HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.
In CodePen, whatever you write in the HTML editor is what goes within the <body>
tags in a basic HTML5 template. So you don't have access to higher-up elements like the <html>
tag. If you want to add classes there that can affect the whole document, this is the place to do it.
In CodePen, whatever you write in the HTML editor is what goes within the <body>
tags in a basic HTML5 template. If you need things in the <head>
of the document, put that code here.
The resource you are linking to is using the 'http' protocol, which may not work when the browser is using https.
CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.
It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.
To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit-
or -moz-
.
We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).
Any URLs added here will be added as <link>
s in order, and before the CSS in the editor. You can use the CSS from another Pen by using its URL and the proper URL extension.
You can apply CSS to your Pen from any stylesheet on the web. Just put a URL to it here and we'll apply it, in the order you have them, before the CSS in the Pen itself.
You can also link to another Pen here (use the .css
URL Extension) and we'll pull the CSS from that Pen and include it. If it's using a matching preprocessor, use the appropriate URL Extension and we'll combine the code before preprocessing, so you can use the linked Pen as a true dependency.
JavaScript preprocessors can help make authoring JavaScript easier and more convenient.
Babel includes JSX processing.
Any URL's added here will be added as <script>
s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.
You can apply a script from anywhere on the web to your Pen. Just put a URL to it here and we'll add it, in the order you have them, before the JavaScript in the Pen itself.
If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.
You can also link to another Pen here, and we'll pull the JavaScript from that Pen and include it. If it's using a matching preprocessor, we'll combine the code before preprocessing, so you can use the linked Pen as a true dependency.
Search for and use JavaScript packages from npm here. By selecting a package, an import
statement will be added to the top of the JavaScript editor for this package.
Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.
All packages are different, so refer to their docs for how they work.
If you're using React / ReactDOM, make sure to turn on Babel for the JSX processing.
If active, Pens will autosave every 30 seconds after being saved once.
If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.
If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.
Visit your global Editor Settings.
<body data-step="0">
<svg xmlns="http://www.w3.org/2000/svg" style="display: none;">
<defs>
<symbol id="note" viewBox="0 0 121 174">
<path d="M72.517 141.958c.741 13.022-12.003 26.182-30.168 30.376-19.642 4.534-38.183-3.132-41.414-17.123-3.23-13.992 10.075-29.01 29.716-33.545 7.576-1.749 14.988-1.683 21.42-.139L52 115.424V0c11.37 11.855 20.084 19.909 26.142 24.16 9.087 6.377 21.997 14.68 30.63 25.999 8.633 11.318 12.207 22.805 11.035 33.937-1.172 11.132-3.8 19.104-8.8 26.987-3.333 5.256-5.444 8.71-6.332 10.36 2.344-11.277 3.06-20.35 2.15-27.22-1.364-10.304-3.914-15.369-12.356-21.72-5.628-4.234-12.885-7.564-21.77-9.991v79.493l-.182-.047z" fill-rule="evenodd"/>
</symbol>
</defs>
</svg>
<div id="countdown">01:00</div>
<div id="screen-wrapper">
<div id="screens">
<div class="screen step0"></div>
<div class="screen step1">
<div class="lock-input">
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
</div>
<p class="hint">Hint: "Amazing Grace" in F</p>
</div>
<div class="screen step2">
<div class="lock-input">
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
<div class="note"><svg><use xlink:href="#note"></use></svg></div>
</div>
<p class="hint">Hint: C7 in root position</p>
</div>
<div class="screen step3">
<p>You win!!</p>
