doc: update README.md

Author: jaywcjlove

README.md

@@ -141,17 +141,17 @@ Currently not supported, according to the [official documentation](https://devel
 </g>
 ```
 
-## How to Enable Multi-Color Support for Custom Symbols?
+### How to Enable Multi-Color Support for Custom Symbols?
 
 Thanks to [@ldowens](https://github.com/jaywcjlove/create-custom-symbols/issues/9) for providing a method to enable multi-color support for custom symbols.
 
-### Step 1: Create and Export the Symbol  
+#### Step 1: Create and Export the Symbol  
 
 In the **Create Custom Symbols** application, create a new symbol using **SVG** and export it.  
 
 ![Create Symbol](./assets/multi-color-support/001.png)
 
-### Step 2: Import into SF Symbols and Set Colors  
+#### Step 2: Import into SF Symbols and Set Colors  
 
 Drag the exported **Symbols.symbols.svg** file into the **SF Symbols** application and create layers.  
 
@@ -161,13 +161,13 @@ Follow the steps below to set colors for your custom symbol:
 
 ![Set Colors](./assets/multi-color-support/003.png)  
 
-### Step 3: Export the Multi-Color Symbol  
+#### Step 3: Export the Multi-Color Symbol  
 
 Once the colors are set, export the symbol icon from the **SF Symbols** application.  
 
 ![Export Symbol](./assets/multi-color-support/004.png)  
 
-## [More FAQs…](https://github.com/jaywcjlove/create-custom-symbols/issues)
+### [More FAQs…](https://github.com/jaywcjlove/create-custom-symbols/issues)
 
 <!--idoc:config:
 site: Create Custom Symbols

README.zh.md

@@ -141,17 +141,17 @@ Text("使用 \(Image("myCustomSymbolName")) 裁剪图像")
 </g>
 ```
 
-## 如何为自定义符号启用多色支持？
+### 如何为自定义符号启用多色支持？
 
 感谢 [@ldowens](https://github.com/jaywcjlove/create-custom-symbols/issues/9) 提供的方法，帮助我们实现自定义符号的多色支持。
 
-### 步骤 1：创建并导出符号  
+#### 步骤 1：创建并导出符号  
 
 在 **Create Custom Symbols** 应用中，使用 **SVG** 创建一个新的符号，并将其导出。  
 
 ![创建符号](./assets/multi-color-support/001.png)
 
-### 步骤 2：导入 SF Symbols 并设置颜色  
+#### 步骤 2：导入 SF Symbols 并设置颜色  
 
 将导出的 **Symbols.symbols.svg** 文件拖拽到 **SF Symbols** 应用中，并创建层。  
 
@@ -161,13 +161,13 @@ Text("使用 \(Image("myCustomSymbolName")) 裁剪图像")
 
 ![设置颜色](./assets/multi-color-support/003.png)  
 
-### 步骤 3：导出多色符号  
+#### 步骤 3：导出多色符号  
 
 完成颜色设置后，在 **SF Symbols** 应用中导出符号图标。  
 
 ![导出符号](./assets/multi-color-support/004.png)  
 
-## [更多问题...](https://github.com/jaywcjlove/create-custom-symbols/issues)
+### [更多问题...](https://github.com/jaywcjlove/create-custom-symbols/issues)
 
 <!--idoc:config:
 site: 创建自定义符号