chore: misc cleanup for music player project (#52546)

Co-authored-by: Kristofer Koishigawa <scissorsneedfoodtoo@gmail.com>
2026-05-28 18:26:54 +00:00 · 2023-12-14 22:46:07 -08:00
parent 40c832c85c
commit 8d55abcf9f
80 changed files with 879 additions and 263 deletions
@@ -61,288 +61,292 @@
      "title": "Step 12"
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      "title": "Step 80"
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+      "id": "655b49333d9f265bc1512152",
      "title": "Step 81"
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+      "id": "655b4bbff1dbf66cb2ed4dac",
      "title": "Step 82"
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    {
-      "id": "655b4dad1d38ff7cdd65cbfe",
+      "id": "655b4c8f636d9675953a0388",
      "title": "Step 83"
+    },
+    {
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+      "title": "Step 84"
    }
  ],
  "helpCategory": "JavaScript"
@@ -7,9 +7,9 @@ dashedName: step-2

 # --description--

-Continuing with the pattern, access the `#next`, `#previous` and `#shuffle` elements from the HTML file. 
+Access the `#next`, `#previous` and `#shuffle` elements from the HTML file.

-Assign them to the `nextButton`, `previousButton`, and `shuffleButton` variables respectively.
+Assign them to variables named `nextButton`, `previousButton`, and `shuffleButton`, respectively.

 # --hints--

@@ -7,21 +7,21 @@ dashedName: step-7

 # --description--

-All the songs are now in the `allSongs` array. The next step is to initialize the <dfn>Web Audio API</dfn>.
+We've added the rest of the songs to the `allSongs` array for you.

-The Audio API is a component of the Web Audio API specification, offering a high-level interface for processing and synthesizing audio within web applications.
+Next, you'll learn about the <dfn>Web Audio API</dfn> and how to use it to play songs. All modern browsers support the Web Audio API, which lets you generate and process audio in web applications.

-Use `const` to create a variable named `audio` and set it equal to `new Audio()`. This will create a new HTML5 audio element.
+Use `const` to create a variable named `audio` and set it equal to `new Audio()`. This will create a new HTML5 `audio` element.

 # --hints--

-You should use the `new` keyword to intialize the web audio API
+You should use the `new` keyword to create an instance of the `Audio` object.

 ```js
 assert.match(code, /new\s*Audio\(\);?/)
 ```

-You should set the intialization to a constant named `audio`.
+You should assign the `Audio` object to a constant named `audio`.

 ```js
 assert.match(code, /const\s+audio\s*=\s*new\s*Audio\(\);?/)
@@ -1,8 +1,8 @@
 ---
 id: 653283d07b8f9d294aafa83b
-title: Step 20
+title: Step 21
 challengeType: 0
-dashedName: step-20
+dashedName: step-21
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65362bfd67d61d517deef191
-title: Step 21
+title: Step 22
 challengeType: 0
-dashedName: step-21
+dashedName: step-22
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 653635c731206b718659d3d5
-title: Step 22
+title: Step 23
 challengeType: 0
-dashedName: step-22
+dashedName: step-23
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 653639d63a45a077333312c8
-title: Step 23
+title: Step 24
 challengeType: 0
-dashedName: step-23
+dashedName: step-24
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 653641509b6e7681a9333245
-title: Step 25
+title: Step 26
 challengeType: 0
-dashedName: step-25
+dashedName: step-26
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65364566e84e378837fbaf2a
-title: Step 27
+title: Step 28
 challengeType: 0
-dashedName: step-27
+dashedName: step-28
 ---

 # --description--
@@ -7,9 +7,9 @@ dashedName: step-11

 # --description--

-Now you need to show songs to be played in the UI. For this, you'll need to create a `renderSongs` function with an arrow function syntax.
+Now you need a way to display the songs in the UI. To do this, you'll create a `renderSongs` function using the arrow function syntax.

-An arrow function is a shorter and more concise way to write functions in JavaScript. It uses the variable keywords (`var`, `let`, and `const`) and fat arrow syntax (`=>`):
+An arrow function is a shorter and more concise way to write functions in JavaScript. It's a <dfn>function expression</dfn>, which is a function that's assigned to a variable. To write an arrow function, you can use the following syntax:

 ```js
 // Traditional function
@@ -20,12 +20,12 @@ console.log(add(3, 5)); // Output: 8

 // Arrow function
 const addArrow = (a, b) => {
-    return a + b
+  return a + b;
 };
 console.log(addArrow(3, 5)); // Output: 8
 ```

-If the function body consists of a single expression, you don't need the curly braces and the `return` keyword. This is called an `implicit return`.
+If the function body consists of a single expression, you don't need the curly braces and the `return` keyword. This is called an `implicit return`:

 ```js
 const addArrow = (a, b) =>  a + b;
@@ -48,22 +48,22 @@ assert.match(code, /const\s+renderSongs\s*=\s*/)
 assert.isFunction(renderSongs)
 ```

-Your `renderSongs` function should use an arrow syntax.
+Your `renderSongs` function should use the arrow function syntax.

