Divi 5 Compatibility Reference

Quick Compatibility Check

When reviewing CSS for Divi 5, check for these issues:

CRITICAL: Not Supported

Feature	Status	Fix
ch unit	NOT SUPPORTED	Use rem (75ch -> 60rem)
ex unit	NOT SUPPORTED	Use em or rem
Container Queries	NOT YET	Coming in future update
@container	NOT YET	Use media queries

Supported Features

Feature	Status	Notes
CSS Variables	SUPPORTED	Must be in :root for global scope
calc()	SUPPORTED	Full support
clamp()	SUPPORTED	Full support
min()	SUPPORTED	Full support
max()	SUPPORTED	Full support
Flexbox	SUPPORTED	Native to Divi 5 layout
CSS Grid	SUPPORTED	Full support
px	SUPPORTED	Standard unit
em	SUPPORTED	Relative to parent font
rem	SUPPORTED	Relative to root font
%	SUPPORTED	Percentage
vw	SUPPORTED	Viewport width
vh	SUPPORTED	Viewport height
vmin	SUPPORTED	Viewport minimum
vmax	SUPPORTED	Viewport maximum

Validation Rules

Rule 1: Character Units

/* INVALID - ch not supported */
max-width: 75ch;
width: 60ch;

/* VALID - use rem instead */
max-width: 60rem;  /* 75ch -> 60rem */
width: 48rem;      /* 60ch -> 48rem */

Conversion formula: 1ch -> approx. 0.8rem (varies by font)

Rule 2: Button Specificity

/* WILL NOT WORK - Divi overrides this */
.et_pb_button {
  background-color: #000000;
}

/* WILL WORK - proper override */
body .et_pb_button {
  background-color: #000000 !important;
}

Required for buttons:

• body prefix for specificity
• !important on all properties

Rule 3: CSS Variable Scope

/* WILL NOT WORK - wrong scope */
.my-section {
  --my-color: #2ea3f2;
}
.other-element {
  color: var(--my-color);  /* Undefined! */
}

/* WILL WORK - :root scope */
:root {
  --my-color: #2ea3f2;
}
.other-element {
  color: var(--my-color);  /* Works! */
}

Rule 4: Code Module Wrapping

<!-- INVALID - raw CSS in Code Module -->
.my-class { color: red; }

<!-- VALID - wrapped in style tags -->
<style>
.my-class { color: red; }
</style>

Rule 5: Theme Options Format

/* VALID for Theme Options - no tags */
:root {
  --my-color: #2ea3f2;
}
body .et_pb_button {
  background-color: var(--my-color) !important;
}

<!-- INVALID for Theme Options - has tags -->
<style>
:root { --my-color: #2ea3f2; }
</style>

Common Issues & Fixes

Issue: Button styles not applying

Symptom: Custom button colors/styles ignored Cause: Low specificity, missing !important Fix:

body .et_pb_button {
  background-color: #000000 !important;
  border-radius: 0 !important;
  /* ALL properties need !important */
}

Issue: Text too wide on large screens

Symptom: Text stretches across entire screen Cause: Using ch unit or no max-width Fix:

.et_pb_text_inner p {
  max-width: 60rem;  /* NOT 75ch */
}

Issue: CSS Variables not working

Symptom: Variables undefined or not applying Cause: Wrong scope or wrong syntax Fix:

/* Variables MUST be in :root */
:root {
  --my-color: #2ea3f2;
}

/* Reference with var() */
.element {
  color: var(--my-color);
}

Issue: Hover states not working

Symptom: Hover effects ignored Cause: Divi's inline styles override Fix:

body .et_pb_button:hover {
  background-color: #222222 !important;
  /* Include ALL hover properties */
}

Issue: Font not loading

Symptom: Fallback font displays instead Cause: Font not loaded or wrong name Fix:

/* Ensure font is loaded via Google Fonts or @font-face */
/* Use exact font name with proper fallbacks */
font-family: 'Fira Sans', system-ui, sans-serif !important;

Issue: Section background wrong

Symptom: Background color different than expected Cause: Divi's inline styles Fix:

.et_pb_section.my-dark-section {
  background-color: #1d1f22 !important;
}

Issue: Flexbox layout breaking

Symptom: Layout doesn't match design Cause: Divi 5 uses Flexbox by default, conflicts with custom Fix: Work with Divi's Flexbox, don't fight it

/* Use Divi's built-in flex controls in Visual Builder */
/* Or override completely */
.et_pb_row {
  display: flex !important;
  flex-direction: row !important;
  gap: 2rem !important;
}

Validation Checklist

When reviewing CSS for Divi 5, verify:

• No ch or ex units
• No @container queries
• All button overrides have body prefix and !important
• CSS Variables defined in :root
• Code Module CSS wrapped in <style> tags
• Theme Options CSS has NO <style> tags
• Hover states include !important
• Font families include fallbacks
• Max-width uses rem not ch

Error Messages Reference

"Property ignored"

Usually means low specificity. Add !important.

"Unknown property"

Check for typos or unsupported properties.

"Unknown unit"

Using ch or ex. Replace with rem or em.

"Unexpected token"

Syntax error. Check for missing semicolons, braces, or quotes.

Styles not applying at all

Check:

1. Is CSS in correct location? (Theme Options vs Code Module)
2. Are style tags correct? (needed for Code Module, NOT for Theme Options)
3. Is selector correct? Check in browser DevTools

Divi-Specific CSS Debugging

Using Browser DevTools

1. Right-click element -> Inspect
2. Look at Styles panel
3. Check for:
   • Crossed-out styles (being overridden)
   • Grayed-out styles (invalid)
   • Inline styles (Divi's defaults)

Common Override Pattern

/* If Divi uses: */
style="background-color: blue !important;"

/* You need higher specificity: */
body .et_pb_section#my-id {
  background-color: red !important;
}
/* Or use ID selector for highest specificity */

Compatibility Mode Reference

Advisory Mode (Default)

• Reports issues as warnings
• Suggests fixes
• Allows proceeding with warnings

Strict Mode

• Reports issues as errors
• Requires fixes before proceeding
• Blocks incompatible CSS

Configure in .claude/divi5-toolkit.local.md:

---
validation_mode: advisory  # or "strict"
---

Resources

When issues aren't resolved:

1. Check Elegant Themes documentation: https://help.elegantthemes.com
2. Research on Context7 for latest Divi 5 updates
3. Use /divi5-toolkit:research command for current info
4. Consult Codex or ChatGPT for complex CSS questions