disabled attribute

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  isDisabled: false,
  actions: {
    toggle() {
      this.toggleProperty('isDisabled');
    }
  }
});

styles.app.css

body {
  margin: 12px 16px;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}

a[disabled] {
  color: red;
}

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
<a disabled={{isDisabled}}>link</a>
<br>
<button onclick={{action "toggle"}}>toggle</button>
<br>

twiddle.json

{
  "version": "0.10.5",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.7.3",
    "ember-data": "2.8.0",
    "ember-template-compiler": "2.7.3",
    "ember-testing": "2.7.3"
  },
  "addons": {}
}