Technical documentation page

Here’s my Html for my technical doc challange.
It is not fulfilling the following user stories:

  1. Each .main-section should have an id that matches the text of its first child, having any spaces in the child’s text replaced with underscores (_) for the id’s.

  2. You should have the same number of .nav-link and .main-section elements.

  3. Each .nav-link should have text that corresponds to the header text of its related section (e.g. if you have a “Hello world” section/header, your #navbar should have a .nav-link which has the text “Hello world”).

I need assistance.

``

Technical-Documentation-Page. Js Documentation
        <li><a id="What_you_already_know" class="nav-link" href="#What_you_should_already_know">What you should already know</a>
        </li>

        <li><a id="Javascript_and_Java" class="nav-link" href="#Javascript_and_Java">Javascript and Java</a>
        </li>

        <li><a id="Hello_world" class="nav-link" href="#Hello_world">Hello world</a></li>

        <li><a id="Variables" class="nav-link" href="#Variables">Variables</a></li>

        <li><a id="Declaring_variables" class="nav-link" href="#Declaring_variables">Declaring variables</a></li>

        <li><a id="Variable_scope" class="nav-link" href="#Variable_scope">Variable scope</a></li>

        <li><a id="Global_variables" class="nav-link" href="#Global_variables">Global variables</a></li>

        <li><a id="Constant" class="nav-link" href="#Constants"> Constants</a></li>

        <li><a id="Data_types" class="nav-link" href="#Data_types"> Data types</a></li>

        <li><a id="if..._else_statements" class="nav-link" href="#if..._else_statements">if...else statements</a></li>

        <li><a id="While_statement" class="nav-link" href="#While_statement">While statement</a></li>

        <li><a id="Function_declaration" class="nav-link" href="#Function_declarations">Function declarations</a></li>

        <li><a id="Reference" class="nav-link" href="#Reference">Reference</a></li>
     </ul>
   </nav>

    <section id="Introduction" class="main-section">
      <header >Introduction</header>
      <article>
        <p>Javascript is a cross-platform,object-oriented scripting language.It is a small and lightweight language, inside a host enviroment(for example,a web browser, Javascript can be connected to the objects of its enviroment to provide programmatic controlover them.</p>
        <p>Javascript contains a stsndard library of objects, such as Array,Date, and Math,and a core set of language operators ,control structures,and statements.Core Javascript can be extended for a variesty of purposes by supplementing it with additional objects;for example:</p>
    <ul>
      <li>Client-side Javascript extends the core language by supplying objects to control a browser and its Document Object Model(DOM).For example, client-side extensions allow an application to place elements on an HTmL form and respond to user events such as mouse clicks, form input, and page navigation.
        </li>
      <li>Server-side Javascript extends the core language by supplying objects relevant to running Javascript on a server.For example, server-side extensions allow an application to communicate with a database, provide continuity of information from one invocation to another of the application, or perform file manipulations on a server.
        </li>
     </ul>     
        </article>
    </section>

    <section id="What_you_should_already_know" class="main-section">
      <header>What you should already know</header>
      <article>
        <p>This guide assumes you have the following basic background:</p>
        <ul>
          <li>A general understanding of the internet and the World Wide Web(WWW).</li>
          <li>Good working knowledge of the Hyper Text Markup Language(HTML)</li>
          <li>Some programming experience,If you are new to programming, try one of the tutorials linked on the main page about Javascript.</li>
          </ul>
      </article>
    </section>

    <section id="Javascript_and_Java" class="main-section">
      <header>Javascript and Java</header>
      <article>
        <p>Javascript and Java are similar in some ways but fundamentally different in some others.The Javascript language resembles Java but does not have Java's satic typing and strong type checking. Javascript follows most java expression syntax , naming conventions and basic control-flow constructs whic was the reason why it was renamed from Livescript to Javscript</p>
        <p>In contrast to Java's compile-time system of classes built by declarartions, Javascript supports a runtime system based ona small number of data types representing numeric,Boolean, and string values. javascript has a prototype-based object model instead of the more common class-based object model. The prototype-based model provides dynamic inheritance; that is , what is inherited can vary for individual objects. Javascript also supports functions without any special declarative requirements.Functions can be properties of objects, executing as loosely typed methods</p>
        <p>Javascript is a very free-form language compared to Java.You do not have to declare all variables ,classes, and methods. You do not have to be concerned with whether methods are public, private, or protected, and you do nto have to implement interfaces. Variables, parameters, and function return types are not explicityly typed.</p>
     </article>