 ```js
-assert.match(code, /const\s+renderSongs\s*=\s*\(.*\)\s*=>\s*/)
+assert.match(code, /const\s+renderSongs\s*=\s*\(?.*\)?\s*=>\s*/)
 ```

-Your `renderSongs` function should take an `array` parameter.
+Your `renderSongs` function should take `array` as a parameter.

 ```js
-assert.match(code, /const\s+renderSongs\s*=\s*\(array/)
+assert.match(code, /const\s+renderSongs\s*=\s*\(?\s*array/)
 ```

-Your `renderSongs` function  should be empty.
+Your `renderSongs` function should be empty.

 ```js
-assert.match(code, /const\s+renderSongs\s*=\s*\(array\)\s*=>\s*\{\n?\s*?\};?/)
+assert.match(code, /const\s+renderSongs\s*=\s*\(?\s*array\s*\)?\s*=>\s*\{\s*\};?/)
 ```

 # --seed--
@@ -7,41 +7,24 @@ dashedName: step-12

 # --description--

-Now you should loop through the array. You will call the `renderSongs` function with the songs array inside the `userData` object. For this we will use the `map()` method.
+Later when you call the `renderSongs` function, you'll pass in the `songs` array inside the `userData` object. When you do, the function will loop through the array and build HTML for all the songs.

-The `map()` method is used to iterate through an array and return a new array. It's helpful when you want to create a new array based on the values of an existing array. For example:
+To do this, you'll use the `map()` method, which you'll learn more about in the following steps.

-```js
-const numbers = [1, 2, 3];
-const doubledNumbers = numbers.map((number) => number * 2); // doubledNumbers will be [2, 4, 6]
-```
-
-Inside the `renderSongs` function, use `const` to create another `songsHTML` function and assign it to `array.map()`. Pass in `song` as the parameter of the `map()` method, a fat arrow, and an empty curly braces.
+For now, use `const` to declare a variable named `songsHTML` and assign it `array.map()`.

 # --hints--

-You should use the `map()` method on `array`.
+You should have a `const` variable called `songsHTML`.

 ```js
-assert.match(code, /array.map\(/)
+assert.match(code, /const\s+songsHTML/);
 ```

-Your `map()` method should have a `song` parameter in it's callback function.
+You should assign `array.map()` to your `songsHTML`.

