Reintroduce container component as a utility

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Support opacity values in increments of `0.25` by default ([#14980](https://github.com/tailwindlabs/tailwindcss/pull/14980))
 - Support specifying the color interpolation method for gradients via modifier ([#14984](https://github.com/tailwindlabs/tailwindcss/pull/14984))
+- Add `container` utility that mimics the v3 `container` component ([#14993](https://github.com/tailwindlabs/tailwindcss/pull/14993))
 
 ### Fixed
 

packages/tailwindcss/src/__snapshots__/intellisense.test.ts.snap

@@ -3375,6 +3375,7 @@ exports[`getClassList 1`] = `
   "contain-size",
   "contain-strict",
   "contain-style",
+  "container",
   "content-around",
   "content-baseline",
   "content-between",

packages/tailwindcss/src/property-order.ts

@@ -28,6 +28,8 @@ export default [
   'float',
   'clear',
 
+  '--tw-container-component',
+
   // How do we make `mx-0` come before `mt-0`?
   // Idea: `margin-x` property that we compile away with a Visitor plugin?
   'margin',

packages/tailwindcss/src/utilities.test.ts

@@ -3148,6 +3148,168 @@ test('max-height', async () => {
   ).toEqual('')
 })
 
+describe('container', () => {
+  test('creates the right media queries and sorts it before width', async () => {
+    expect(
+      await compileCss(
+        css`
+          @theme {
+            --breakpoint-sm: 40rem;
+            --breakpoint-md: 48rem;
+            --breakpoint-lg: 64rem;
+            --breakpoint-xl: 80rem;
+            --breakpoint-2xl: 96rem;
+          }
+          @tailwind utilities;
+        `,
+        ['w-1/2', 'container', 'max-w-[var(--breakpoint-sm)]'],
+      ),
+    ).toMatchInlineSnapshot(`
+      ":root {
+        --breakpoint-sm: 40rem;
+        --breakpoint-md: 48rem;
+        --breakpoint-lg: 64rem;
+        --breakpoint-xl: 80rem;
+        --breakpoint-2xl: 96rem;
+      }
+
+      .container {
+        width: 100%;
+      }
+
+      @media (width >= 40rem) {
+        .container {
+          max-width: 40rem;
+        }
+      }
+
+      @media (width >= 48rem) {
+        .container {
+          max-width: 48rem;
+        }
+      }
+
+      @media (width >= 64rem) {
+        .container {
+          max-width: 64rem;
+        }
+      }
+
+      @media (width >= 80rem) {
+        .container {
+          max-width: 80rem;
+        }
+      }
+
+      @media (width >= 96rem) {
+        .container {
+          max-width: 96rem;
+        }
+      }
+
+      .w-1\\/2 {
+        width: 50%;
+      }
+
+      .max-w-\\[var\\(--breakpoint-sm\\)\\] {
+        max-width: var(--breakpoint-sm);
+      }"
+    `)
+  })
+
+  test('custom `@utility container` always follow the core utility ', async () => {
+    expect(
+      await compileCss(
+        css`
+          @theme {
+            --breakpoint-sm: 40rem;
+            --breakpoint-md: 48rem;
+            --breakpoint-lg: 64rem;
+            --breakpoint-xl: 80rem;
+            --breakpoint-2xl: 96rem;
+          }
+          @tailwind utilities;
+
+          @utility container {
+            margin-left: auto;
+            margin-right: auto;
+            padding-right: 2rem;
+            padding-left: 2rem;
+
+            @media (min-width: 126rem) {
+              max-width: 126rem;
+            }
+          }
+        `,
+        ['w-1/2', 'container', 'max-w-[var(--breakpoint-sm)]'],
+      ),
+    ).toMatchInlineSnapshot(`
+      ":root {
+        --breakpoint-sm: 40rem;
+        --breakpoint-md: 48rem;
+        --breakpoint-lg: 64rem;
+        --breakpoint-xl: 80rem;
+        --breakpoint-2xl: 96rem;
+      }
+
+      .container {
+        width: 100%;
+      }
+
+      @media (width >= 40rem) {
+        .container {
+          max-width: 40rem;
+        }
+      }
+
+      @media (width >= 48rem) {
+        .container {
+          max-width: 48rem;
+        }
+      }
+
+      @media (width >= 64rem) {
+        .container {
+          max-width: 64rem;
+        }
+      }
+
+      @media (width >= 80rem) {
+        .container {
+          max-width: 80rem;
+        }
+      }
+
+      @media (width >= 96rem) {
+        .container {
+          max-width: 96rem;
+        }
+      }
+
+      .container {
+        margin-left: auto;
+        margin-right: auto;
+        padding-left: 2rem;
+        padding-right: 2rem;
+      }
+
+      @media (width >= 126rem) {
+        .container {
+          max-width: 126rem;
+        }
+      }
+
+      .w-1\\/2 {
+        width: 50%;
+      }
+
+      .max-w-\\[var\\(--breakpoint-sm\\)\\] {
+        max-width: var(--breakpoint-sm);
+      }"
+    `)
+  })
+})
+
 test('flex', async () => {
   expect(
     await run([
@@ -16680,7 +16842,7 @@ describe('spacing utilities', () => {
     `)
   })
 
-  test('only multiples of 0.25 with no trailing zeroes are supported with the spacing multipler', async () => {
+  test('only multiples of 0.25 with no trailing zeroes are supported with the spacing multiplier', async () => {
     let { build } = await compile(css`
       @theme {
         --spacing: 4px;

packages/tailwindcss/src/utilities.ts

@@ -897,6 +897,18 @@ export function createUtilities(theme: Theme) {
     })
   }
 
+  utilities.static('container', () => {
+    let breakpoints = [...theme.namespace('--breakpoint').values()]
+    breakpoints.sort((a, b) => parseInt(a) - parseInt(b))
+
+    let decls: AstNode[] = [decl('--tw-sort', '--tw-container-component'), decl('width', '100%')]
+    for (let breakpoint of breakpoints) {
+      decls.push(atRule('@media', `(min-width: ${breakpoint})`, [decl('max-width', breakpoint)]))
+    }
+
+    return decls
+  })
+
   /**
    * @css `flex`
    */