    </section>
    <section id="Hello_world" class="main-section">
      <header>Hello world</header>
      <article>
        <p>To get started with Javascript, open the scratchpad and write your first "Hello world" JavaScript code:</p>
        <code>function greetMe(yourName) { alert("hello" + yourNmae); }
          greetMe("world")
        </code>
        <p>Select the code in the pad and hit Ctrl+R to watch it unfold in your browser!</p>
        </article>
    </section>

    <section id="Variables" class="main-section">
      <header>Variables</header>
      <article>
        <p>You use variables as symbolic names for values in your application. The names of variabkes, called identifiers, conform to certain rules.</p>
        <p>A Javascript identifier must start with a letter, underscore(_), or dollar sign ($);subsequent characters can also be digits (0_9). Because JavaScript is case sensitive, letters include the characters "a: through "Z" (uppercase) and the characters "a" through "z" (lowercase)</p>
        <p>You can use ISO 8859-1 Unicode letters such as 'a' and 'u' in identifiers. you can also use the Unicode escape sequence as characters in identifiers. Some examples of legal names are Numbers_hits , temp99, and _name</p>
        </article>
    </section>

    <section id="Declaring_variables" class="main-section">
    <header>Declaring variables<header>
      <article>
        <pyou can declare a variable in three ways:
        <p>With the keyword var. For example</p>
        <code>var x = 42.</code>
        <p>This syntax can be used to declare both local and global variables</p>
        <p>By simply asigning it a value. For example,</p>
        <code>x = 42</code>
        <p>This will aways declare a global variable. it generates a strict JavaScript warnimg. You shouldn't use this variant.</p>
        <p>With the word let. For example,</p>
        <code>let y = 13</code>
        <p>This syntax can be used to declare a block scope local variable. See Variable scope below.</p>
        </article>
    </section>

    <section id="Variable_scope" class="main-section">
      <header>Variable scope</header>
      <article>
        <p>When you declare a variable out of any function, it is called a globla variable, because it it available to any other code in the current document.When you declare a variable within a function, it is called a local variable, because it is available only within that function.</p>
        <p>JavaScript before ECMAScript 2015 does not have block statement scope; rather , a variable declared within a block is local to the function(or global scope) that the block resides within. For example the following code will log 5, because the scope of x is the function (or global context) within which x is declared, not the block, which in this case is an if statement.</p>
        <code>if (true) { var x = 5; } console.log(x); // 5</code>
        <p>This behavior changes, when using the let declaration introduced in ECMAScript 2015</p>
        <code>if (true) { let y = 5; } console.log(y); // Reference-error: y is not defined
        </code>
        </article>
    </section>

    <section id="Global_variables" class="main-section">
      <header>Global variables<header>
       <p>Global variables are in fact properties of the global object. In web pages the global object is window, so you can  set and access global variables using the window.variable syntax.</p>
       <p>Consequently, you can access global variables declared in one window of frame from another window or frame by specifying the window or frame name. For example, if a variable called phoneNumber is declared in a document, you can refer to this variable from an iframe as a parent.phoneNumber.</p> 
    </section>

    <section id="Constants" class="main-section">
      <header>Constants</header>
      <p>You can create a read-only, named constant with the const keyword.The syntax of a constant identifier is the same as for a variable identifier:it mst start with a letter, underscore or dollar sign and can contain alphabetic, numeric, or underscore characters</p>
      <code>const PI = 3.14</code>
      <p>A constant cannot change value through assignment or be re-declared while the script is running. it has to be initialised to a value.</p>
      <p>The Scope rules for constants are the same as those for let block scope variables. if the const keyword is ommited, the identifier is assumed to represent a variable.</p>
      <p>You cannot declare a constant with the same name as a function or variable in the same scope. For example:</p>
      <code>// THIS WILL CAUSE AN ERROR function f() {}; const f = 5; //

