name: Tailwind CSS description: Write Tailwind utility classes with proper responsive design, dark mode, and configuration. metadata: {"clawdbot":{"emoji":"🌊","requires":{"bins":["npx"]},"os":["linux","darwin","win32"]}}

Content Configuration

content array in tailwind.config.js must include ALL files with classes—missing paths = missing styles in production
Glob patterns: "./src/**/*.{js,jsx,ts,tsx,html}" covers nested directories
Dynamic class names like bg-${color}-500 won't be detected—use complete class names or safelist
Check production build size—if unexpectedly small, content paths are wrong

Mobile-first: unprefixed styles apply to all sizes, md: applies at medium AND above
sm:hidden md:block means hidden on small, visible on medium+—not "only on medium"
Breakpoints: sm(640px), md(768px), lg(1024px), xl(1280px), 2xl(1536px)
Custom breakpoints in config override defaults—use extend.screens to add without replacing

dark: prefix requires darkMode: 'class' in config—won't work with default media strategy if you need manual toggle
Dark class on <html> or <body>, not on individual components
dark:bg-gray-900 only applies when ancestor has class="dark"
System preference: darkMode: 'media' uses prefers-color-scheme

hover:, focus:, active: work as expected
group-hover: requires group class on parent—child reacts to parent hover
peer-focus: requires peer class on sibling AND sibling must come first in DOM
Stack variants: dark:hover:bg-gray-700 applies on hover in dark mode

@apply in component CSS loses responsive/state variants—@apply hover:bg-blue-500 doesn't work as expected
Order in @apply matters unlike HTML classes—later utilities override earlier
Prefer HTML classes over @apply—easier to maintain, better tree-shaking
If you must use @apply, keep it simple: base styles only

extend adds to defaults: extend: { colors: { brand: '#xxx' } } keeps all existing colors
Top-level replaces defaults: colors: { brand: '#xxx' } removes all default colors
theme() function in CSS: border-color: theme('colors.gray.200')
Plugin order matters—later plugins can override earlier ones

! prefix forces important: !mt-4 generates margin-top: 1rem !important
Use sparingly—usually indicates specificity battle that should be fixed
important: true in config makes ALL utilities important—avoid, breaks third-party CSS
important: '#app' scopes specificity to selector—better than global important

class="px-4 px-6" last one wins in stylesheet, not in HTML—both get applied, cascade decides
Forgetting overflow-hidden with rounded-* on parent with absolute children
h-screen doesn't account for mobile browser chrome—use h-dvh (dynamic viewport height)
truncate needs width constraint or max-w-* to actually truncate