diff --git a/src/parse-atrule-prelude.test.ts b/src/parse-atrule-prelude.test.ts
index e25888f..e401d9c 100644
--- a/src/parse-atrule-prelude.test.ts
+++ b/src/parse-atrule-prelude.test.ts
@@ -13,6 +13,7 @@ import {
 	IDENTIFIER,
 	PRELUDE_OPERATOR,
 	URL,
+	FUNCTION,
 } from './arena'
 
 describe('At-Rule Prelude Nodes', () => {
@@ -498,10 +499,74 @@ describe('At-Rule Prelude Nodes', () => {
 
 				expect(children[0].type).toBe(CONTAINER_QUERY)
 
-				const queryChildren = children[0].children
+				const [ident, media_feature] = children[0].children
 				// Should have name and feature
-				expect(queryChildren.some((c) => c.type === IDENTIFIER)).toBe(true)
-				expect(queryChildren.some((c) => c.type === MEDIA_FEATURE)).toBe(true)
+				expect(ident.type).toBe(IDENTIFIER)
+				expect(media_feature.type).toBe(MEDIA_FEATURE)
+			})
+
+			it('should parse style container query', () => {
+				const css = '@container style(--custom: 1) { }'
+				const ast = parse(css)
+				const atRule = ast.first_child
+				const children = atRule?.children || []
+
+				expect(children[0].type).toBe(CONTAINER_QUERY)
+
+				const [fn] = children[0].children
+				expect(fn.type_name).toBe('Function')
+				expect(fn.text).toBe('style(--custom: 1)')
+				expect(fn.value).toBe('--custom: 1')
+			})
+
+			it('should parse named style container query', () => {
+				const css = '@container mytest style(--custom: 1) { }'
+				const ast = parse(css)
+				const atRule = ast.first_child
+				const children = atRule?.children || []
+
+				expect(children[0].type).toBe(CONTAINER_QUERY)
+
+				const [ident, fn] = children[0].children
+				expect(ident.type_name).toBe('Identifier')
+				expect(ident.text).toBe('mytest')
+				expect(fn.type_name).toBe('Function')
+				expect(fn.text).toBe('style(--custom: 1)')
+				expect(fn.value).toBe('--custom: 1')
+			})
+
+			it('should handle a very complex container query', () => {
+				const css = `@container style(--themeBackground),
+						not style(background-color: red),
+						style(color: green) and style(background-color: transparent),
+						style(--themeColor: blue) or style(--themeColor: purple) {
+					/* <stylesheet> */
+				}`
+				const ast = parse(css)
+				const atRule = ast.first_child
+				const children = atRule?.children || []
+				expect(children[0].type).toBe(CONTAINER_QUERY)
+
+				const container = children[0]
+				const [style1, not1, style2, style3, and, style4, style5, or, style6] = container.children
+				expect(style1.type_name).toBe('Function')
+				expect(style1.name).toBe('style')
+				expect(not1.type_name).toBe('Operator')
+				expect(not1.text).toBe('not')
+				expect(style2.type_name).toBe('Function')
+				expect(style2.name).toBe('style')
+				expect(style3.type_name).toBe('Function')
+				expect(style3.name).toBe('style')
+				expect(and.type_name).toBe('Operator')
+				expect(and.text).toBe('and')
+				expect(style4.type_name).toBe('Function')
+				expect(style4.name).toBe('style')
+				expect(style5.type_name).toBe('Function')
+				expect(style5.name).toBe('style')
+				expect(or.type_name).toBe('Operator')
+				expect(or.text).toBe('or')
+				expect(style6.type_name).toBe('Function')
+				expect(style6.name).toBe('style')
 			})
 		})
 
diff --git a/src/parse-atrule-prelude.ts b/src/parse-atrule-prelude.ts
index 2440330..5bc943f 100644
--- a/src/parse-atrule-prelude.ts
+++ b/src/parse-atrule-prelude.ts
@@ -11,6 +11,7 @@ import {
 	IDENTIFIER,
 	PRELUDE_OPERATOR,
 	URL,
+	FUNCTION,
 } from './arena'
 import {
 	TOKEN_IDENT,
@@ -244,6 +245,46 @@ export class AtRulePreludeParser {
 					components.push(feature)
 				}
 			}
+			// Function: style(--custom: 1)
+			else if (token_type === TOKEN_FUNCTION) {
+				let func_name = this.source.substring(this.lexer.token_start, this.lexer.token_end - 1) // -1 to exclude '('
+
+				// For now, treat all functions (like style()) as FUNCTION nodes
+				let func_start = this.lexer.token_start
+				let content_start = this.lexer.token_end // After '('
+
+				// Find matching closing paren
+				let paren_depth = 1
+				let func_end = this.lexer.token_end
+				let content_end = content_start
+
+				while (this.lexer.pos < this.prelude_end && paren_depth > 0) {
+					this.next_token()
+					let inner_token = this.lexer.token_type
+					if (inner_token === TOKEN_LEFT_PAREN || inner_token === TOKEN_FUNCTION) {
+						paren_depth++
+					} else if (inner_token === TOKEN_RIGHT_PAREN) {
+						paren_depth--
+						if (paren_depth === 0) {
+							content_end = this.lexer.token_start
+							func_end = this.lexer.token_end
+						}
+					} else if (inner_token === TOKEN_EOF) {
+						break
+					}
+				}
+
+				// Create function node
+				let func_node = this.create_node(FUNCTION, func_start, func_end)
+				// Set content fields to function name
+				this.arena.set_content_start_delta(func_node, 0)
+				this.arena.set_content_length(func_node, func_name.length)
+				// Set value fields to content inside parentheses
+				this.arena.set_value_start_delta(func_node, content_start - func_start)
+				this.arena.set_value_length(func_node, content_end - content_start)
+
+				components.push(func_node)
+			}
 			// Identifier: operator (and, or, not) or container name
 			else if (token_type === TOKEN_IDENT) {
 				let text = this.source.substring(this.lexer.token_start, this.lexer.token_end)