svg-design

SVG Creation and Editing

Core principle: SVGs are code. Write them by hand like you'd write any markup: clean, minimal, semantically meaningful. Every element and attribute should earn its place.

Topic Routing

Task	Load reference
Arc flag combinations, common path shapes	references/path-patterns.md
Logo design, typography, negative space	references/logo-techniques.md
Icon design, grid systems, pixel alignment	references/icon-design.md
Gradients, masks, clips, filters, transforms (design decisions)	references/advanced-techniques.md
Animation (CSS keyframes, stagger, GPU, easing, SVG-specific)	references/animation.md
Optimization, sprites, SVGO config	references/optimization.md
Accessibility, browser pitfalls	references/accessibility-and-pitfalls.md
Editing workflow, boolean operations, combining SVGs	references/editing-workflow.md

SVG Skeleton

Always start from this structure:

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
  <!-- content -->
</svg>

Adjust viewBox to match the design canvas. Omit width/height attributes to let the SVG scale with its container (add them only when a fixed size is needed).

Canvas Size Conventions

Size	Use case	Notes
0 0 16 16	Micro icons, favicons	Heroicons micro, GitHub Octicons
0 0 20 20	Small UI icons, form elements	Heroicons mini
0 0 24 24	Standard icons (most common)	Lucide, Heroicons outline, Material
0 0 32 32	Medium icons, navigation	Phosphor uses 256x256 internally
0 0 48 48	Large display icons	App icons, illustrations
Custom	Logos, illustrations	Match the natural aspect ratio

Default to 24x24 unless there's a reason not to. It's the industry standard.

Shape vs Path Decision

Use shape primitive when...	Use <path> when...
The shape is a basic geometric form	The shape has curves, complex outlines
Readability matters (a circle should look like <circle>)	You need to minimize element count
You need to animate individual properties (r, cx, cy)	Combining multiple shapes into one element
The shape will be programmatically modified	Exporting from design tools (paths are universal)

Styling Defaults

Set these on the root <svg> element to avoid repetition on children:

Attribute	Icon default	Logo default	Why
fill	none	varies	Icons are typically stroked, logos are filled
stroke	currentColor	none or currentColor	Inherits text color from parent
stroke-width	2 (on 24x24)	varies	Consistent weight across icons
stroke-linecap	round	round or butt	Rounded ends look cleaner at small sizes
stroke-linejoin	round	round or miter	Prevents sharp spikes at joins

currentColor is your friend. It lets the SVG inherit whatever color the parent element has, making icons themeable with zero extra CSS.

Stroke-Width Relative to ViewBox

stroke-width is in viewBox units, not pixels. Always set relative to your canvas dimensions:

viewBox	Typical stroke-width	Visual result
16x16	1.5	~9.4% of canvas
24x24	2	~8.3% of canvas
32x32	2-2.5	~6.3-7.8% of canvas
48x48	3	~6.3% of canvas
256x256	16	~6.3% of canvas

When to Convert Shapes to Paths

Convert when:

• Combining multiple shapes into a single compound path (boolean operations)
• You need the shape as part of a larger path composition
• Distributing to environments that only support <path>
• Optimizing for minimal DOM elements

Keep as shapes when:

• Code readability matters (a <circle> is self-documenting)
• You need to animate specific properties (animating r on a circle is cleaner than animating path data)
• The SVG will be programmatically modified

Rounded rect-to-path template

The arc parameters here are error-prone to derive. Use this as a reference:

<!-- <rect x="2" y="2" width="20" height="20" rx="3" /> becomes: -->
<path d="M 5 2 h 14 a 3 3 0 0 1 3 3 v 14 a 3 3 0 0 1 -3 3 h -14 a 3 3 0 0 1 -3 -3 v -14 a 3 3 0 0 1 3 -3 Z" />

fill-rule: evenodd vs nonzero

Use evenodd when you have compound shapes with holes. It's simpler because you don't need to worry about winding direction:

<!-- Donut using evenodd (direction doesn't matter) -->
<path fill-rule="evenodd" d="
  M 12 2 A 10 10 0 1 1 12 22 A 10 10 0 1 1 12 2 Z
  M 12 7 A 5 5 0 1 1 12 17 A 5 5 0 1 1 12 7 Z
" fill="black" />

With nonzero (default), the inner circle must wind in the opposite direction to create the hole.

Logo Design Process

When creating logos (not icons), follow this process:

0. Always clarify design direction before creating logos. Use AskUserQuestion to present curated design direction choices before writing any SVG code. This step is mandatory for all logo projects. Even when the user provides some direction (like "modern" or "YC style"), those are vibes, not design briefs. A designer would still present options to narrow the direction before investing in 5-15 concepts.

