diff --git a/e2e/tests/auto-nav-sidebar-dir-convension.test.ts b/e2e/tests/auto-nav-sidebar-dir-convension.test.ts
index 4a3db7b19..f0edee040 100644
--- a/e2e/tests/auto-nav-sidebar-dir-convension.test.ts
+++ b/e2e/tests/auto-nav-sidebar-dir-convension.test.ts
@@ -35,7 +35,7 @@ test.describe('Auto nav and sidebar dir convention', async () => {
         'index md convention',
         'index mdx convention',
         'same name',
-        'index in metaIndex In Meta',
+        'index in metaIndex in meta',
         'no meta md',
         'no meta mdx',
       ].join(','),
diff --git a/e2e/tests/auto-nav-sidebar-no-meta.test.ts b/e2e/tests/auto-nav-sidebar-no-meta.test.ts
index 8137a91b3..669341a04 100644
--- a/e2e/tests/auto-nav-sidebar-no-meta.test.ts
+++ b/e2e/tests/auto-nav-sidebar-no-meta.test.ts
@@ -30,9 +30,9 @@ test.describe('Auto nav and sidebar test', async () => {
     expect(sidebarTexts.join(',')).toEqual(
       [
         'API',
-        'pluginPlugin APlugin B',
+        'pluginPlugin aPlugin b',
         'Commands',
-        'configBasic ConfigBuild ConfigFront Matter ConfigTheme Config',
+        'configBasic configBuild configFront matter configTheme config',
       ].join(','),
     );
   });
diff --git a/e2e/tests/auto-nav-sidebar.test.ts b/e2e/tests/auto-nav-sidebar.test.ts
index 2b83d12a9..cd9381527 100644
--- a/e2e/tests/auto-nav-sidebar.test.ts
+++ b/e2e/tests/auto-nav-sidebar.test.ts
@@ -47,11 +47,11 @@ test.describe('Auto nav and sidebar test', async () => {
     const h3Texts = await Promise.all(h3.map(element => element.textContent()));
     expect(h3Texts.join(',')).toEqual(
       [
-        'Basic Config',
-        'Theme Config',
-        'Front Matter Config',
-        'Build Config',
-        'Extname Config',
+        'Basic config',
+        'Theme config',
+        'Front matter config',
+        'Build config',
+        'Extname config',
         'Nested',
         'Runtime API',
         'Components',
@@ -69,7 +69,7 @@ test.describe('Auto nav and sidebar test', async () => {
         'nav',
         'sidebar',
         'builderConfig',
-        'Default Config',
+        'Default config',
         'markdown',
         'markdown.remarkPlugins',
         'Usage',
@@ -91,11 +91,11 @@ test.describe('Auto nav and sidebar test', async () => {
     const h2Texts = await Promise.all(h2.map(element => element.textContent()));
     expect(h2Texts.join(',')).toEqual(
       [
-        'Basic Config',
-        'Theme Config',
-        'Front Matter Config',
-        'Build Config',
-        'Extname Config',
+        'Basic config',
+        'Theme config',
+        'Front matter config',
+        'Build config',
+        'Extname config',
         'Nested',
       ].join(','),
     );
@@ -104,12 +104,12 @@ test.describe('Auto nav and sidebar test', async () => {
     const h3Texts = await Promise.all(h3.map(element => element.textContent()));
     expect(h3Texts.join(',')).toEqual(
       [
-        'Basic Config',
-        'Theme Config',
-        'Front Matter Config',
-        'Build Config',
-        'Extname Config',
-        'Nested Config',
+        'Basic config',
+        'Theme config',
+        'Front matter config',
+        'Build config',
+        'Extname config',
+        'Nested config',
       ].join(','),
     );
 
