--- title: Configuration --- Quill allows several ways to customize it to suit your needs. This section is dedicated to tweaking existing functionality. See the [Modules](/docs/modules/) section for adding new functionality and the [Themes](/docs/themes/) section for styling. ## Container Quill requires a container where the editor will be appended. You can pass in either a CSS selector or a DOM object. ```javascript const quill = new Quill('#editor'); // First matching element will be used ``` ```javascript const container = document.getElementById('editor'); const quill = new Quill(container); ``` If the container is not empty, Quill will initialize with the existing contents. ## Options To configure Quill, pass in an options object: The following keys are recognized: ### bounds Default: `document.body` DOM Element or a CSS selector for a DOM Element, within which the editor's ui elements (i.e. tooltips, etc.) should be confined. Currently, it only considers left and right boundaries. ### debug Default: `warn` Shortcut for [debug](/docs/api/#debug). Note `debug` is a static method and will affect other instances of Quill editors on the page. Only warning and error messages are enabled by default. ### placeholder Default: None Placeholder text to show when editor is empty. ### readOnly Default: `false` Whether to instantiate the editor to read-only mode. ### theme Name of theme to use. The builtin options are `"bubble"` or `"snow"`. An invalid or falsy value will load a default minimal theme. Note the theme's specific stylesheet still needs to be included manually. See [Themes](/docs/themes/) for more information.