, all color schemes as block styles, all brand decisions deferred to style variations or child themes. Ship clean sites without a line of custom CSS.
- fse native
- design tokens
- style variations
- block styles
- atmosphere layer
- fluid type
- pattern library
- child theme ready
- prose-safe widths
- full-site editing
- theme.json
- zero custom css
- fse native
- design tokens
- style variations
- block styles
- atmosphere layer
- fluid type
- pattern library
- child theme ready
- prose-safe widths
- full-site editing
- theme.json
- zero custom css
The architecture
Everything in theme.json. Nothing hardcoded.
Every color, type step, spacing value, radius, and shadow is a token — defined once in theme.json, inherited by every block automatically. Changing your brand color is a one-line edit. Style variations replace the entire palette wholesale, so the theme supports multiple brands without a single line of custom CSS.
Color tokens
21 palette slugs covering the full tonal range: primary, accent, secondary, cool, ink, ink-soft, surface, base, border, muted, on-dark, on-dark-soft, glow, and eight more. Two gradient presets (hero-deep, brand-flow) for dark sections and CTA bands. Every preset class — has-primary-color, has-surface-background-color, etc. — works automatically.
Type, spacing, and custom tokens
A fluid type scale from eyebrow through display, with h1–h4 slugs for content headings. A spacing scale from 10 through 90 for consistent rhythm. Custom tokens for prose measure (narrow 640 px, hero 1000 px, CTA 680 px), border radius (sm, md, lg, panel), letter-spacing, and color-mix()-derived glow values.
Block styles
Section schemes, card lift, and button variants — opt-in, editor-native.
Block styles registered in functions.php, CSS in assets/styles.css. Apply them in the block editor’s styles sidebar. Nothing to memorize, nothing to add to a custom CSS field.
jxb-light · jxb-soft · jxb-dark · jxb-brand
Group: color schemes
Four section backgrounds that span the tonal range. jxb-light (white), jxb-soft (surface), jxb-dark (ink), jxb-brand (primary). Mix them down a page to create visual rhythm without writing CSS.
jxb-lift
Group: jxb-lift
A card hover treatment — subtle Y-translate and a token-driven glow on the border. Opt-in on any Group block. Used on every card grid in the plugin suite pages. CSS-only, no JavaScript.
jxb-gradient · jxb-secondary
Buttons
jxb-gradient fills the button with the brand gradient — the primary CTA style. jxb-secondary uses accent-dark fill with ink text — the second tier in a two-button pair. Convention: one primary per section.
Layout
Prose stays readable. Sections go full-bleed. Always.
contentSize is 1140 px — a layout container for grids and navigation, not a prose measure. Text self-protects. alignfull reaches the viewport. You never need to nest a constrained layout inside another constrained layout to get readable paragraphs next to wide images.
Container widths
contentSize 1140 px — layout container (grids, nav, unmarked blocks).
wideSize 1280 px — wide-aligned blocks.
alignfull — reaches the viewport edge; used for section bands.
Prose self-caps at 640 px inside post-content and centers automatically.
Named measure classes
jxb-measure-narrow — 640 px, centered; hero intros and prose sections.
jxb-measure-hero — 1000 px; large centered headline blocks.
jxb-measure-cta — 680 px; CTA band copy.
jxb-section-head — 640 px, pinned left; section intros above wide card grids.
Style variations
Swap the whole look in one click.
A variation’s palette array replaces the theme palette wholesale — all 21 slugs plus both gradients. Every preset class and every has-*-color utility updates automatically. No child theme required.
Default
Brand teal primary, neutral surfaces, high-contrast ink. The palette Jexii.com runs on. Designed for content-heavy sites that need a professional, trustworthy feel without the visual noise of a generic business theme.
Warm Editorial
Amber primary, warm off-white surfaces, slightly desaturated text. Built for publications, travel sites, and lifestyle brands where warmth and readability matter more than technical precision.
Graphite
Near-black surfaces, high-contrast accent, minimal decoration. For portfolio sites, agencies, and dark-mode-first experiences that want to feel premium without the flash.
Additional variations ship with minor releases. All variations are free.
Atmosphere
A grid, a grain, and a glow.
The atmosphere layer adds three optional effects that make a site feel considered without requiring a designer. Each effect is CSS-only and token-driven — it follows your primary color, not a hardcoded value.
Blueprint grid
A subtle line grid overlays the page — lines pick up the primary color at low opacity. Adds structure to open sections without competing with content. Disappears entirely on print.
Film grain
A fine noise texture over the background. Imperceptible on most monitors, but eliminates the “flat digital” feeling that plagues brand-kit sites. Rendered in CSS; zero network cost.
Animated glow
A slow-breathing ambient glow behind key headings, tied to the primary token. Works with dark section bands (jxb-dark, jxb-brand) and the hero gradient. Respects prefers-reduced-motion.
Enable per site
wp option update jexii_builder_atmosphere 1Or filter: jexii_builder_enable_atmosphere — return true to enable programmatically.
Who it’s for
Built for real content sites. Adopted by everyone who builds them.
WordPress developers
One set of design tokens, one set of block styles, zero custom CSS per client. Brand the theme with a style variation or child theme — the chassis stays the same. Hand off to clients with confidence that the block editor won’t break anything.
Site owners
Full-site editing the way it was meant to work — no page builder, no premium plugin required. Your header, footer, and page templates live in wp-admin under Appearance → Editor. Jexii Builder puts everything where WordPress intended it.
Jexii plugin users
The Jexii plugin suite is built and tested on Jexii Builder. Schema metaboxes, the Dashboard health panel, HUD block patterns, and jxb-* block styles are designed for this theme’s token system. Install the suite, install the theme, and it all works.
Coming soon
Free on WordPress.org.
Jexii Builder is open source and will be listed in the WordPress theme directory. This site runs on it — browse around to see it in production.
Free to use · GPL licensed · No premium tier