| Unsupported properties | 🔴 Critical | float, clear, z-index, transform, @keyframes, animation, pseudo-elements |
| Unsupported functions | 🔴 Critical | clamp(), min(), max() — calc() with +/- IS supported |
| Unsupported units | 🔴 Critical | fr — px, %, rem, em, vw, vh, vmin, vmax all work |
| Unsupported display | 🔴 Critical | inline, inline-flex, inline-block — only flex, grid, block, none |
| Unsupported selectors | 🔴 Critical | Attribute selectors, ::before/::after, :is(), :where() — :nth-child, :not(), :first-child, :last-child, siblings +/~ ARE supported |
| Layout in hover/active | 🔴 Critical | width, height, padding, margin, flex-*, gap in :hover/:active — IGNORED |
| Non-animatable transition | 🔴 Critical | transition targeting anything other than background-color, color, border-color, opacity |
| Extension interpolation | 🔴 Critical | --text-align-v: $var instead of --text-align-v: #{$var} |
| Per-side border colors | 🟡 Warning | border-top-color etc. — only uniform border-color works |
| Radial/conic gradient | 🔴 Critical | Only linear-gradient() supported |
| Multiple box-shadows | 🟡 Warning | Only single box-shadow per element |
| Unsupported position | 🟡 Warning | fixed, sticky — only relative and absolute |
| Missing root layout | 🟡 Warning | .root should have width: 100%; height: 100% |
| Inheritance assumptions | 🟢 Info | Only color, font-size, text-align inherit. Everything else explicit. |
| Font-family usage | 🟡 Warning | font-family in CSS is ignored — use YAML font: attribute |
| Unused CSS classes | 🟢 Info | .classname rules not referenced by any YAML style:/class: |