   Present choices like a designer showing mood boards. Don't ask open-ended questions. Tailor options to the user's domain:

   AskUserQuestion({
     questions: [
       {
         question: "What visual personality fits your brand?",
         header: "Mood",
         multiSelect: false,
         options: [
           { label: "Bold & geometric", description: "Clean shapes, strong lines, confident. Think Stripe, Figma." },
           { label: "Organic & crafted", description: "Hand-drawn feel, natural curves, warmth. Think Mailchimp, Basecamp." },
           { label: "Minimal & typographic", description: "Wordmark-driven, restrained, sophisticated. Think Glossier, Everlane." },
           { label: "Playful & dynamic", description: "Energetic, colorful, movement. Think Slack, Discord." }
         ]
       },
       {
         question: "What should the logo emphasize?",
         header: "Focus",
         multiSelect: false,
         options: [
           { label: "What we do", description: "Visual metaphor tied to your product's core function" },
           { label: "How it feels", description: "Abstract mark that conveys emotion or energy" },
           { label: "Who we are", description: "Letterform or wordmark built from the brand name" }
         ]
       },
       {
         question: "Which of these logos in your space resonates most?",
         header: "Inspiration",
         multiSelect: false,
         options: [
           // IMPORTANT: populate these with 3-4 real, well-known brands
           // in or adjacent to the user's specific industry/domain.
           // Examples below are for an AI startup - replace entirely
           // for other domains.
           { label: "Linear", description: "Precise geometric icon, purple gradient, premium feel" },
           { label: "Stripe", description: "Simple bold wordmark, single accent color, confident restraint" },
           { label: "Notion", description: "Friendly icon with personality, approachable, slightly playful" },
           { label: "Vercel", description: "Abstract minimal triangle, stark black/white, developer-focused" }
         ]
       }
     ]
   })
   

   Tailoring the questions to the domain is critical. The mood options, focus options, and especially the inspiration logos must be specific to the user's industry. A coffee brand gets Blue Bottle, Stumptown, Intelligentsia, Counter Culture as inspiration options. A fintech startup gets Stripe, Plaid, Mercury, Ramp. A fitness app gets Peloton, Strava, Nike Run Club, Whoop. Pick brands the user will immediately recognize and have an opinion about. The inspiration question does the most work here because it anchors the entire aesthetic direction to something concrete.

   The only exception: skip if the user has specified both a concrete visual style AND specific imagery (e.g., "minimalist geometric logo using a mountain silhouette in navy blue").

1. Explore multiple metaphors, not multiple layouts of one metaphor. Conceptual diversity matters more than layout variations. Follow the full ideation process in references/logo-techniques.md, which covers domain-specific brainstorming, category diversity requirements, and cliche avoidance.

2. Guarantee structural variety. Every logo set must span multiple categories of approach, not just multiple metaphors within the same style. Include at least one from each column when presenting 5+ options: a typographic/wordmark approach, a symbolic icon, an abstract geometric mark, and a letterform-meets-metaphor hybrid. See the category diversity table in references/logo-techniques.md.

3. Set up the preview immediately, then populate it progressively. Don't design all logos first and then show them. The user should see results as they're created:

   1. Copy this skill's assets/preview.html to the project directory using cp with the absolute path from where this skill was loaded (do not read or modify the file).
   2. Design the first logo and write its SVG file.
   3. Write variants.js with just that first variant (format in references/editing-workflow.md).
   4. Open the preview with open preview.html (macOS) or xdg-open preview.html (Linux). The user now sees the first logo while you keep working.
   5. For each subsequent logo: write the SVG file, then update variants.js to add it. The preview auto-reloads both every 3 seconds, so new logos appear in the browser as they're completed.

   This gives the user visual feedback within seconds of the first logo being ready, rather than waiting for all logos to be designed before seeing anything.

4. For colored logos, always create a -dark.svg variant. Dark navy edges (#1E3A5F) that look great on white disappear on dark backgrounds. Dark variants need lighter edges (#4B8BBE), lighter rings (#3B6B8A), and off-white centers (#E2E8F0).

5. Plan your vertical budget before drawing. On a 32x32 canvas with 3 stacked elements, you have ~30 usable units. Sketch the vertical distribution first (e.g., box=12, gap=2, layer=5, gap=2, layer=5) to avoid clipping at viewBox edges.

Anti-Patterns

Don't	Do instead
Hardcode width="24" height="24" without viewBox	Use viewBox always; add width/height only if needed
Set fill="none" on a <g> group	Set fill on individual elements or the root <svg>
Use px units inside SVG	SVG coordinates are unitless; they map to viewBox
Include editor metadata (<sodipodi:*>, <inkscape:*>)	Strip all editor cruft
Use <text> for logo wordmarks in distributed SVGs	Convert text to paths for portability
Nest transforms three levels deep	Flatten transforms into path coordinates
Use xlink:href	Use href (xlink is deprecated)
Forget xmlns on standalone SVG files	Always include xmlns="http://www.w3.org/2000/svg"
Use decimal precision beyond 2-3 places for icons	Round to 2 decimals for icons, 3 max for complex art

Cross-References

• Design aesthetics: If the ce plugin is installed, Skill(ce:design) covers broader visual design decisions
• Mermaid diagrams: If the ce plugin is installed, Skill(ce:visualizing-with-mermaid) covers diagram-specific visualizations (not SVG)