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                <div id="page-wrapper">
  <h1>Battery Status API Demo</h1>

  <p id="msg"></p>

  <!-- Battery Level Meter -->
  <meter min="0" low="0.25" max="1" high="0.75" optimum="1" value="0" id="battery-meter"></meter>

  <!-- Battery Stats -->
  <table id="battery-stats">
        <th>Battery Level</th>
        <th>Charging Status</th>
        <th>Charging Time</th>
        <th>Discharging Time</th>
        <td id="battery-level"></td>
        <td id="battery-status"></td>
        <td id="battery-charging"></td>
        <td id="battery-discharging"></td>



                *, *:before, *:after {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;

html {
  font-family: Helvetica, Arial, sans-serif;
  font-size: 100%;
  background: #333;

#page-wrapper {
  width: 640px;
  background: #FFFFFF;
  padding: 1em;
  margin: 1em auto;
  border-top: 5px solid #69c773;
  box-shadow: 0 2px 10px rgba(0,0,0,0.8);

h1 {
  margin-top: 0;

p {
  font-size: 0.9em;

meter {
  width: 100%;
  height: 60px;
  background: #E6E6E6;

table {
  margin-top: 1em;
  width: 100%;
  text-align: center;

button {
  display: inline-block;
  border-radius: 3px;
  border: none;
  font-size: 0.9rem;
  padding: 0.4rem 0.8em;
  background: #69c773;
  border-bottom: 1px solid #498b50;
  color: white;
  -webkit-font-smoothing: antialiased;
  font-weight: bold;
  margin: 0 0.25rem;
  text-align: center;

button:hover, button:focus {
  opacity: 0.75;
  cursor: pointer;

button:active {
  opacity: 1;
  box-shadow: 0 -3px 10px rgba(0, 0, 0, 0.1) inset;



                // Get the BatteryManager.
var battery = navigator.battery || navigator.mozBattery || navigator.webkitBattery;

var msg = document.getElementById('msg');

// Get the battery meter.
var batteryMeter = document.getElementById('battery-meter');

// Get the data cells in the table.
var batteryLevel = document.getElementById('battery-level');
var batteryStatus = document.getElementById('battery-status');
var batteryCharging = document.getElementById('battery-charging');
var batteryDischarging = document.getElementById('battery-discharging');

// Update the battery level meter (and table value).
function updateBatteryLevel() {
	batteryMeter.value = battery.level;
	batteryLevel.innerHTML = (battery.level * 100) + '%';

// Update the battery charging status.
function updateBatteryStatus() {
	if (battery.charging) {
		batteryStatus.innerHTML = 'Charging';
	} else {
		batteryStatus.innerHTML = 'Not Charging';

// Update the battery charging time value.
function updateBatteryChargingTime() {
	if (battery.chargingTime === Infinity) {
		// Not charging.
		batteryCharging.innerHTML = '-';
	} else {
		// Charging.
		batteryCharging.innerHTML = (battery.chargingTime / 60) + ' minutes';

// Update the battery discharging time value.
function updateBatteryDischargingTime() {
	if (battery.dischargingTime === Infinity) {
		// Not discharging.
		batteryDischarging.innerHTML = '-';
	} else {
		// Discharging.
		batteryDischarging.innerHTML = (battery.dischargingTime / 60) + ' minutes';

// Set initial values and set up event listeners.
function init() {
	// Set initial values.

	// Set up event listeners.
	battery.onlevelchange = updateBatteryLevel;
	battery.onchargingchange = updateBatteryStatus;
	battery.onchargingtimechange = updateBatteryChargingTime;
	battery.ondischargingtimechange = updateBatteryDischargingTime;

// Quick check for browser compatibility.
if (battery) {
	// API Supported!
	msg.innerHTML = 'Your browser supports the Battery Status API.';

	// Initialize the app.
} else {
	// API not supported.
	msg.innerHTML = 'Your browser does not support the Battery Status API :(';