[](https://www.npmjs.com/package/@polymer/iron-flex-layout) [](https://travis-ci.org/PolymerElements/iron-flex-layout) [](https://webcomponents.org/element/@polymer/iron-flex-layout) ## <iron-flex-layout> The `` component provides simple ways to use [CSS flexible box layout](https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Flexible_boxes), also known as flexbox. Note that this is an old element, that was written before all modern browsers had non-prefixed flex styles. As such, nowadays you don't really need to use this element anymore, and can use CSS flex styles directly in your code. See: [Documentation](https://www.webcomponents.org/element/@polymer/iron-flex-layout), [Demo](https://www.webcomponents.org/element/@polymer/iron-flex-layout/demo/demo/index.html). This component provides two different ways to use flexbox: 1. [Layout classes](https://github.com/PolymerElements/iron-flex-layout/tree/master/iron-flex-layout-classes.html). The layout class stylesheet provides a simple set of class-based flexbox rules, that let you specify layout properties directly in markup. You must include this file in every element that needs to use them. 1. [Custom CSS mixins](https://github.com/PolymerElements/iron-flex-layout/blob/master/iron-flex-layout.html). The mixin stylesheet includes custom CSS mixins that can be applied inside a CSS rule using the `@apply` function. ## Usage ### Installation ``` npm install --save @polymer/iron-flex-layout ``` ### In a Polymer 3 element ```js import {PolymerElement, html} from '@polymer/polymer'; import '@polymer/iron-flex-layout/iron-flex-layout-classes.js'; class SampleElement extends PolymerElement { static get template() { return html`

horizontal layout center alignment

`; } } customElements.define('sample-element', SampleElement); ``` ## Contributing If you want to send a PR to this element, here are the instructions for running the tests and demo locally: ### Installation ```sh git clone https://github.com/PolymerElements/iron-flex-layout cd iron-flex-layout npm install npm install -g polymer-cli ``` ### Running the demo locally ```sh polymer serve --npm open http://127.0.0.1:/demo/ ``` ### Running the tests ```sh polymer test --npm ```