fix: preserve whitespace between media keywords and opening parenthesis

CSS media query keywords (and, or, not, only) must be separated from
adjacent parentheses by whitespace. Without a space, `and(condition)` is
parsed as a function call rather than the keyword followed by a
media condition, making the at-rule invalid.

Add a replaceAll pass to insert the required space whenever one of
these keywords is directly followed by `(`, and expand test coverage
to include `@media all and screen {}` and related keyword combinator
patterns.

https://claude.ai/code/session_01FnNEbE8DRPAFamgWRW4B7L

Author: claude

src/lib/index.ts

@@ -303,6 +303,7 @@ export function format_atrule_prelude(
 	return prelude
 		.replaceAll(/\s*([:,])/g, prelude.toLowerCase().includes('selector(') ? '$1' : '$1 ') // force whitespace after colon or comma, except inside `selector()`
 		.replaceAll(/\)([a-zA-Z])/g, ') $1') // force whitespace between closing parenthesis and following text (usually and|or)
+		.replaceAll(/\b(and|or|not|only)\(/gi, '$1 (') // force whitespace between media/supports keywords and opening parenthesis
 		.replaceAll(/\s*(=>|>=|<=)\s*/g, `${optional_space}$1${optional_space}`) // add optional spacing around =>, >= and <=
 		.replaceAll(/([^<>=\s])([<>])([^<>=\s])/g, `$1${optional_space}$2${optional_space}$3`) // add spacing around < or > except when it's part of <=, >=, =>
 		.replaceAll(/([^<>=\s])\s+([<>])\s+([^<>=\s])/g, `$1${optional_space}$2${optional_space}$3`) // handle spaces around < or > when they already have surrounding whitespace

test/api.test.ts

@@ -103,7 +103,20 @@ describe('format_atrule_prelude', () => {
 	})
 
 	test('adds space between ) and following word', () => {
-		expect(format_atrule_prelude('(width > 0)and(height > 0)')).toBe('(width > 0) and(height > 0)')
+		expect(format_atrule_prelude('(width > 0)and(height > 0)')).toBe('(width > 0) and (height > 0)')
+	})
+
+	test('adds space between media keyword "and" and opening parenthesis', () => {
+		expect(format_atrule_prelude('(width > 0)and(height > 0)', { minify: true })).toBe('(width>0) and (height>0)')
+	})
+
+	test('adds space between media keyword "not" and opening parenthesis', () => {
+		expect(format_atrule_prelude('not(color)')).toBe('not (color)')
+		expect(format_atrule_prelude('not(color)', { minify: true })).toBe('not (color)')
+	})
+
+	test('adds space between media keyword "or" and opening parenthesis', () => {
+		expect(format_atrule_prelude('(width > 0)or(height > 0)')).toBe('(width > 0) or (height > 0)')
 	})
 
 	test('lowercases function names', () => {

test/atrules.test.ts

@@ -373,6 +373,48 @@ test('minify: keeps necessary whitespace between keywords', () => {
 	expect(actual).toEqual(expected)
 })
 
+test('minify: keeps necessary whitespace in @media all and screen', () => {
+	let actual = minify(`@media all and screen {}`)
+	let expected = `@media all and screen{}`
+	expect(actual).toEqual(expected)
+})
+
+test('minify: keeps whitespace between "and" keyword and following media feature', () => {
+	let actual = minify(`@media screen and (min-width: 100px) {}`)
+	let expected = `@media screen and (min-width:100px){}`
+	expect(actual).toEqual(expected)
+})
+
+test('minify: keeps whitespace between "and" keywords with adjacent media features', () => {
+	let actual = minify(`@media (min-width: 100px) and (max-width: 200px) {}`)
+	let expected = `@media (min-width:100px) and (max-width:200px){}`
+	expect(actual).toEqual(expected)
+})
+
+test('minify: keeps whitespace between "not" keyword and media feature', () => {
+	let actual = minify(`@media not (color) {}`)
+	let expected = `@media not (color){}`
+	expect(actual).toEqual(expected)
+})
+
+test('minify: keeps whitespace between "not" keyword and media type', () => {
+	let actual = minify(`@media not screen {}`)
+	let expected = `@media not screen{}`
+	expect(actual).toEqual(expected)
+})
+
+test('minify: keeps whitespace between "only" keyword and media type', () => {
+	let actual = minify(`@media only screen {}`)
+	let expected = `@media only screen{}`
+	expect(actual).toEqual(expected)
+})
+
+test('minify: keeps whitespace between "or" keyword and media feature', () => {
+	let actual = minify(`@media (min-width: 100px) or (max-width: 200px) {}`)
+	let expected = `@media (min-width:100px) or (max-width:200px){}`
+	expect(actual).toEqual(expected)
+})
+
 // oxlint-disable-next-line vitest/no-disabled-tests
 test.skip('preserves comments', () => {
 	let actual = format(`