feat(sbb-container): support for background image

src/elements/container/container/__snapshots__/container.snapshot.spec.snap.js

@@ -9,8 +9,12 @@ snapshots["sbb-container renders DOM"] =
 
 snapshots["sbb-container renders Shadow DOM"] = 
 `<div class="sbb-container">
-  <slot>
+  <slot name="image">
   </slot>
+  <div class="sbb-container__content">
+    <slot>
+    </slot>
+  </div>
 </div>
 <slot name="sticky-bar">
 </slot>

src/elements/container/container/container.scss

@@ -15,6 +15,10 @@
   --sbb-container-background-color: var(--sbb-color-milk);
 }
 
+:host([data-slot-names~='image']) {
+  --sbb-container-background-color: transparent;
+}
+
 :host(:not([expanded])[background-expanded]) {
   background-color: var(--sbb-container-background-color);
 }
@@ -38,4 +42,33 @@
   :host([expanded]) & {
     @include sbb.page-spacing-expanded;
   }
+
+  :host([data-slot-names~='image']) & {
+    position: relative;
+  }
+}
+
+.sbb-container__content {
+  position: relative;
+}
+
+::slotted([slot='image']) {
+  --sbb-image-border-radius: 0;
+
+  position: absolute;
+  inset: 0;
+
+  :host(:not([expanded])) & {
+    @include sbb.mq($from: ultra) {
+      --sbb-image-border-radius: var(--sbb-border-radius-4x);
+
+      border-radius: var(--sbb-border-radius-4x);
+    }
+  }
+}
+
+::slotted(img[slot='image']) {
+  object-fit: cover;
+  height: 100%;
+  width: 100%;
 }

src/elements/container/container/container.snapshot.spec.ts

@@ -11,7 +11,7 @@ describe(`sbb-container`, () => {
     let element: SbbContainerElement;
 
     beforeEach(async () => {
-      element = await fixture(html` <sbb-container></sbb-container> `);
+      element = await fixture(html`<sbb-container></sbb-container>`);
     });
 
     it('DOM', async () => {

src/elements/container/container/container.stories.ts

@@ -1,10 +1,13 @@
 import type { InputType } from '@storybook/types';
-import type { ArgTypes, Args, Meta, StoryObj } from '@storybook/web-components';
-import { type TemplateResult, html, nothing } from 'lit';
+import type { Args, ArgTypes, Meta, StoryObj } from '@storybook/web-components';
+import { html, nothing, type TemplateResult } from 'lit';
 
 import { sbbSpread } from '../../../storybook/helpers/spread.js';
+import sampleImages from '../../core/images.js';
 
 import '../../button/secondary-button.js';
+import '../../card.js';
+import '../../image.js';
 import '../../title.js';
 import './container.js';
 
@@ -19,9 +22,22 @@ const containerContent = (title: string, last = false): TemplateResult => html`
     laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in
     voluptate velit esse cillum dolore eu fugiat nulla pariatur.
   </p>
-  <sbb-secondary-button style=${last ? 'margin-block-end: 3rem;' : nothing}
-    >See more</sbb-secondary-button
-  >
+  <sbb-secondary-button style=${last ? 'margin-block-end: 3rem;' : nothing}>
+    See more
+  </sbb-secondary-button>
+`;
+
+const card = (title: string): TemplateResult => html`
+  <sbb-card size="xxl">
+    <sbb-title level="5">${title}</sbb-title>
+    <p class="sbb-text-s" style="margin: 0">
+      Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut
+      labore et dolore magna aliqua.
+    </p>
+    <sbb-secondary-button style="margin-block-start: var(--sbb-spacing-responsive-xs)">
+      See more
+    </sbb-secondary-button>
+  </sbb-card>
 `;
 
 const color: InputType = {
@@ -43,16 +59,24 @@ const backgroundExpanded: InputType = {
   },
 };
 