@@ -122,7 +122,7 @@ test.describe('Auto nav and sidebar test', async () => {
         'nav',
         'sidebar',
         'builderConfig',
-        'Default Config',
+        'Default config',
         'markdown',
         'markdown.remarkPlugins',
         'Nested H2',
@@ -173,7 +173,7 @@ test.describe('Auto nav and sidebar test', async () => {
 
     const h3 = await page.$$('.overview-group_8f375 h3');
     const h3Texts = await Promise.all(h3.map(element => element.textContent()));
-    expect(h3Texts.join(',')).toEqual(['Nested Config'].join(','));
+    expect(h3Texts.join(',')).toEqual(['Nested config'].join(','));
 
     const a = await page.$$('.overview-group_8f375 ul a');
     const aTexts = await Promise.all(a.map(element => element.textContent()));
diff --git a/e2e/tests/basic.test.ts b/e2e/tests/basic.test.ts
index f230994f0..2df2229a1 100644
--- a/e2e/tests/basic.test.ts
+++ b/e2e/tests/basic.test.ts
@@ -23,7 +23,7 @@ test.describe('basic test', async () => {
     await page.goto(`http://localhost:${appPort}`);
     const h1 = await page.$('h1');
     const text = await page.evaluate(h1 => h1?.textContent, h1);
-    expect(text).toContain('Hello World');
+    expect(text).toContain('Hello world');
     // expect the .header-anchor to be rendered and take the correct href
     const headerAnchor = await page.$('.header-anchor');
     const href = await page.evaluate(
diff --git a/e2e/tests/custom-icon.test.ts b/e2e/tests/custom-icon.test.ts
index ffbdb7dfc..8c8e339ac 100644
--- a/e2e/tests/custom-icon.test.ts
+++ b/e2e/tests/custom-icon.test.ts
@@ -25,7 +25,7 @@ test.describe('custom icon test', async () => {
     });
     const h1 = await page.$('h1');
     const text = await page.evaluate(h1 => h1?.textContent, h1);
-    await expect(text).toContain('Hello World');
+    await expect(text).toContain('Hello world');
 
     // TODO: custom icon sometimes failed due to https://github.com/web-infra-dev/rspack/issues/5871
     // const headerAnchor = await page.$('.rspress-nav-search-button img');
diff --git a/e2e/tests/no-config-root.test.ts b/e2e/tests/no-config-root.test.ts
index 400f0cf60..53b334211 100644
--- a/e2e/tests/no-config-root.test.ts
+++ b/e2e/tests/no-config-root.test.ts
@@ -29,7 +29,7 @@ test.describe('no config.root dev test', async () => {
     await page.goto(`http://localhost:${appPort}`);
     const h1 = await page.$('h1');
     const text = await page.evaluate(h1 => h1?.textContent, h1);
-    expect(text).toContain('Hello World');
+    expect(text).toContain('Hello world');
   });
 });
 
@@ -55,6 +55,6 @@ test.describe('no config.root build and preview test', async () => {
     });
     const h1 = await page.$('h1');
     const text = await page.evaluate(h1 => h1?.textContent, h1);
-    expect(text).toContain('Hello World');
+    expect(text).toContain('Hello world');
   });
 });
diff --git a/e2e/tests/react-19.test.ts b/e2e/tests/react-19.test.ts
index 3ee898752..6d85a011e 100644
--- a/e2e/tests/react-19.test.ts
+++ b/e2e/tests/react-19.test.ts
@@ -23,7 +23,7 @@ test.describe('React 19 test', async () => {
     await page.goto(`http://localhost:${appPort}`);
     const h1 = await page.$('h1');
     const text = await page.evaluate(h1 => h1?.textContent, h1);
-    expect(text).toContain('Hello World');
+    expect(text).toContain('Hello world');
   });
 
   test('404 page', async ({ page }) => {
diff --git a/packages/create-rspress/template-basic/docs/_meta.json b/packages/create-rspress/template-basic/docs/_meta.json
index aa4a9a2fc..ee21b24f2 100644
--- a/packages/create-rspress/template-basic/docs/_meta.json
+++ b/packages/create-rspress/template-basic/docs/_meta.json
@@ -5,7 +5,7 @@
     "activeMatch": "/guide/"
   },
   {
-    "text": "Hello World",
+    "text": "Hello world",
     "link": "/hello/",
     "activeMatch": "/hello/"
   },
diff --git a/packages/create-rspress/template-basic/docs/guide/index.md b/packages/create-rspress/template-basic/docs/guide/index.md
index 1200b015e..a75c95c3c 100644
--- a/packages/create-rspress/template-basic/docs/guide/index.md
+++ b/packages/create-rspress/template-basic/docs/guide/index.md
@@ -29,7 +29,7 @@ You can add Front Matter at the beginning of your Markdown file, which is a YAML
 
 ```yaml
 ---
-title: Hello World
+title: Hello world
 ---
 ```
 
