const template = document.createElement('template'); template.innerHTML = ` <style> #card { align-items: flex-start; background-color: var(--wc-card-background-color); border-radius: var(--wc-card-border-radius); box-shadow: var(--wc-card-box-shadow); display: flex; flex-flow: row nowrap; justify-content: flex-start; margin-bottom: 1em; padding: var(--single-gap) 1.1rem var(--single-gap) 1.1rem; width: 100%; } </style> <div id="card" part="main"> <slot></slot> </div> ` class card extends HTMLElement { constructor() { super(); this._shadowRoot = this.attachShadow({ 'mode': 'open' }); this._shadowRoot.appendChild(template.content.cloneNode(true)); } } window.customElements.define('wc-card', card);