+const imageSrc: InputType = {
+  control: {
+    type: 'text',
+  },
+};
+
 const defaultArgTypes: ArgTypes = {
   color,
   expanded,
   'background-expanded': backgroundExpanded,
+  'image-src': imageSrc,
 };
 
 const defaultArgs: Args = {
   color: color.options![0],
   expanded: false,
   'background-expanded': false,
+  'image-src': undefined,
 };
 
 const DefaultTemplate = (args: Args): TemplateResult => html`
@@ -62,6 +86,33 @@ const DefaultTemplate = (args: Args): TemplateResult => html`
   </sbb-container>
 `;
 
+const BackgroundImageTemplate = ({ 'image-src': imageSrc, ...args }: Args): TemplateResult => html`
+  <sbb-container ${sbbSpread(args)}>
+    <sbb-title level="2">Container with background image</sbb-title>
+    <style>
+      .content {
+        padding: var(--sbb-spacing-responsive-m) 0;
+        display: flex;
+        gap: var(--sbb-spacing-fixed-6x);
+        justify-content: center;
+        flex-direction: column;
+
+        /* Starting from breakpoint medium. Please use design token. */
+        @media screen and (width >= 840px) {
+          flex-direction: row;
+        }
+      }
+    </style>
+    <div class="content">${card('Example title')} ${card('Another one')}</div>
+    <sbb-image
+      slot="image"
+      image-src=${imageSrc}
+      alt="Train"
+      style="--sbb-image-object-position: bottom;"
+    ></sbb-image>
+  </sbb-container>
+`;
+
 // Only for visual regression
 const NestedContainerTemplate = (): TemplateResult => html`
   <sbb-container color="white">
@@ -92,6 +143,15 @@ export const Milk: StoryObj = {
   args: { ...defaultArgs, color: color.options![2] },
 };
 
+export const BackgroundImage: StoryObj = {
+  render: BackgroundImageTemplate,
+  argTypes: defaultArgTypes,
+  args: {
+    ...defaultArgs,
+    'image-src': sampleImages[7],
+  },
+};
+
 export const Expanded: StoryObj = {
   render: DefaultTemplate,
   argTypes: defaultArgTypes,

src/elements/container/container/container.ts

@@ -7,15 +7,19 @@ import {
 } from 'lit';
 import { customElement, property } from 'lit/decorators.js';
 
+import { slotState } from '../../core/decorators.js';
+
 import style from './container.scss?lit&inline';
 
 /**
  * It displays its content with the default page spacing.
  *
  * @slot - Use the unnamed slot to add anything to the container.
  * @slot sticky-bar - The slot used by the sbb-sticky-bar component.
+ * @slot image - The slot used to slot an `sbb-image` to use as background.
  */
 @customElement('sbb-container')
+@slotState()
 export class SbbContainerElement extends LitElement {
   public static override styles: CSSResultGroup = style;
 
@@ -40,7 +44,10 @@ export class SbbContainerElement extends LitElement {
   protected override render(): TemplateResult {
     return html`
       <div class="sbb-container">
-        <slot></slot>
+        <slot name="image"></slot>
+        <div class="sbb-container__content">
+          <slot></slot>
+        </div>
       </div>
       <slot name="sticky-bar"></slot>
     `;

src/elements/container/container/container.visual.spec.ts

@@ -2,17 +2,42 @@ import { SbbBreakpointUltraMin } from '@sbb-esta/lyne-design-tokens';
 import { setViewport } from '@web/test-runner-commands';
 import { html, type TemplateResult } from 'lit';
 
-import { describeViewports, visualDiffDefault } from '../../core/testing/private.js';
+import {
+  describeViewports,
+  loadAssetAsBase64,
+  visualDiffDefault,
+} from '../../core/testing/private.js';
+import { waitForImageReady } from '../../core/testing.js';
 