</div>
</div>
</div>
</body>
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
html, body {
height: 100%;
}
body {
background: radial-gradient(#111628, #0b0f1d);
font-family: 'Roboto Mono', Arial, sans-serif;
}
body::before {
content: "";
position: fixed;
top: 0;
width: 100%;
height: 100%;
background: radial-gradient(rgba(24, 56, 24, 0.57), rgba(40, 109, 40, 0.68));
opacity: 0;
transition: 150ms ease;
z-index: -1;
will-change: opacity;
}
body.success::before {
animation: success 2.5s;
}
body::after {
content: "";
position: fixed;
top: 0;
width: 100%;
height: 100%;
background: radial-gradient(rgba(244, 67, 54, 0.8), rgba(206, 55, 44, 0.48));
opacity: 0;
transition: 500ms ease;
z-index: -1;
will-change: opacity;
}
body.gameover::after {
opacity: 1;
}
#countdown {
height: 20vh;
position: absolute;
top: 0;
left: 0;
color: #fff;
text-align: center;
font-size: 15vh;
line-height: 20vh;
width: 100%;
border-bottom: 1px solid rgba(255,255,255,0.1);
}
#screen-wrapper {
overflow: hidden;
height: 100vh;
}
#screens {
width: 400%;
height: 100%;
color: #ffffff;
display: flex;
align-items: center;
transition: 500ms ease;
will-change: transform;
}
[data-step="1"] #screens {
transform: translateX(-100vw);
}
[data-step="2"] #screens {
transform: translateX(-200vw);
}
[data-step="3"] #screens {
transform: translateX(-300vw);
}
.screen {
flex: 1 0 25%;
text-align: center;
padding: 2em;
}
.lock-input {
background: #fff1dc;
padding: 50px 75px;
border-radius: 15px;
box-shadow: 0px 2px 5px #000;
margin: 20px 0;
text-align: center;
overflow: hidden;
transition: 150ms ease;
display: inline-block;
}
.lock-input.error {
background: #ffacba;
animation: shake 300ms;
}
.note {
display: inline-block;
}
.note svg {
width: 55px;
height: 75px;
transform: translateY(150px);
transition: 150ms cubic-bezier(0.18, 0.89, 0.32, 1.28);
}
.note.on svg {
transform: translateY(0px);
}
.step0, .step3 {
font-size: 3vw;
}
.hint {
font-weight: 100;
font-style: italic;
font-size: 0.8em;
}
@keyframes success {
0% {
opacity: 0;
}
10% {
opacity: 1;
}
30% {
opacity: 1;
}
100% {
opacity: 0;
}
}
@keyframes shake {
0% {
transform: translateX(0px);
}
25% {
transform: translateX(-5px);
}
75% {
transform: translateX(5px);
}
100% {
transform: translateX(0px);
}
}
// Variable which tell us what step of the game we're on.
// We'll use this later when we parse noteOn/Off messages
var currentStep = 0;
// Timer length
var timerLength = 1; // in minutes
// Lock 1 variables
var correctNoteSequence = [60, 65, 69, 65, 69, 67, 65, 62, 60]; // Amazing Grace in F
var activeNoteSequence = [];
// Lock 2 variables
var correctChord = [60, 64, 67, 70]; // C7 chord starting on middle C
var activeChord = [];
if (navigator.requestMIDIAccess) {
console.log('This browser supports WebMIDI!');
navigator.requestMIDIAccess().then(onMIDISuccess, onMIDIFailure);
} else {
console.log('WebMIDI is not supported in this browser.');
document.querySelector('.step0').innerHTML = 'Error: This browser does not support WebMIDI.';
}
function onMIDISuccess(midiAccess) {
document.querySelector('.step0').innerHTML = 'Press any note to begin...';
var inputs = midiAccess.inputs;
var outputs = midiAccess.outputs;
for (var input of midiAccess.inputs.values()) {
input.onmidimessage = getMIDIMessage;
}
}
function onMIDIFailure() {
document.querySelector('.step0').innerHTML = 'Error: Could not access MIDI devices. Connect a device and refresh to try again.';
}
function getMIDIMessage(message) {
var command = message.data[0];
var note = message.data[1];
var velocity = (message.data.length > 2) ? message.data[2] : 0; // a velocity value might not be included with a noteOff command
switch (command) {
case 144: // noteOn
if (velocity > 0) {
noteOnListener(note, velocity);
} else {
noteOffListener(note);
}
break;
case 128: // noteOff
noteOffCallback(note);
break;
// we could easily expand this switch statement to cover other types of commands such as controllers or sysex
}
}
function noteOnListener(note, velocity) {
switch(currentStep) {
// If the game hasn't started yet.
