This is a generated navigation projection. Choose the relevant decision module first; use this table to verify the browser-floor and fallback constraint.
| Capability | Fallback | Evidence |
|---|---|---|
| Aspect Ratio | Explicit dimensions only where content remains usable. | MDN aspect-ratio MDN Baseline compatibility |
| Cascade Layers | Intentional source order. | MDN @layer MDN Baseline compatibility |
| Clamp | The min value. | MDN clamp() MDN Baseline compatibility |
| Color Mix | Precomputed derived color token. | MDN color-mix() MDN Baseline compatibility |
| Container Queries | Intrinsic wrapping or a viewport query for page-level behavior. | MDN container queries MDN Baseline compatibility |
| Container Units | rem and clamp values. | MDN container query length units MDN Baseline compatibility |
| Content Visibility | Normal rendering. | MDN content-visibility MDN contain-intrinsic-size MDN Baseline compatibility |
| Custom Properties | Literal default declarations are available, but semantic custom properties are the preferred interface. | MDN CSS custom properties MDN Baseline compatibility |
| Dynamic Viewport Units | min-block-size with normal document flow. | MDN viewport length units MDN Baseline compatibility |
| Flexbox | Block flow. | MDN flex alignment MDN Baseline compatibility |
| Focus Visible | :focus indicator. | MDN :focus-visible MDN Baseline compatibility |
| Forced Colors | Permit user-agent color mapping. | MDN forced-colors MDN system colors MDN Baseline compatibility |
| Grid | Block flow or Flexbox. | MDN CSS Grid Layout MDN Baseline compatibility |
| Has | Owner-managed class or data state. | MDN :has() MDN Baseline compatibility |
| Logical Properties | Physical properties for a constrained legacy direction policy. | MDN logical properties MDN Baseline compatibility |
| Native Nesting | Flat selectors or a preprocessor in an existing project. | MDN CSS nesting MDN Baseline compatibility |
| Oklch | Precomputed sRGB semantic colors. | MDN oklch() MDN Baseline compatibility |
| Prefers Contrast | WCAG-conformant normal theme. | MDN prefers-contrast MDN Baseline compatibility |
| Property | Untyped custom property or ordinary property transition. | MDN @property MDN Baseline compatibility |
| Reduced Motion | Low-motion default. | MDN prefers-reduced-motion MDN Baseline compatibility |
| Size Adjust | Normal fallback font metrics. | MDN size-adjust MDN Baseline compatibility |
| Subgrid | Explicit local tracks. | MDN subgrid MDN Baseline compatibility |
| User Valid | Native validity UI and explicit messages. | MDN :user-valid MDN :user-invalid MDN Baseline compatibility |
| Capability | Fallback | Evidence |
|---|---|---|
| Anchor Positioning | Conventional positioned layout or Popover API. | MDN CSS anchor positioning MDN Baseline compatibility |
| Container Style Queries | Explicit data or variant class. | MDN @container web.dev platform updates May 2026 |
| Contrast Color | A verified authored foreground token. | MDN contrast-color() MDN Baseline compatibility |
| Custom Highlights | Normal browser selection/find rendering. | MDN ::highlight() MDN Baseline compatibility |
| Field Sizing | Explicit logical sizes. | MDN field-sizing MDN Baseline compatibility |
| Light Dark | prefers-color-scheme token overrides. | MDN light-dark() MDN Baseline compatibility |
| Name Only Container Queries | Explicit data or variant class. | MDN @container web.dev platform updates May 2026 |
| Open | Attribute selector or owner state class. | MDN :open web.dev platform updates May 2026 |
| Popover | Inline content or an accessible dialog. | MDN :popover-open MDN Baseline compatibility |
| Same Document View Transitions | Normal state change. | MDN view-transition-name MDN view-transition-class MDN Baseline compatibility |
| Scope | CSS Modules or a documented component root class. | MDN @scope MDN Baseline compatibility |
| Starting Style | Enter without a transition. | MDN @starting-style MDN Baseline compatibility |
| Text Box | Normal line box metrics. | MDN text-box MDN Baseline compatibility |
| Text Wrap | Normal wrapping. | MDN text-wrap MDN Baseline compatibility |
| Transition Behavior | Immediate discrete state change. | MDN transition-behavior MDN Baseline compatibility |
| Capability | Fallback | Evidence |
|---|---|---|
| Accent Color | Native control colors. | MDN accent-color MDN Baseline compatibility |
| Ascent Override | size-adjust or an ordinary fallback stack. | MDN ascent-override MDN Baseline compatibility |
| Corner Shape | border-radius. | MDN corner-shape MDN Baseline compatibility |
| Customizable Select | Native select. | MDN appearance MDN ::picker MDN Baseline compatibility |
| Interpolate Size | Grid-row or immediate disclosure. | MDN interpolate-size MDN calc-size() MDN Baseline compatibility |
| Line Clamp | Show full content or provide an explicit disclosure. | MDN line-clamp MDN Baseline compatibility |
| Media State Pseudo Classes | Owner-managed state class. | MDN :playing MDN Baseline compatibility |
| Reduced Transparency | A solid-surface default. | MDN prefers-reduced-transparency MDN Baseline compatibility |
| Relative Colors | Precomputed semantic color token. | MDN relative colors MDN Baseline compatibility |
| Round | Ordinary calc or precomputed value. | MDN round() MDN Baseline compatibility |
| Scroll Driven Animations | Static content or ordinary transition. | MDN scroll-driven animations MDN animation-timeline WebKit guide to scroll-driven animations |
| Scroll State Queries | Owner-managed state class or no effect. | MDN scroll-state container queries MDN Baseline compatibility |
| Shape | polygon(), border radius, or a static asset. | MDN shape() MDN Baseline compatibility |
| Typed Attr | A class, custom property, or ordinary attribute interpreted by the owner. | MDN attr() MDN Baseline compatibility |
| Capability | Fallback | Evidence |
|---|---|---|
| Css Functions | Custom property values calculated by the build or owner code. | MDN if() MDN @function MDN sibling-index() MDN sibling-count() |