THIS WILL CAUSE AN ERROR ALSO function f() { const g = 5; var g; //statement }

However,object attributes are not protected, so the following statement is executed without problems.


const MY_OBJECT = {“key”: “value”}; MY_OBJECT.key = “otherValue”;

    <section id="Data_types" class="main-section">
      <header>Data types</header>
      <article>
        <p>The latest ECMAScript standard defines seven data types:</p>
      <ul>
        <li>six data types that are primitives:
         <ul>
           <li>Boolean. true and false</li>
           <li>nul. A special keyword denoting a null value. Because JavaScript is case-sensitive, null is not the same as Null,NULL,or any other variant</li>
           <li>undefined. A top-level property whose value is undefined.</li>
           <li>Number.42 or 3.14159</li>
           <li>String. "Howdy"</li>
           <li>Symbol(new in ECMAScript 2015). A data type whose instances are unique and immutable.</li>
         </ul> 

        </li>

        <li>and Object</li>
      </ul>
        <p>Although this data types are a relatively small amount, they enable you to perform useful functions with your applications.Objects and functions are the other fundamental elements in the language. You can think of objects as named containers for values, and functions as procedures that your application can perform.</p>
   </article>     
    </section>

    <section id="if..._else_statements" class="main-section">
      <header>if...else statements</header>
     <article> 
      <p>Use the if statement to execute a statement if a logical condition is true. Use the optional else clause to execute a statement if the condition is false. An if statement looks as follows:
      </p>
      <code>if (condition) {statement_1; } else { statement_2; }</code>
      <p>condition can be any expression that evaluates true or false. See Boolean for an explanation of what evaluates to true and false. If condition evaluates to true , statement_1 is executed; otherwise, statement-2 is executed. Statement_1 and statement_2 can be any statement, including further nested if statements</p>
      <p>You can also compound the statements using else if to have multiple conditions tested in sequence, as follows:</p>
      <code>if (condition_1) { statement_1; } else if (condition_2) { statement_2; } else if (condition_n) {statement_n; } else { statement_last; }
      </code>
      <p>In case of multiple conditions only the first logical condition which evaluates to true will be executed. To execute multiple statements, group them within a block statement({...}). in general, it's good practice to always use block statements, especially when nesting if statements:</p>
      <code>if (condition) { statement_1_runs_if_condition_is_true; statement_2_runs_if_condition_is_true; } else { statement_3_runs_if_condition_is_false; statement_4_runs_if_condition_is_false; }</code>
      <p>It is advisable to not use simple assignments in a conditional expression, because the assignment can be confused with equality when glancing over the code. For example, do not use the following code:</p>
      <code>if (x = y) { /* statements here */ }</code>
      <p>If you need to use an assignment in a conditional expression, a common practice is to put additional parentheses around the assignment. For example:</p>
      <code>if ((x = y)) { /* statements here */ }</code>
     </article> 
    </section>

    <section id="While_statement" class="main-section">
     <header>While statement</header>
     <article>
       <p>A while statement executes its statements as long as a specified condition evaluates to true. A while statement looks as follows:</p>
       <code>while (condition) statement</code>
       <p>if the condition becomes false, statement within the loop stops executing and control passes to the statement following the loop.</p>
       <p>The condition test occurs before statement in the poop is executed. if the condition returns true, statement is executed and the condition is tested again. if the condition returns false, execution stops and control is passed to the statement following while.</p>
       <p>To execute multiple statements, use a block statement ({...})to group those statements.</p>
       <p>Example:</p>
       <p>The following loop iterates as long as n is less than three:</p>
       <code>var n = 0; var x = 0; while (n < 3) { n++; x += n; }</code>
       <p>with each iteration, the loop increments n and adds that value to x.Therefore,x and n take on the following values:</p>
       <ul>
         <li>After the first pass:n=1 and x=1</li>
         <li>After the second pass: n=2 and x=3</li>
         <li>After the third pass:n=3 and x=6</li>
         </ul>
       <p>After completing the third pass, the condition n < 3 is no longer true, so the loop terminates. </p>
       </article>
    </section>