-import './container.js';
-import '../../title.js';
 import '../../button.js';
+import '../../card.js';
+import '../../image.js';
+import '../../title.js';
+import './container.js';
+
+const imageUrl = import.meta.resolve('../../core/testing/assets/placeholder-image.png');
+const imageBase64 = await loadAssetAsBase64(imageUrl);
 
 describe(`sbb-container`, () => {
   const colorCases = ['transparent', 'white', 'milk'];
 
   const backgroundExpandedCases = [false, true];
 
+  const images = [
+    {
+      selector: 'sbb-image',
+      image: html`<sbb-image slot="image" image-src=${imageUrl}></sbb-image>`,
+    },
+    {
+      selector: 'img',
+      image: html`<img
+      slot="image"
+      src=${imageBase64}
+      alt=''
+    ></img>`,
+    },
+  ];
+
   const containerContent = (): TemplateResult => html`
     <sbb-title level="4">Example title</sbb-title>
     <p class="sbb-text-s">The container component will give its content the correct spacing.</p>
@@ -25,6 +50,14 @@ describe(`sbb-container`, () => {
     <sbb-secondary-button style="margin-block-end: 3rem;">See more</sbb-secondary-button>
   `;
 
+  const backgroundImageContent = html`
+    <sbb-title level="2">Container with background image</sbb-title>
+    <sbb-card size="xxl" style="margin-bottom: var(--sbb-spacing-responsive-xs)">
+      Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut
+      labore et dolore magna aliqua.
+    </sbb-card>
+  `;
+
   const wrapperStyles = { backgroundColor: 'var(--sbb-color-silver)', padding: '0' };
 
   describeViewports({ viewportHeight: 600 }, () => {
@@ -49,6 +82,27 @@ describe(`sbb-container`, () => {
         );
       }),
     );
+
+    describe('background-image', () => {
+      for (const expanded of [false, true]) {
+        describe(`expanded=${expanded}`, () => {
+          for (const image of images) {
+            it(
+              `slotted=${image.selector}`,
+              visualDiffDefault.with(async (setup) => {
+                await setup.withFixture(
+                  html`<sbb-container ?expanded=${expanded}>
+                    ${backgroundImageContent} ${image.image}
+                  </sbb-container>`,
+                );
+
+                await waitForImageReady(setup.snapshotElement.querySelector(image.selector)!);
+              }),
+            );
+          }
+        });
+      }
+    });
   });
 
   describeViewports({ viewports: ['medium'] }, () => {

src/elements/container/container/readme.md

@@ -14,6 +14,9 @@ The `sbb-container` is a component that displays its content with the default pa
 
 The `sbb-container` content is provided via an unnamed slot.
 
+The `image` slot can be used to place a background image. If you need to control the object position,
+use CSS object-position for slotted `img`, or `--sbb-image-object-position` variable for slotted `sbb-image`.
+
 ## Style
 
 By default `sbb-container` uses the `page spacing` defined in the [layout documentation](/docs/styles-layout--docs). Optionally the user can use the `expanded` property (default: `false`) to switch to the `page spacing expanded` layout.
@@ -36,7 +39,8 @@ The component has also four color variants that can be set using the `color` pro
 
 ## Slots
 
-| Name         | Description                                            |
-| ------------ | ------------------------------------------------------ |
-|              | Use the unnamed slot to add anything to the container. |
-| `sticky-bar` | The slot used by the sbb-sticky-bar component.         |
+| Name         | Description                                                |
+| ------------ | ---------------------------------------------------------- |
+|              | Use the unnamed slot to add anything to the container.     |
+| `image`      | The slot used to slot an `sbb-image` to use as background. |
+| `sticky-bar` | The slot used by the sbb-sticky-bar component.             |

src/elements/overlay/__snapshots__/overlay.snapshot.spec.snap.js

@@ -32,6 +32,7 @@ snapshots["sbb-overlay renders Shadow DOM"] =
         <sbb-container
           class="sbb-overlay__content-container"
           color="transparent"
+          data-slot-names="unnamed"
         >
           <slot>
           </slot>