> 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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