Migration: public/styles.less → Theme YAML + CSS

Context

Lowdefy v4 supported public/styles.less for custom styling with Less variables that mapped to antd's Less-based theming. Antd v6 uses CSS-in-JS with design tokens. Less is no longer processed by the build.

What to Do

1. Check if public/styles.less exists
2. If it does, parse its content and split into two buckets:
   • Less variables → map to antd design tokens in lowdefy.yaml theme config
   • Plain CSS / complex Less → convert to public/styles.css

Known Less Variable → Token Mapping

For each variable found, generate the equivalent theme.antd.token YAML:

# Add to lowdefy.yaml
theme:
  antd:
    token:
      colorPrimary: '#1890ff'
      fontSize: 14
      borderRadius: 4

Complex Less (manual conversion needed)

Flag these for manual conversion:

• Less mixins (.mixin())
• Less functions (darken(), lighten(), fade())
• Nested selectors with &
• @import statements (other than antd imports)
• Any Less-specific syntax

Convert remaining plain CSS to public/styles.css.

Files to Check

Check: public/styles.less

Examples

Before — styles.less

@primary-color: #1890ff;
@border-radius-base: 6px;
@font-size-base: 14px;

.custom-header {
  padding: 16px;
  background: @primary-color;
}

After — lowdefy.yaml addition

theme:
  antd:
    token:
      colorPrimary: '#1890ff'
      borderRadius: 6
      fontSize: 14

After — public/styles.css (for non-variable CSS)

.custom-header {
  padding: 16px;
  background: var(--ant-color-primary);
}

Edge Cases

• If styles.less contains only variables and no custom CSS, only the lowdefy.yaml theme config is needed — no styles.css
• Less expressions like darken(@primary-color, 10%) have no direct token equivalent — flag these for manual conversion to CSS custom properties or hardcoded values
• Some apps may import antd Less files (@import '~antd/dist/antd.less') — these lines can be removed entirely (antd v6 doesn't use Less)
• If lowdefy.yaml already has a theme: section, merge the tokens into it

CRITICAL: Delete public/styles.less

After migrating, you MUST delete public/styles.less. The v5 build checks for this file and throws a fatal ConfigError if it exists — even if it's empty. The build will not proceed until the file is removed.

rm public/styles.less

Verification

1. public/styles.less must NOT exist — the build will fail if it does
2. Theme tokens are in lowdefy.yaml under theme.antd.token
3. Custom CSS (if any) is in public/styles.css
4. The app builds without Less processing errors