npm install @polymer/iron-icons html <link rel="stylesheet" href="/path/to/iron-icons/iron-icons.html"> html <link rel="stylesheet" href="/path/to/iron-icons/social-icons.html"> html <iron-icon icon="favorite"></iron-icon> html <iron-icon icon="favorite" size="24"></iron-icon> html <iron-icon icon="favorite" style="color: red;"></iron-icon>