    <section id="Function_declarations" class="main-section">
      <header>Function declarations</header>
    <article>
      <p>A  function definition (also called a function declaration, or function statement) consists of the function keyword, followed by:</p>
      <ul>
        <li>The name function</li>
        <li>A list of arguments to the function, enclosed in parentheses and separated by comas</li>
        <li>The JavaScript statement that define the function, enclosed in curly brackets,{}.</li>
        </ul>
      <p>For exam0ple, the following code defines a simple function named square</p>
      <code>function square(number) { return number * number; }</code>  
      <p>The function square takes one argument, called number. The function consists of one statement that says to return the argument of the function(that is, number) multiplied by itself. The return statement specifies the value returned by the function.</p>
      <code>return number * number</code>
      <p>Primitive parameters (such as a number) are passed to functions by value; the value is passed to the function, but if the function changes the value of the parameter, ths change is not reflected globally or in the calling function</p>
      </article>  
    </section>

    <section id="Reference" class="main_section">
      <header>Reference</header>
      <article>
        <ul>
          <li>All the documentation in this page is taken from <a href="" target="_blank">MDN</a></li>
          </ul>
        </article>
    </section>
    
  </main>
</body>
```

Try to format your code a little bit, I think that parts of it are not formatted like code and that’s quite confusing.

Also, for certification projects, alternative would be:

to place your code on codepen
and share the link here

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Technical-Documentation-Page.</title>
    <link rel="stylesheet" href="styles.css"/>
    </head>
  <body>
    <main id="main-doc">
        <nav id="navbar">
          <header>Js Documentation</header>
          <ul>
            <li><a id="Introduction" class="nav-link" href="#Introduction">Introduction</a></li>

            <li><a id="What_you_already_know" class="nav-link" href="#What_you_should_already_know">What you should already know</a>
            </li>

            <li><a id="Javascript_and_Java" class="nav-link" href="#Javascript_and_Java">Javascript and Java</a>
            </li>

            <li><a id="Hello_world" class="nav-link" href="#Hello_world">Hello world</a></li>

            <li><a id="Variables" class="nav-link" href="#Variables">Variables</a></li>

            <li><a id="Declaring_variables" class="nav-link" href="#Declaring_variables">Declaring variables</a></li>

            <li><a id="Variable_scope" class="nav-link" href="#Variable_scope">Variable scope</a></li>

            <li><a id="Global_variables" class="nav-link" href="#Global_variables">Global variables</a></li>

            <li><a id="Constant" class="nav-link" href="#Constants"> Constants</a></li>

            <li><a id="Data_types" class="nav-link" href="#Data_types"> Data types</a></li>

            <li><a id="if..._else_statements" class="nav-link" href="#if..._else_statements">if...else statements</a></li>

            <li><a id="While_statement" class="nav-link" href="#While_statement">While statement</a></li>

            <li><a id="Function_declaration" class="nav-link" href="#Function_declarations">Function declarations</a></li>

            <li><a id="Reference" class="nav-link" href="#Reference">Reference</a></li>
         </ul>
       </nav>

        <section id="Introduction" class="main-section">
          <header >Introduction</header>
          <article>
            <p>Javascript is a cross-platform,object-oriented scripting language.It is a small and lightweight language, inside a host enviroment(for example,a web browser, Javascript can be connected to the objects of its enviroment to provide programmatic controlover them.</p>
            <p>Javascript contains a stsndard library of objects, such as Array,Date, and Math,and a core set of language operators ,control structures,and statements.Core Javascript can be extended for a variesty of purposes by supplementing it with additional objects;for example:</p>
        <ul>
          <li>Client-side Javascript extends the core language by supplying objects to control a browser and its Document Object Model(DOM).For example, client-side extensions allow an application to place elements on an HTmL form and respond to user events such as mouse clicks, form input, and page navigation.
            </li>
          <li>Server-side Javascript extends the core language by supplying objects relevant to running Javascript on a server.For example, server-side extensions allow an application to communicate with a database, provide continuity of information from one invocation to another of the application, or perform file manipulations on a server.
