MATLAB uihtml Design Skill

Generate production-grade HTML/CSS/JS control panels for MATLAB uihtml components with distinctive, configurable visual styles.

When to Use

• User wants beautiful custom controls in a MATLAB app via uihtml
• User asks for a specific design style (Clean, Material, dark theme, etc.)
• User wants to redesign or restyle existing uihtml controls
• User describes a custom aesthetic for their MATLAB app controls

Style Selection

Built-in styles are documented in references/design-styles.md. To apply a style:

1. If the user names a built-in style, read the corresponding file from references/styles/<name>.md

2. If the user describes a custom aesthetic, apply creative design thinking (see below) without loading a reference style

3. If no style is specified, open the visual style gallery in the user's browser so they can see all 8 styles side-by-side:

   start "" "<skill-directory>/assets/style-gallery.html"   # Windows
   open "<skill-directory>/assets/style-gallery.html"       # macOS
   

   Then ask: "I've opened the style gallery in your browser. Which style would you like? You can also describe a custom aesthetic."

   The gallery shows interactive previews of all 8 built-in styles with a Dark/Light toggle. The available styles are:

   Style	Vibe
   Clean	Frosted glass, depth layers, spring animations
   Material	Tonal surfaces, elevation, rounded shapes
   Cosmic Dark	Deep space, neon glow, glassmorphism
   Neumorphic Dark	Embossed/debossed, soft shadow pairs
   Dashboard Light	White cards, indigo accent, data-dense
   Midnight Gradient	Blue-to-purple gradients, luxury glow
   Minimal Mono	Ultra-flat, pill buttons, single accent
   Warm Dark	Amber/yellow accent, friendly, smart home

   If the user says "just pick one" or wants to move fast, default to Clean.

Each style reference follows the 9-section DESIGN.md format and provides complete specifications for colors, typography, components, motion, and guardrails.

Design Thinking

Before generating code, commit to a clear aesthetic direction:

• Purpose: What does this control panel do? Who uses it?
• Tone: What feeling should the interface evoke?
• Constraints: Container size, MATLAB integration requirements, offline (no CDN)
• Differentiation: What makes this memorable and cohesive?

Execute the chosen direction with precision. Bold maximalism and refined minimalism both work, as long as the choice is intentional.

Workflow

1. Style selection: Identify or create the aesthetic direction
2. Component planning: Determine which controls are needed (sliders, buttons, toggles, etc.)
3. HTML generation: Produce self-contained HTML with the chosen style applied
4. MATLAB integration: Include setup(htmlComponent) boilerplate; defer full MATLAB-side wiring to the matlab-uihtml-app-builder skill

Component Library (v1)

Sliders

• Range inputs with custom thumb and track styling
• Value display with formatted units
• Horizontal layout with label + value header

Buttons

• Primary/Filled: Bold accent color, prominent shadow/glow
• Secondary/Outlined: Transparent with border, subtle hover
• Destructive/Danger: Warning color for stop/reset actions
• State: default, hover, active (scale 0.97), disabled

Toggles

• Sliding toggle switches
• On/off states with color transition
• Accessible click/tap targets

Theme System

All styles use CSS custom properties for theming. The base architecture:

:root {
    /* Semantic colors, filled by chosen style */
    --color-bg-primary: ...;
    --color-bg-secondary: ...;
    --color-bg-surface: ...;
    --color-accent: ...;
    --color-accent-hover: ...;
    --color-text-primary: ...;
    --color-text-secondary: ...;
    --color-border: ...;

    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;

    /* Typography */
    --font-family: ...;
    --font-size-sm: ...;
    --font-size-md: ...;
    --font-size-lg: ...;

    /* Radii & Shadows */
    --radius-sm: ...;
    --radius-md: ...;
    --shadow-sm: ...;
    --shadow-md: ...;

    /* Motion */
    --transition-fast: ...;
    --transition-med: ...;
}

Support both light and dark modes via prefers-color-scheme media query or a data-theme attribute on <html>:

@media (prefers-color-scheme: dark) { ... }
/* or */
[data-theme="dark"] { ... }

Container-Aware Spacing

uihtml containers in MATLAB apps are often height-constrained (e.g., a narrow side panel). When applying any style:

• Read the existing HTML first to understand how many controls need to fit
• Prioritize fitting all controls over matching the style's ideal spacing. Reduce padding, gaps, and font sizes as needed; the neumorphic effect still works at 16px padding and 16px gaps
• Use compact variants when the container holds more than 2 panels: body padding 14px, panel padding 16px, inter-panel gap 16px, button padding 9px 18px
• Never let content overflow: if overflow: hidden is set on the body, clipped controls are invisible and unusable
• Test mentally: count the vertical space budget (panels × padding + gaps + content height) and ensure it fits within a typical side-panel height (~400–500px)

Scrollable Panels (When Content Exceeds the Container)

When the control set genuinely can't be compacted further (4+ panels, mixed sliders + toggles + buttons), make the panel container scroll instead of clipping. Keep body non-scrolling so the background gradient stays anchored, and let the inner .app (or whatever you named the flex column) scroll:

html, body {
    overflow: hidden;   /* body never scrolls; background gradient stays put */
}

.app {
    height: 100%;
    overflow-y: auto;
    overflow-x: hidden;
    scrollbar-width: thin;                                    /* Firefox */
    scrollbar-color: rgba(255, 255, 255, 0.12) transparent;   /* Firefox */
}

/* Chromium (uihtml uses CEF/Chromium) */
.app::-webkit-scrollbar { width: 6px; }
.app::-webkit-scrollbar-track { background: transparent; }
.app::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.10);
    border-radius: 3px;
    transition: background var(--t-fast);
}
.app::-webkit-scrollbar-thumb:hover { background: var(--accent-glow); }

Adapt the colors to the chosen palette:

Keep the scrollbar 6px wide and the thumb under 20% alpha; anything heavier breaks the style. Don't show track borders or arrows.

Conventions

• Self-contained: No external CDN links; all CSS and JS inline in a single HTML file
• Responsive: Must work within arbitrary uihtml container sizes; use flexbox/grid with relative units
• MATLAB event boilerplate: Always include the setup(htmlComponent) function pattern:

function setup(htmlComponent) {
    window.htmlComponent = htmlComponent;

    // Listen for events from MATLAB
    htmlComponent.addEventListener("EventName", function(event) {
        // Handle event.Data
    });

    // Send events to MATLAB
    htmlComponent.sendEventToMATLAB("EventName", { key: value });
}

• Theme sync with MATLAB desktop: All templates listen for a SetTheme event. The MATLAB side can detect the desktop theme and push it to the HTML component. The settings path is R2025a+, so wrap it in try/catch with a sensible default so the app still works on older releases:

% Detect MATLAB desktop theme (R2025a+); fall back to a default on older releases
themeStr = 'dark';   % or 'light', whichever the style