 ```js
-assert.match(code, /array.map\(\(?song\)?/)
-```
-
-The callback function of your `map()` method should use arrow function syntax.
-
-```js
-assert.match(code, /array.map\(\(?song\)?\s*=>\s*\{\s*\}\)/)
-```
-
-You should assign your `array.map` to a `songsHTML` constant.
-
-```js
-assert.match(code, /const\s+songsHTML\s*=\s*array.map\(\(?song\)?\s*=>\s*\{\s*\}\)/);
+assert.match(code, /const\s+songsHTML\s*=\s*array\.map\(\)/);
 ```

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@@ -1,8 +1,8 @@
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+title: Step 14
 challengeType: 0
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+dashedName: step-27
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6552385244ccf89b77d6b332
-title: Step 36
+title: Step 37
 challengeType: 0
-dashedName: step-36
+dashedName: step-37
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655243068222c2c1166b90b0
-title: Step 37
+title: Step 38
 challengeType: 0
-dashedName: step-37
+dashedName: step-38
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655476e1ff522252fdcce5e4
-title: Step 38
+title: Step 39
 challengeType: 0
-dashedName: step-38
+dashedName: step-39
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655479aa3e1e0360ae38b7a6
-title: Step 39
+title: Step 40
 challengeType: 0
-dashedName: step-39
+dashedName: step-40
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65547ee197840478a1b95f4b
-title: Step 40
+title: Step 41
 challengeType: 0
-dashedName: step-40
+dashedName: step-41
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6554815fe2472f8bfdab7642
-title: Step 41
+title: Step 42
 challengeType: 0
-dashedName: step-41
+dashedName: step-42
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655482742cc5499726e3f347
-title: Step 42
+title: Step 43
 challengeType: 0
-dashedName: step-42
+dashedName: step-43
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655483ebf0096ba02b2c3d4c
-title: Step 43
+title: Step 44
 challengeType: 0
-dashedName: step-43
+dashedName: step-44
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655485321913feabbc5f00f8
-title: Step 44
+title: Step 45
 challengeType: 0
-dashedName: step-44
+dashedName: step-45
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6554860ea4dfbab2f4786fc8
-title: Step 45
+title: Step 46
 challengeType: 0
-dashedName: step-45
+dashedName: step-46
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655487f686aabfc2a10ba887
-title: Step 35
+title: Step 36
 challengeType: 0
-dashedName: step-35
+dashedName: step-36
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65548f747a4cdafd186948d1
-title: Step 46
+title: Step 47
 challengeType: 0
-dashedName: step-46
+dashedName: step-47
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655490f55c36900779336988
-title: Step 47
+title: Step 48
 challengeType: 0
-dashedName: step-47
+dashedName: step-48
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655492e6b90c7a198c587943
-title: Step 49
+title: Step 50
 challengeType: 0
-dashedName: step-49
+dashedName: step-50
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655494d5a15d6a2567e1ea60
-title: Step 50
+title: Step 51
 challengeType: 0
-dashedName: step-50
+dashedName: step-51
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655495a6bd96e42bc3baa795
-title: Step 51
+title: Step 52
 challengeType: 0
-dashedName: step-51
+dashedName: step-52
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555d17af9ff06a14d399f6d
-title: Step 52
+title: Step 53
 challengeType: 0
-dashedName: step-52
+dashedName: step-53
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555d458687cb3b357834df9
-title: Step 53
+title: Step 54
 challengeType: 0
-dashedName: step-53
+dashedName: step-54
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555d729c9bfd7c3195f1948
-title: Step 54
+title: Step 55
 challengeType: 0
-dashedName: step-54
+dashedName: step-55
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555d7e384056dc9c581fadf
-title: Step 55
+title: Step 56
 challengeType: 0
-dashedName: step-55
+dashedName: step-56
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555d8faed60b9d3e4a6cefb
-title: Step 56
+title: Step 57
 challengeType: 0
-dashedName: step-56
+dashedName: step-57
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555dd138e70cae6b546966d
-title: Step 57
+title: Step 58
 challengeType: 0
-dashedName: step-57
+dashedName: step-58
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555de565387a2efe90a6ccc
-title: Step 58
+title: Step 59
 challengeType: 0
-dashedName: step-58
+dashedName: step-59
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e04aeb225bfbae237344
-title: Step 59
+title: Step 60
 challengeType: 0
-dashedName: step-59
+dashedName: step-60
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e0bfe4d69904410f7cd3
-title: Step 60
+title: Step 61
 challengeType: 0
-dashedName: step-60
+dashedName: step-61
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e39a5f4c6f138c7d9405
-title: Step 61
+title: Step 62
 challengeType: 0
-dashedName: step-61
+dashedName: step-62
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e57d3e6d9d221c4735be
-title: Step 62
+title: Step 63
 challengeType: 0
-dashedName: step-62
+dashedName: step-63
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e6cec786da2aadc11ea0
-title: Step 63
+title: Step 64
 challengeType: 0
-dashedName: step-63
+dashedName: step-64
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e7acdbae972d3e8e0f5b
-title: Step 64
+title: Step 65
 challengeType: 0
-dashedName: step-64
+dashedName: step-65
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555e9197bf1d7416bdd76e0
-title: Step 65
+title: Step 66
 challengeType: 0
-dashedName: step-65
+dashedName: step-66
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6555ebf07ec610585a626f72
-title: Step 66
+title: Step 67
 challengeType: 0
-dashedName: step-66
+dashedName: step-67
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65571e742fbf4532d8f98e90
-title: Step 67
+title: Step 68
 challengeType: 0
-dashedName: step-67
+dashedName: step-68
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655720534347cb3f31cdfb3d
-title: Step 68
+title: Step 69
 challengeType: 0
-dashedName: step-68
+dashedName: step-69
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65572399a8e16d50bc2c1ff3
-title: Step 69
+title: Step 70
 challengeType: 0
-dashedName: step-69
+dashedName: step-70
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655724bac464795a0ad91082
-title: Step 71
+title: Step 72
 challengeType: 0
-dashedName: step-71
+dashedName: step-72
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655727b2e1e49d6adf584442
-title: Step 72
+title: Step 73
 challengeType: 0
-dashedName: step-72
+dashedName: step-73
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655729e68e49b277a6b448bd
-title: Step 74
+title: Step 75
 challengeType: 0
-dashedName: step-74
+dashedName: step-75
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65572bb34a7e488224b937fc
-title: Step 75
+title: Step 76
 challengeType: 0
-dashedName: step-75
+dashedName: step-76
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65572e5aaf022790fb4a81b1
-title: Step 76
+title: Step 77
 challengeType: 0
-dashedName: step-76
+dashedName: step-77
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655737cd004591b0271d6826
-title: Step 77
+title: Step 78
 challengeType: 0
-dashedName: step-77
+dashedName: step-78
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65573a97c59ddbbf028ca95e
-title: Step 78
+title: Step 79
 challengeType: 0
-dashedName: step-78
+dashedName: step-79
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65573d0abe4d38cd6fa13f44
-title: Step 79
+title: Step 80
 challengeType: 0
-dashedName: step-79
+dashedName: step-80
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6557421eb6a7a0f0500e3106
-title: Step 70
+title: Step 71
 challengeType: 0
-dashedName: step-70
+dashedName: step-71
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655b49333d9f265bc1512152
-title: Step 80
+title: Step 81
 challengeType: 0
-dashedName: step-80
+dashedName: step-81
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655b4bbff1dbf66cb2ed4dac
-title: Step 81
+title: Step 82
 challengeType: 0
-dashedName: step-81
+dashedName: step-82
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655b4c8f636d9675953a0388
-title: Step 82
+title: Step 83
 challengeType: 0
-dashedName: step-82
+dashedName: step-83
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 655b4dad1d38ff7cdd65cbfe
-title: Step 83
+title: Step 84
 challengeType: 0
-dashedName: step-83
+dashedName: step-84
 ---

 # --description--
@@ -10,11 +10,11 @@ dashedName: step-6
 Add a third object with the following properties and values:

 ```js
-  id: 2,
-  title: "Still Learning",
-  artist: "Quincy Larson",
-  duration: "3:51",
-  src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/still-learning.mp3",
+id: 2,
+title: "Still Learning",
+artist: "Quincy Larson",
+duration: "3:51",
+src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/still-learning.mp3",
 ```

 # --hints--
@@ -7,9 +7,9 @@ dashedName: step-9

 # --description--

-Now you should update the `userData` object to include a `songs` property. For this you will be using the `spread` operator.
+Since users will be able to shuffle and delete songs from the playlist, you will need to create a copy of the `allSongs` array without mutating the original. This is where the `spread` operator comes in handy.

-The spread operator `...` allows you to create a new array by copying all the elements from an existing array into another array. In the example below, both, `arr1` and `arr2` have been spread into `combinedArr`:
+The spread operator (`...`) allows you to copy all elements from one array into another. It can also be used to concatenate multiple arrays into one. In the example below, both `arr1` and `arr2` have been spread into `combinedArr`:

 ```js
 const arr1 = [1, 2, 3];
@@ -19,7 +19,7 @@ const combinedArr = [...arr1, ...arr2];
 console.log(combinedArr); // Output: [1, 2, 3, 4, 5, 6]
 ```

-Inside the `userData` object create a `songs` property. For the value spread `allSongs` into an array.
+Inside the `userData` object create a `songs` property. For the value, spread `allSongs` into an array.

 # --hints--

@@ -7,7 +7,7 @@ dashedName: step-10

 # --description--

-To handle the current song's information and track the song's playback time, create a `currentSong` and `songCurrentTime` properties. Set the values to `null` and `0` respectively.
+To handle the current song's information and track its playback time, create a `currentSong` and `songCurrentTime` properties. Set the values to `null` and `0` respectively.

 # --hints--

@@ -1,8 +1,8 @@
 ---
 id: 656472ed8f552d2f2b3f7883
-title: Step 24
+title: Step 25
 challengeType: 0
-dashedName: step-24
+dashedName: step-25
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 6567055f59d39f07d1c542dc
-title: Step 18
+title: Step 19
 challengeType: 0
-dashedName: step-18
+dashedName: step-19
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65671421254eeb489875cdd8
-title: Step 48
+title: Step 49
 challengeType: 0
-dashedName: step-48
+dashedName: step-49
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65672136535209761a5cf02b
-title: Step 30
+title: Step 31
 challengeType: 0
-dashedName: step-30
+dashedName: step-31
 ---

 # --description--
@@ -1,8 +1,8 @@
 ---
 id: 65672adafbaa37a6cef886f7
-title: Step 73
+title: Step 74
 challengeType: 0
-dashedName: step-73
+dashedName: step-74
 ---

 # --description--
@@ -0,0 +1,629 @@
+---
+id: 657b2b0b6a48071a6db28e7a
+title: Step 13
+challengeType: 0
+dashedName: step-13
+---
+
+# --description--
+
+The `map()` method is used to iterate through an array and return a new array. It's helpful when you want to create a new array based on the values of an existing array. For example:
+
+```js
+const numbers = [1, 2, 3];
+const doubledNumbers = numbers.map((number) => number * 2); // doubledNumbers will be [2, 4, 6]
+```
+
+Notice that the `map()` method takes a function as an argument. This is called a <dfn>callback function</dfn>, which is a function that is passed to another function as an argument. In the example above, the callback function is `(number) => number * 2`, and it's run on each element in the `numbers` array. The `map()` method then returns a new array with the results.
+
+Pass in a callback function to the `map()` method. The callback function should take `song` as a parameter, use the arrow function syntax, and have an empty body.
+
+# --hints--
+
+The callback function of your `map()` method should use arrow function syntax.
+
+```js
+assert.match(code, /const\s+songsHTML\s*=\s*array.map\(\(?.*\)?\s*=>\s*\{\s*\}\)/)
+```
+
+Your `map()` method should have a `song` parameter in it's callback function.
+
+```js
+assert.match(code, /const\s+songsHTML\s*=\s*array.map\(\(?song\)?/)
+```
+
+# --seed--
+
+## --seed-contents--
+
+```html
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <link
+      href="https://fonts.googleapis.com/css2?family=Roboto+Mono&display=swap"
+      rel="stylesheet"
+    />
+    <link
+      href="https://fonts.googleapis.com/css2?family=Lato&family=Roboto+Mono&display=swap"
+      rel="stylesheet"
+    />
+    <link rel="stylesheet" href="styles.css" />
+    <title>
+      Learn Basic String and Array Methods by Building a Music Player App
+    </title>
+  </head>
+
+  <body>
+    <div class="container">
+      <div class="player">
+        <div class="player-bar">
+          <div class="parallel-lines">
+            <div></div>
+            <div></div>
+          </div>
+          <h1 class="fcc-title">freeCodeCamp</h1>
+          <div class="parallel-lines">
+            <div></div>
+            <div></div>
+          </div>
+        </div>
+        <div class="player-content">
+          <div id="player-album-art">
+            <img
+              src="https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/quincy-larson-album-art.jpg"
+              alt="song cover art"
+            />
+          </div>
+          <div class="player-display">
+            <div class="player-display-song-artist">
+              <p id="player-song-title"></p>
+              <p id="player-song-artist"></p>
+            </div>
+            <div class="player-buttons">
+              <button id="previous" class="previous" aria-label="Previous">
+                <svg
+                  width="24"
+                  height="19"
+                  viewBox="0 0 24 19"
+                  fill="none"
+                  xmlns="http://www.w3.org/2000/svg"
+                ><path d="M23.2248 0L7.03964 9.5L23.2248 19L23.2248 0Z" /><rect
+                    width="4.63633"
+                    height="18.5453"
+                    transform="matrix(-1 0 0 1 4.63633 0)"/></svg>
+              </button>
+              <button id="play" class="play" aria-label="Play">
+                <svg
+                  width="17"
+                  height="19"
+                  viewBox="0 0 17 19"
+                  fill="none"
+                  xmlns="http://www.w3.org/2000/svg"
+                > <path d="M0 0L16.1852 9.5L1.88952e-07 19L0 0Z" /></svg>
+              </button>
+              <button id="pause" class="pause" aria-label="Pause">
+                <svg
+                  width="17"
+                  height="19"
+                  viewBox="0 0 17 19"
+                  fill="none"
+                  xmlns="http://www.w3.org/2000/svg"
+                ><path d="M0 6.54013e-07H4.75V19H0V6.54013e-07Z" /> <path d="M11.4 0H16.15V19H11.4V0Z" /></svg>
+              </button>
+              <button id="next" class="next" aria-label="Next">
+                <svg
+                  width="24"
+                  height="19"
+                  viewBox="0 0 24 19"
+                  fill="none"
+                  xmlns="http://www.w3.org/2000/svg"
+                ><path d="M0 0L16.1852 9.5L1.88952e-07 19L0 0Z" /> <rect x="18.5885" width="4.63633" height="18.5453" /></svg>
+              </button>
+              <button id="shuffle" class="shuffle" aria-label="Shuffle">
+                <svg
+                  width="17"
+                  height="14"
+                  viewBox="0 0 17 14"
+                  fill="none"
+                  xmlns="http://www.w3.org/2000/svg"
+                ><path
+                    fill-rule="evenodd"
+                    clip-rule="evenodd"
+                    d="M12.2127 0L17 2.9219L12.0759 5.60686L12.1321 3.30594C11.9081 3.30997 11.7043 3.3165 11.528 3.326C11.3777 3.3341 11.2523 3.34411 11.1542 3.35578C11.1053 3.3616 11.0661 3.36749 11.036 3.37309C11.0211 3.37587 11.0095 3.37835 11.001 3.38041C10.9967 3.38143 10.9936 3.38227 10.9913 3.38289C10.989 3.38352 10.988 3.38385 10.9881 3.38382C10.9266 3.40381 10.7572 3.5014 10.4637 3.73265C10.1895 3.94866 9.85452 4.24234 9.47614 4.59282C8.81462 5.20556 8.03912 5.97461 7.25609 6.76752C8.03912 7.56043 8.81462 8.32948 9.47614 8.94223C9.85452 9.29271 10.1895 9.58639 10.4637 9.80239C10.7572 10.0336 10.9266 10.1312 10.9881 10.1512C10.988 10.1512 10.989 10.1515 10.9913 10.1522C10.9936 10.1528 10.9967 10.1536 11.001 10.1546C11.0095 10.1567 11.0211 10.1592 11.036 10.162C11.0661 10.1676 11.1053 10.1734 11.1542 10.1793C11.2523 10.1909 11.3777 10.2009 11.528 10.209C11.7043 10.2185 11.9081 10.2251 12.1321 10.2291L12.0759 7.92819L17 10.6131L12.2127 13.535L12.1558 11.2011C11.9071 11.197 11.677 11.1899 11.4757 11.1791C11.175 11.1629 10.8757 11.1361 10.6878 11.0751C10.4405 10.9947 10.1465 10.7892 9.86244 10.5654C9.55904 10.3263 9.20251 10.0129 8.81601 9.6549C8.14192 9.03051 7.35822 8.2533 6.57518 7.46052C6.2731 7.76927 5.9736 8.07675 5.68453 8.37353C5.24051 8.8294 4.82109 9.26001 4.45467 9.63114C4.10458 9.98574 3.79502 10.2941 3.54834 10.5285C3.42516 10.6455 3.31437 10.7473 3.22005 10.8285C3.13287 10.9035 3.03686 10.9812 2.94938 11.0324C2.46156 11.3178 1.79381 11.3751 1.32395 11.3812C1.07514 11.3845 0.852462 11.3732 0.692065 11.3611C0.611577 11.3551 0.546037 11.3488 0.499864 11.344C0.476761 11.3415 0.458455 11.3394 0.445496 11.3379L0.43012 11.336L0.425557 11.3355L0.423542 11.3352C0.423448 11.3352 0.423143 11.3352 0.485767 10.8535L0.423542 11.3352C0.157529 11.3006 -0.0304782 11.0569 0.00410824 10.7909C0.0386807 10.525 0.282182 10.3374 0.548069 10.3718C0.548087 10.3718 0.548051 10.3718 0.548069 10.3718L0.549944 10.372L0.559616 10.3732C0.568682 10.3743 0.582871 10.3759 0.60165 10.3779C0.639243 10.3818 0.695017 10.3872 0.764728 10.3924C0.90473 10.4029 1.09799 10.4127 1.31133 10.4099C1.76571 10.404 2.20705 10.3412 2.4587 10.194C2.45847 10.1941 2.4583 10.1942 2.4587 10.194C2.46075 10.1926 2.47161 10.1855 2.49271 10.1693C2.51674 10.1508 2.54777 10.1254 2.58634 10.0922C2.66358 10.0258 2.7615 9.93612 2.87917 9.82431C3.11419 9.60097 3.41488 9.30164 3.76339 8.94864C4.1317 8.57559 4.54478 8.15147 4.98424 7.70025C5.27761 7.39904 5.58273 7.08575 5.89415 6.76752C5.58272 6.44928 5.27759 6.13598 4.98421 5.83476C4.54476 5.38355 4.1317 4.95944 3.76339 4.5864C3.41488 4.2334 3.11419 3.93407 2.87917 3.71074C2.7615 3.59892 2.66358 3.50929 2.58634 3.44281C2.54777 3.40961 2.51674 3.38425 2.49271 3.36577C2.4716 3.34954 2.46099 3.34258 2.45894 3.34123C2.45868 3.34108 2.45853 3.34096 2.45894 3.34123C2.2073 3.19405 1.76572 3.13106 1.31133 3.12515C1.09799 3.12238 0.90473 3.13211 0.764728 3.14261C0.695017 3.14784 0.639243 3.15321 0.60165 3.15717C0.582871 3.15915 0.568682 3.16077 0.559616 3.16184L0.549944 3.16301L0.548391 3.1632C0.282436 3.1977 0.0386882 3.01013 0.00410824 2.74417C-0.0304782 2.47816 0.15713 2.23447 0.423143 2.19989L0.485767 2.68154C0.423143 2.19989 0.423048 2.1999 0.423143 2.19989L0.425557 2.19958L0.43012 2.199L0.445496 2.19714C0.458455 2.19561 0.476761 2.19352 0.499864 2.19109C0.546037 2.18622 0.611577 2.17995 0.692065 2.17391C0.852462 2.16188 1.07514 2.15058 1.32395 2.15381C1.79381 2.15992 2.46156 2.21726 2.94938 2.50267C3.03686 2.55385 3.13287 2.63152 3.22005 2.70655C3.31437 2.78773 3.42516 2.8895 3.54834 3.00655C3.79502 3.24097 4.10458 3.54931 4.45467 3.9039C4.82109 4.27504 5.24052 4.70565 5.68455 5.16153C5.97361 5.4583 6.2731 5.76578 6.57518 6.07452C7.35822 5.28174 8.14192 4.50454 8.81601 3.88014C9.20251 3.52214 9.55904 3.20872 9.86244 2.96964C10.1465 2.74581 10.4405 2.54035 10.6878 2.45997C10.8757 2.39892 11.175 2.37219 11.4757 2.35598C11.677 2.34514 11.9071 2.33807 12.1558 2.33396L12.2127 0Z"
+                  /></svg>
+              </button>
+            </div>
+          </div>
+        </div>
+      </div>
+      <div class="playlist">
+        <div class="playlist-bar">
+          <div class="parallel-lines">
+            <div></div>
+            <div></div>
+          </div>
+          <h2 class="playlist-title" id="playlist">Playlist</h2>
+          <div class="parallel-lines">
+            <div></div>
+            <div></div>
+          </div>
+        </div>
+        <ul id="playlist-songs"></ul>
+      </div>
+    </div>
+    <script src="script.js"></script>
+  </body>
+</html>
+```
+
+```css
+:root {
+  /* colors */
+  --primary-color: #dfdfe2;
+  --secondary-color: #ffffff;
+  --app-background-color: #4d4d62;
+  --background-color: #1b1b32;
+  --foreground-color: #3b3b4f;
+  --highlight-color: #f1be32;
+
+  /* font sizes */
+  --root-font-size: 16px;
+  font-size: var(--root-font-size);
+
+  /* font-families */
+  --font-headline: "Roboto Mono", monospace;
+  --font-family: "Lato", sans-serif;
+}
+
+*,
+*::after,
+*::before {
+  box-sizing: border-box;
+}
+
+body {
+  background-color: var(--app-background-color);
+  color: var(--primary-color);
+  font-family: var(--font-family);
+}
+
+h1 {
+  font-size: 1.125rem;
+  line-height: 1.6;
+}
+
+h2 {
+  font-size: var(--root-font-size);
+}
+
+ul {
+  margin: 0;
+}
+
+.container {
+  margin-top: 10px;
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  align-items: center;
+  row-gap: 5px;
+}
+
+.player,
+.playlist {
+  width: 450px;
+  background-color: var(--background-color);
+  border: 3px solid var(--foreground-color);
+}
+
+.player {
+  height: 260px;
+  padding: 10px;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  row-gap: 10px;
+}
+
+.player-bar,
+.playlist-bar {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 0 5px;
+  width: 100%;
+  height: 30px;
+  background-color: var(--foreground-color);
+}
+
+.parallel-lines {
+  display: flex;
+  flex-wrap: wrap;
+  row-gap: 6px;
+  padding: 0 5px;
+}
+
+.parallel-lines > div {
+  height: 2px;
+  width: 100%;
+  min-width: 75px;
+  background-color: var(--highlight-color);
+}
+
+.fcc-title,
+.playlist-title {
+  color: var(--secondary-color);
+  margin: 0 10px;
+  font-family: var(--font-headline);
+}
+
+.player-content {
+  display: flex;
+  background-color: var(--foreground-color);
+  width: 430px;
+  height: 200px;
+  column-gap: 13px;
+  align-items: center;
+  justify-content: center;
+}
+
+#player-album-art {
+  background-color: var(--secondary-color);
+  border: 6px solid var(--background-color);
+}
+
+#player-album-art img {
+  width: 150px;
+  display: block;
+}
+
+.player-display {
+  display: flex;
+  flex-direction: column;
+  row-gap: 20px;
+  padding: 14px;
+  background-color: var(--background-color);
+  height: 153px;
+  width: 226px;
+}
+
+.player-display-song-artist {
+  height: 80px;
+}
+
+.player-buttons svg {
+  fill: var(--primary-color);
+}
+
+.playing > svg {
+  fill: var(--highlight-color);
+}
+
+.player-buttons {
+  display: flex;
+  justify-content: space-around;
+}
+
+button {
+  background: transparent;
+  border: none;
+  color: var(--primary-color);
+  cursor: pointer;
+  font-size: var(--root-font-size);
+  outline-color: var(--highlight-color);
+  text-align: center;
+}
+
+.playlist-song {
+  outline-color: var(--highlight-color);
+}
+
+.playlist li:not(:last-child) {
+  border-bottom: 1px solid var(--background-color);
+}
+
+button:focus,
+.playlist-song:focus {
+  outline-style: dashed;
+  outline-width: 2px;
+}
+
+/* Playlist */
+.playlist {
+  height: auto;
+  padding: 10px;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  row-gap: 10px;
+}
+
+#playlist-songs {
+  width: 430px;
+  height: 100%;
+  background-color: var(--foreground-color);
+  display: flex;
+  flex-direction: column;
+  row-gap: 8px;
+  padding: 8px 9px;
+  visibility: visible;
+  justify-content: start;
+  list-style: none;
+}
+
+.playlist-song {
+  display: flex;
+  height: 55px;
+  justify-content: space-between;
+  align-items: center;
+  padding: 5px;
+}
+
+[aria-current="true"] {
+  background-color: var(--background-color);
+}
+
+[aria-current="true"] p {
+  color: var(--highlight-color);
+}
+
+.playlist-song-info {
+  height: 100%;
+  display: flex;
+  flex-direction: row;
+  align-items: center;
+  justify-content: space-around;
+  column-gap: 7px;
+  padding: 5px 0;
+  font-family: var(--font-family);
+}
+
+#player-song-title,
+#player-song-artist {
+  margin: 0;
+}
+
+#player-song-artist {
+  color: var(--highlight-color);
+  font-size: 0.75rem;
+}
+
+#player-song-title {
+  font-size: 1.125rem;
+}
+
+.playlist-song-title {
+  font-size: 0.85rem;
+  width: 241px;
+  text-align: left;
+}
+
+.playlist-song-artist {
+  font-size: 0.725rem;
+  width: 80px;
+}
+
+.playlist-song-duration {
+  font-size: 0.725rem;
+  margin: auto;
+  font-family: var(--font-headline);
+  width: 30px;
+}
+
+.playlist-song-delete {
+  padding: 0;
+  width: 20px;
+  height: 20px;
+}
+
+.playlist-song-delete,
+.playlist-song-delete {
+  fill: var(--foreground-color);
+}
+
+.playlist-song-delete:hover circle,
+.playlist-song-delete:focus circle {
+  fill: #ff0000;
+}
+
+@media (max-width: 700px) {
+  .player,
+  .playlist {
+    width: 300px;
+  }
+
+  .player {
+    height: 340px;
+  }
+
+  #playlist-songs {
+    height: 280px;
+    padding: 5px 6px;
+    overflow-y: scroll;
+    overflow-x: hidden;
+    scrollbar-color: var(--background-color) var(--secondary-color);
+    scrollbar-width: thin;
+  }
+
+  #playlist-songs::-webkit-scrollbar {
+    width: 5px;
+  }
+
+  #playlist-songs::-webkit-scrollbar-track {
+    background: var(--background-color);
+  }
+
+  #playlist-songs::-webkit-scrollbar-thumb {
+    background: var(--secondary-color);
+  }
+
+  h1 {
+    font-size: 0.813rem;
+  }
+
+  h2 {
+    font-size: 0.75rem;
+  }
+
+  .player-bar,
+  .playlist-bar,
+  .player-content,
+  #playlist-songs {
+    width: 280px;
+  }
+
+  .playlist-song {
+    justify-content: space-between;
+  }
+
+  .playlist-song-title {
+    width: 140px;
+  }
+
+  .playlist-song-artist {
+    width: 40px;
+  }
+
+  .playlist-song-duration > button {
+    padding: 0;
+  }
+
+  .player-content {
+    display: inline;
+    position: relative;
+    justify-items: center;
+    height: 100%;
+  }
+
+  #player-album-art {
+    z-index: -100;
+    height: 280px;
+    box-shadow: none;
+    background: #000;
+  }
+
+  #player-album-art img {
+    width: 100%;
+    opacity: 0.6;
+  }
+
+  .player-display-song-artist {
+    padding: 0 10px;
+  }
+
+  .player-display-song-artist > p {
+    white-space: pre-wrap;
+  }
+
+  .player-display {
+    position: absolute;
+    width: 100%;
+    z-index: 1000;
+    background-color: transparent;
+    top: 0;
+    height: 280px;
+    justify-content: space-between;
+    text-align: center;
+  }
+}
+```
+
+```js
+const playlistSongs = document.getElementById("playlist-songs");
+const playButton = document.getElementById("play");
+const pauseButton = document.getElementById("pause");
+const nextButton = document.getElementById("next");
+const previousButton = document.getElementById("previous");
+const shuffleButton = document.getElementById("shuffle");
+
+const allSongs = [
+  {
+    id: 0,
+    title: "Scratching The Surface",
+    artist: "Quincy Larson",
+    duration: "4:25",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/scratching-the-surface.mp3",
+  },
+  {
+    id: 1,
+    title: "Can't Stay Down",
+    artist: "Quincy Larson",
+    duration: "4:15",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/cant-stay-down.mp3",
+  },
+  {
+    id: 2,
+    title: "Still Learning",
+    artist: "Quincy Larson",
+    duration: "3:51",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/still-learning.mp3",
+  },
+  {
+    id: 3,
+    title: "Cruising for a Musing",
+    artist: "Quincy Larson",
+    duration: "3:34",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/cruising-for-a-musing.mp3",
+  },
+  {
+    id: 4,
+    title: "Never Not Favored",
+    artist: "Quincy Larson",
+    duration: "3:35",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/never-not-favored.mp3",
+  },
+  {
+    id: 5,
+    title: "From the Ground Up",
+    artist: "Quincy Larson",
+    duration: "3:12",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/from-the-ground-up.mp3",
+  },
+  {
+    id: 6,
+    title: "Walking on Air",
+    artist: "Quincy Larson",
+    duration: "3:25",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/walking-on-air.mp3",
+  },
+  {
+    id: 7,
+    title: "Can't Stop Me. Can't Even Slow Me Down.",
+    artist: "Quincy Larson",
+    duration: "3:52",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/cant-stop-me-cant-even-slow-me-down.mp3",
+  },
+  {
+    id: 8,
+    title: "The Surest Way Out is Through",
+    artist: "Quincy Larson",
+    duration: "3:10",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/the-surest-way-out-is-through.mp3",
+  },
+  {
+    id: 9,
+    title: "Chasing That Feeling",
+    artist: "Quincy Larson",
+    duration: "2:43",
+    src: "https://s3.amazonaws.com/org.freecodecamp.mp3-player-project/chasing-that-feeling.mp3",
+  },
+];
+
+const audio = new Audio();
+
+let userData = {
+  songs: [...allSongs],
+  currentSong: null,
+  songCurrentTime: 0,
+};
+
+const renderSongs = (array) => {
+--fcc-editable-region--
+  const songsHTML = array.map();
+--fcc-editable-region--
+};
+
+```