type-systems（类型系统）

Type Systems

Typography is a system. Every decision should be intentional and connected.

How to use

• /type-systems Apply type system constraints to this conversation.

Constraints

Scale

• MUST use a mathematical ratio for the type scale (1.25, 1.333, 1.5 between sizes)
• Wide range (12px to 72px): dramatic hierarchy, suits editorial and marketing
• Narrow range (14px to 24px): subtle hierarchy, suits dense products
• NEVER use random sizes. If it's not on the scale, it shouldn't exist.
• MUST limit to 4-6 sizes per screen maximum with clear justification for each

Weight

• 1-2 weights: discipline. Hierarchy comes from scale and space, not weight.
• 3 weights: normal range. Regular body, medium emphasis, bold headlines.
• 4+ weights: either the system demands it or you haven't made a decision.
• MUST ensure each weight serves a distinct, named purpose

Line Height

• Body text: 1.5-1.7x font size. Where readability lives.
• Headlines: 1.1-1.3x. Large text has built-in breathing room.
• UI labels: 1.2-1.4x. Compact but not crushed.
• NEVER use the same line height for all text sizes

Letter Spacing

• Body text: leave it alone. The type designer already optimized it.
• All-caps labels: add 2-5% tracking. Capitals need air.
• Large display text (72px+): sometimes benefits from tightening.

Anti-Patterns

• More than 3 type sizes on a single screen without clear hierarchy justification
• Centering paragraphs longer than 3 lines
• Lines over 75 characters wide (hurts readability)
• Inconsistent weight usage with no system behind it