            </li>
         </ul>     
            </article>
        </section>

        <section id="What_you_should_already_know" class="main-section">
          <header>What you should already know</header>
          <article>
            <p>This guide assumes you have the following basic background:</p>
            <ul>
              <li>A general understanding of the internet and the World Wide Web(WWW).</li>
              <li>Good working knowledge of the Hyper Text Markup Language(HTML)</li>
              <li>Some programming experience,If you are new to programming, try one of the tutorials linked on the main page about Javascript.</li>
              </ul>
          </article>
        </section>

        <section id="Javascript_and_Java" class="main-section">
          <header>Javascript and Java</header>
          <article>
            <p>Javascript and Java are similar in some ways but fundamentally different in some others.The Javascript language resembles Java but does not have Java's satic typing and strong type checking. Javascript follows most java expression syntax , naming conventions and basic control-flow constructs whic was the reason why it was renamed from Livescript to Javscript</p>
            <p>In contrast to Java's compile-time system of classes built by declarartions, Javascript supports a runtime system based ona small number of data types representing numeric,Boolean, and string values. javascript has a prototype-based object model instead of the more common class-based object model. The prototype-based model provides dynamic inheritance; that is , what is inherited can vary for individual objects. Javascript also supports functions without any special declarative requirements.Functions can be properties of objects, executing as loosely typed methods</p>
            <p>Javascript is a very free-form language compared to Java.You do not have to declare all variables ,classes, and methods. You do not have to be concerned with whether methods are public, private, or protected, and you do nto have to implement interfaces. Variables, parameters, and function return types are not explicityly typed.</p>
         </article>

        </section>
        <section id="Hello_world" class="main-section">
          <header>Hello world</header>
          <article>
            <p>To get started with Javascript, open the scratchpad and write your first "Hello world" JavaScript code:</p>
            <code>function greetMe(yourName) { alert("hello" + yourNmae); }
              greetMe("world")
            </code>
            <p>Select the code in the pad and hit Ctrl+R to watch it unfold in your browser!</p>
            </article>
        </section>

        <section id="Variables" class="main-section">
          <header>Variables</header>
          <article>
            <p>You use variables as symbolic names for values in your application. The names of variabkes, called identifiers, conform to certain rules.</p>
            <p>A Javascript identifier must start with a letter, underscore(_), or dollar sign ($);subsequent characters can also be digits (0_9). Because JavaScript is case sensitive, letters include the characters "a: through "Z" (uppercase) and the characters "a" through "z" (lowercase)</p>
            <p>You can use ISO 8859-1 Unicode letters such as 'a' and 'u' in identifiers. you can also use the Unicode escape sequence as characters in identifiers. Some examples of legal names are Numbers_hits , temp99, and _name</p>
            </article>
        </section>

        <section id="Declaring_variables" class="main-section">
        <header>Declaring variables</header>
          <article>
            you can declare a variable in three ways:
            <p>With the keyword var. For example</p>
            <code>var x = 42.</code>
            <p>This syntax can be used to declare both local and global variables</p>
            <p>By simply asigning it a value. For example,</p>
            <code>x = 42</code>
            <p>This will aways declare a global variable. it generates a strict JavaScript warnimg. You shouldn't use this variant.</p>
            <p>With the word let. For example,</p>
            <code>let y = 13</code>
            <p>This syntax can be used to declare a block scope local variable. See Variable scope below.</p>
            </article>
        </section>

        <section id="Variable_scope" class="main-section">
          <header>Variable scope</header>
          <article>
            <p>When you declare a variable out of any function, it is called a globla variable, because it it available to any other code in the current document.When you declare a variable within a funtion, it is called a local variable, because it is available only within that function.</p>