@@ -39,7 +39,7 @@ You can also access properties defined in Front Matter in the body, for example:
 
 ```markdown
 ---
-title: Hello World
+title: Hello world
 ---
 
 # {frontmatter.title}
@@ -48,7 +48,7 @@ title: Hello World
 The previously defined properties will be passed to the component as `frontmatter` properties. So the final output will be:
 
 ```html
-<h1>Hello World</h1>
+<h1>Hello world</h1>
 ```
 
 ## Custom container
diff --git a/packages/create-rspress/template-basic/docs/hello.md b/packages/create-rspress/template-basic/docs/hello.md
index d08771599..0e509541c 100644
--- a/packages/create-rspress/template-basic/docs/hello.md
+++ b/packages/create-rspress/template-basic/docs/hello.md
@@ -1,4 +1,4 @@
-# Hello World!
+# Hello world!
 
 ## Start
 
diff --git a/packages/document/docs/en/guide/basic/use-mdx.mdx b/packages/document/docs/en/guide/basic/use-mdx.mdx
index 9b6628849..c303ba990 100644
--- a/packages/document/docs/en/guide/basic/use-mdx.mdx
+++ b/packages/document/docs/en/guide/basic/use-mdx.mdx
@@ -58,7 +58,7 @@ You can add Front Matter at the beginning of your Markdown file, which is a YAML
 
 ```yaml
 ---
-title: Hello World
+title: Hello world
 ---
 ```
 
@@ -68,7 +68,7 @@ You can also access properties defined in Front Matter in the body, for example:
 
 ```markdown
 ---
-title: Hello World
+title: Hello world
 ---
 
 # {frontmatter.title}
@@ -77,7 +77,7 @@ title: Hello World
 The previously defined properties will be passed to the component as `frontmatter` properties. So the final output will be:
 
 ```html
-<h1>Hello World</h1>
+<h1>Hello world</h1>
 ```
 
 ## Custom container
diff --git a/packages/document/docs/en/guide/start/getting-started.mdx b/packages/document/docs/en/guide/start/getting-started.mdx
index 7e143cd25..68ae7321a 100644
--- a/packages/document/docs/en/guide/start/getting-started.mdx
+++ b/packages/document/docs/en/guide/start/getting-started.mdx
@@ -27,7 +27,7 @@ Execute `npm init -y` to initialize a project. You can install Rspress using npm
 Then create the file with the following command
 
 ```bash
-mkdir docs && echo '# Hello World' > docs/index.md
+mkdir docs && echo '# Hello world' > docs/index.md
 ```
 
 Add the following script to `package.json`:
diff --git a/packages/document/docs/zh/guide/basic/use-mdx.mdx b/packages/document/docs/zh/guide/basic/use-mdx.mdx
index f786c16e7..6c19d86f7 100644
--- a/packages/document/docs/zh/guide/basic/use-mdx.mdx
+++ b/packages/document/docs/zh/guide/basic/use-mdx.mdx
@@ -58,7 +58,7 @@ export Button = () => <button />;
 
 ```yaml
 ---
-title: Hello World
+title: Hello world
 ---
 ```
 
@@ -68,7 +68,7 @@ title: Hello World
 
 ```mdx
 ---
-title: Hello World
+title: Hello world
 ---
 
 # {frontmatter.title}
@@ -77,7 +77,7 @@ title: Hello World
 前面定义的属性将作为 `frontmatter` 属性传递给组件。所以最终输出将是：
 
 ```html
-<h1>Hello World</h1>
+<h1>Hello world</h1>
 ```
 
 ## 自定义容器
diff --git a/packages/document/docs/zh/guide/start/getting-started.mdx b/packages/document/docs/zh/guide/start/getting-started.mdx
index 61aec257a..7e685dac3 100644
--- a/packages/document/docs/zh/guide/start/getting-started.mdx
+++ b/packages/document/docs/zh/guide/start/getting-started.mdx
@@ -27,7 +27,7 @@ mkdir rspress-app && cd rspress-app
 然后通过如下命令创建文件:
 
 ```bash
-mkdir docs && echo '# Hello World' > docs/index.md
+mkdir docs && echo '# Hello world' > docs/index.md
 ```
 
 在 `package.json` 中加上如下的脚本: