> For the complete documentation index, see [llms.txt](https://bemtv.gitbook.io/bemtvjs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bemtv.gitbook.io/bemtvjs/introducing-brackethtml.md).

# Introducing Brackethtml

Consider this variable declaration:

```javascript
const btn = `button[Click me!]`;
```

This syntax is called “Brackethtml” it reduces the redundancy of HTML and still can be easily understood as HTML, in addition to supporting HTML normally.

### **Brackethtml + CSS-in-JS (**[**goober**](https://github.com/cristianbote/goober)**)**

Brackethtml already comes with a built-in CSS-in-JS library. In the previous examples, if we wanted to add some style to our button we could do:

```javascript
const btn = `button[color:blue; ~ Click me!]`;
```

### **Usage rules**

The list below describes the usage rules:

* The HTML tag name must be followed by square brackets:

```javascript
const btn = `button[]`;
```

* The `~` symbol must be used inside tags that may contain children to separate attributes and CSS-in-JS from their children, and must be used between whitespace:

```javascript
const btn = `h1[color:blue; ~ Hey!] img[src="my-avatar.png"]`;
```

* Tag attributes must always come before CSS-in-JS and use only double quotes `"`:

```javascript
const btn = `button[data-username = "Bemtv" padding:50px; ~ Hello!]`;
```

* CSS-in-JS must only use single quotes `'`:

```javascript
const btn = `button[class="hello" font-family:'Courier New'; ~ Click me!]`;
```

### **Special characters**

Some characters should be escaped to be used without Brackethtml interpreting them: `~`, `[`, `]`, `#`, `@`, and `$`.

To escape them just wrap them in parentheses `(` `)`:

```javascript
const btn = `button[Click (~) me!]`;
```


---

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