            <p>JavaScript before ECMAScript 2015 does not have block statemnt scope; rathe , a variable declared within a block is locaal to the funtion(or globla scope) that the block resides within. For example the follwing code will log 5, because the scope of x is the function (or global context) within which x is declared, not the block, which in this case is an if statement.</p>
            <code>if (true) { var x = 5; } console.log(x); // 5</code>
            <p>This behaviour changes, when using the let declaration introduced in ECMAScript 2015</p>
            <code>if (true) { let y = 5; } console.log(y); // ReferenceError: y is not defined
            </code>
            </article>
        </section>

        <section id="Global_variables" class="main-section">
          <header>Global variables</header>
           <p>Global variables are in fact properties of the global object. In web pages the globla object is window, so youcan  set and access global variables using the window.variable syntax.</p>
           <p>Consequently, you can access global variables declared in one window of frame from another window or frame by specifying the window or freme name. For example, if a variable called phoneNumber is declared in a document, you can refer to this variable from an iframe as a parent.phoneNumber.</p> 
        </section>

        <section id="Constants" class="main-section">
          <header>Constants</header>
          <p>You can create a read-only, named constant with the const keyword.The syntax of a constant identifier is the same as for a variable identifier:it mst start with a letter, underscore or dollar sign and can contain alphabetic, numeric, or underscore characters</p>
          <code>const PI = 3.14</code>
          <p>A constant cannot change value through assignment or be re-declared while the script is running. it has to be initialised to a value.</p>
          <p>The Scope rules for constants are the same as those for let block scope variables. if the const keyword is ommited, the identifier is assumed to represent a variable.</p>
          <p>You cannot declare a constant with the same name as a function or variable in the same scope. For example:</p>
          <code>// THIS WILL CAUSE AN ERROR function f() {}; const f = 5; //
 THIS WILL CAUSE AN ERROR ALSO function f() { const g = 5; var g; //statement }           
          </code>
          <p>However,object attributes are not protected, so the following statement is executed without problems.</p>
          <code>const MY_OBJECT = {"key": "value"}; MY_OBJECT.key = "otherValue";</code>
          </section> 

        <section id="Data_types" class="main-section">
          <header>Data types</header>
          <article>
            <p>The latest ECMAScript standard defines seven data types:</p>
          <ul>
            <li>six data types that are primitives:
             <ul>
               <li>Boolean. true and false</li>
               <li>nul. A special keyword denoting a null value. Because JavaScript is case-sensitive, null is not the same as Null,NULL,or any other variant</li>
               <li>undefined. A top-level property whose value is undefined.</li>
               <li>Number.42 or 3.14159</li>
               <li>String. "Howdy"</li>
               <li>Symbol(new in ECMAScript 2015). A data type whose instances are unique and immutable.</li>
             </ul> 

            </li>

            <li>and Object</li>
          </ul>
            <p>Although this data types are a relatively small amount, they enable you to perform useful fun ctions with your applications.Objects and functions are the other fundamental elements in the language. You can think of objects as named containers for values, and functions as procedures that your application can perform.</p>
       </article>     
        </section>

        <section id="if..._else_statements" class="main-section">
          <header>if...else statements</header>
         <article> 
          <p>Use the if statement to execute a statement if a logical condition is true. Use the optional else clause to execute a statemnt if the condition is false. An if statement looks as follows:
          </p>
          <code>if (condition) {statement_1; } else { statement_2; }</code>
          <p>condition can be any expression thta evaluates true or false. See Boolean for an explanation of what evaluates to true and false. If condition evaluates to true , statement_1 is executed; otherwise, statement-2 is executed. Statement_1 and statement_2 can be any statement, includimg further nested if statements</p>
          <p>You can also compound the ststements using else if to have multiple conditions tested in sequence, as follows:</p>
          <code>if (condition_1) { statement_1; } else if (condition_2) { statement_2; } else if (condition_n) {statement_n; } else { statement_last; }
          </code>
          <p>In case of multiple conditions only the first logical condition which evaluates to true will be executed. To execute multiple statements, group them within a block statement({...}). in general, it's good practise to always use block statements, especially when nesting if statements:</p>