// The first noteOn message we get will run the first sequence
case 0:
// Run our start up sequence
runSequence('gamestart');
// Increment the currentStep so this is only triggered once
currentStep++;
break;
// The first lock - playing a correct sequence
case 1:
// add the note to the array
activeNoteSequence.push(note);
// show the requisite number of note placeholders
for (var i = 0; i < activeNoteSequence.length; i++) {
document.querySelector('.step1 .note:nth-child(' + (i + 1) + ')').classList.add('on');
}
// when the array is the same length as the correct sequence, compare the two
if (activeNoteSequence.length == correctNoteSequence.length) {
var match = true;
for (var index = 0; index < activeNoteSequence.length; index++) {
if (activeNoteSequence[index] != correctNoteSequence[index]) {
match = false;
break;
}
}
if (match) {
// Run the next sequence and increment the current step
runSequence('lock1');
currentStep++;
} else {
// Clear the array and start over
activeNoteSequence = [];
var lockInput = document.querySelector('.step1 .lock-input');
lockInput.classList.add('error');
window.setTimeout(function(){
lockInput.classList.remove('error');
for (var note of lockInput.querySelectorAll('.note')) {
note.classList.remove('on');
}
}, 500);
}
}
break;
case 2:
// add the note to the active chord array
activeChord.push(note);
// show the number of active notes
for (var i = 0; i < activeChord.length; i++) {
document.querySelector('.step2 .note:nth-child(' + (i + 1) + ')').classList.add('on');
}
// If the array is the same length as the correct chord, compare
if (activeChord.length == correctChord.length) {
var match = true;
for (var index = 0; index < activeChord.length; index++) {
if (correctChord.indexOf(activeChord[index]) < 0) {
match = false;
break;
}
}
if (match) {
runSequence('lock2');
currentStep++;
} else {
var lockInput = document.querySelector('.step2 .lock-input');
lockInput.classList.add('error');
window.setTimeout(function(){
lockInput.classList.remove('error');
}, 500);
}
}
break;
}
}
function noteOffListener(note) {
switch(currentStep) {
case 2:
// Remove the note value from the active chord array
activeChord.splice(activeChord.indexOf(note), 1);
// Hide the last note shown
document.querySelector('.step2 .note:nth-child(' + (activeChord.length + 1) + ')').classList.remove('on');
break;
}
}
function runSequence(sequence) {
switch(sequence) {
case 'gamestart':
// Now we'll start a countdown timer...
startTimer();
// code to trigger animations, give a clue for the first lock
advanceScreen();
successFlicker();
break;
case 'lock1':
// code to trigger animations and give clue for the next lock
advanceScreen();
successFlicker();
break;
case 'lock2':
// code to trigger animations, stop clock, end game
advanceScreen();
successFlicker();
break;
case 'gameover':
currentStep = 3;
document.querySelector('.step3 p').innerHTML = "You lose...";
document.querySelector('body').dataset.step = "3";
document.querySelector('body').classList.add('gameover');
break;
}
}
function advanceScreen() {
document.querySelector('body').dataset.step++;
}
function successFlicker() {
var b = document.querySelector('body')
b.classList.add('success');
window.setTimeout(function(){
b.classList.remove('success');
}, 2500);
}
function startTimer(){
// set timer for 60 minutes from start
var now = new Date();
timeEnd = new Date(now.getTime() + (timerLength*60*1000) - 1);
updateTimer();
}
/**
* Function to update the time remaining every second
*/
function updateTimer() {
var now = new Date();
var distance = timeEnd.getTime() - now.getTime();
var minutes = Math.floor(distance / (1000 * 60));
var seconds = Math.floor((distance % (1000 * 60)) / 1000);
if (minutes < 10) minutes = "0" + minutes;
if (seconds < 10) seconds = "0" + seconds;
if (currentStep < 3) {
document.querySelector('#countdown').innerText = minutes + ":" + seconds;
if (minutes > 0 || seconds > 0) {
window.setTimeout(function() {
updateTimer();
}, 1000);
} else if (minutes == 0 && seconds == 0) {
runSequence('gameover');
}
}
}
var lockInput = document.querySelector('.step2 .lock-input');
lockInput.addEventListener('click', function(){
lockInput.classList.add('error');
window.setTimeout(function(){
lockInput.classList.remove('error');
for (var note of lockInput.querySelectorAll('.note')) {
note.classList.remove('on');
}
}, 500);
});
var notes = lockInput.querySelectorAll('.note');
for (var note of notes) {
note.addEventListener('mouseover', function(){
this.classList.add('on');
});
}
Also see: Tab Triggers