> For the complete documentation index, see [llms.txt](https://dev.ubidots.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dev.ubidots.com/dashboards-and-widgets/html-canvas/code-editor/css-tab.md).
# CSS tab
CSS (Cascading Style Sheets) defines styles that apply to HTML elements and customize how they appear in the browser.
### Examples
| CSS Element | Effect on the corresponding HTML element |
| ---------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
|
body { background-color: lightblue; }
| Sets the HTML body background color to *lightblue* |
|
h1 { color: white; text-align: center; }
| Sets `h1` headings to use the color *white* and centers the text |
|
p { font-family: verdana; font-size: 20px; }
| Sets paragraphs to use the *verdana* font family and a font size of 20px |
### Advanced example
The following HTML + CSS file modifies the styles of the body, `h1`, and paragraph elements.
```html
This is a h1 header
This is a paragraph
```
It results in the following content in the browser:
To achieve this on the HTML Canvas:
* Add the following code to the HTML code editor tab:
```html
This is a h1 header
This is a paragraph
```
* Add the following code to the CSS tab:
```css
body {
background-color: lightblue;
}
h1 {
color: white;
text-align: center;
}
p {
font-family: verdana;
font-size: 20px;
}
```
This is the resulting HTML Canvas widget on a dashboard:
---
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