          <code>if (condition) { statement_1_runs_if_condition_is_true; statement_2_runs_if_condition_is_true; } else { statement_3_runs_if_condition_is_false; statement_4_runs_if_condition_is_false; }</code>
          <p>It is advisable to not use simple assignments in a conditional expression, because the assignment can be confused with equality when glancing over the code. For example, do not use the following code:</p>
          <code>if (x = y) { /* statements here */ }</code>
          <p>If you need to use an assignment in a conditional expression, a common practice is to put additional parentheses around the assignment. For example:</p>
          <code>if ((x = y)) { /* statements here */ }</code>
         </article> 
        </section>

        <section id="While_statement" class="main-section">
         <header>While statement</header>
         <article>
           <p>A while statement executes its statements as long as a specofied condition evaluates to true. A while statement looks as follows:</p>
           <code>while (condition) statement</code>
           <p>if the condition becomes false, statement within the loop stops executing and control passes to the statement following the loop.</p>
           <p>The condition test occurs before statement in the poop is executed. if the conddition returns true, statemnt is executed and the condition is tested again. if the condition returns false, execution stops and control is passed to the statement following while.</p>
           <p>To execute multiple statements, use a block statement ({...})to group those statements.</p>
           <p>Example:</p>
           <p>The following loop iterates as long as n is less than three:</p>
           <code>var n = 0; var x = 0; while (n < 3) { n++; x += n; }</code>
           <p>with each iteration, the loop increments n and adds that value to x.Therefore,x and n take on the following values:</p>
           <ul>
             <li>After the first pass:n=1 and x=1</li>
             <li>After the second pass: n=2 and x=3</li>
             <li>After the third pass:n=3 and x=6</li>
             </ul>
           <p>After completing the third pass, the condition n < 3 is no longer true, so the loop terminates. </p>
           </article>
        </section>

        <section id="Function_declarations" class="main-section">
          <header>Funtion declarations</header>
        <article>
          <p>A  function defination (also called a function declaration, or function statement) consists of the funktion keyword, followed by:</p>
          <ul>
            <li>The name function</li>
            <li>A list of arguments to the function, enclosed in parentheses and seperated by comas</li>
            <li>The Javascript statement that define the function, enclosed in curley brackets,{}.</li>
            </ul>
          <p>For exam0ple, the following code defines a simple function named square</p>
          <code>fuction square(number) { return number * number; }</code>  
          <p>The function square takes one argurement, called number. The function consists of one statement that syas to return the argurement of the function(that is, number) multiplied by itself. The return statement specifies the value returned by the function.</p>
          <code>return number * number</code>
          <p>Primitive parameters (such as a number) are passed to functions by value; the value is passed to the function, but if the function changes the value of the parameter, ths change is not reflected globally or in the calling function</p>
          </article>  
        </section>

        <section id="Reference" class="main_section">
          <header>Reference</header>
          <article>
            <ul>
              <li>All the documentation in this page is taken from <a href="" target="_blank">MDN</a></li>
              </ul>
            </article>
        </section>
        
      </main>
    </body>
  </html>

I have formatted my code as requested

It’s alot of code, I am not sure if I have time for all of it, so I will be pointing out issyes one by one.

I think

these two are the problem - each lower space should have corresponding space, right?

I am confused by this one. As far as I figured you have 14 navlinks and 14 sections. Not sure why it’s the issue

And one more thing. Why do you need id-s for your nav-links?
I think id-s for is required for sections, not nav-links.

That may be the issue. Id-s should be unique.

But bunch of your nav-links and sections have the same id.

General advice: run your code through validator: it should give you more ideas what needs to be fixed.

the user stories said we should replace the space with underscores, I will try and rectify to see if there shall be any changes

the same number of .nav-link and .main-section part has really given me a headache.

i will remove the Ids from the .nav-link