May i know how can i do that?

Tell us what’s happening:
Describe your issue in detail here.

To give the fieldset elements a bit of separation, select all but the last fieldset element, and give them a border-bottom of 3px solid #3b3b4f .
Your code so far

/* file: index.html */
<!DOCTYPE html>
<html>
 <head>
   <title>Registration Form</title>
	  <link rel="stylesheet" href="styles.css" />
 </head>
 <body>
   <h1>Registration Form</h1>
   <p>Please fill out this form with the required information</p>
   <form action='https://register-demo.freecodecamp.org'>
     <fieldset>
       <label>Enter Your First Name: <input type="text" name="first-name" required /></label>
       <label>Enter Your Last Name: <input type="text" name="last-name" required /></label>
       <label>Enter Your Email: <input type="email" name="email" required /></label>
       <label>Create a New Password: <input type="password" name="password" pattern="[a-z0-5]{8,}" required /></label>
     </fieldset>
     <fieldset>
       <label><input type="radio" name="account-type" /> Personal Account</label>
       <label><input type="radio" name="account-type" /> Business Account</label>
       <label>
         <input type="checkbox" name="terms" required /> I accept the <a href="https://www.freecodecamp.org/news/terms-of-service/">terms and conditions</a>
			  </label>
     </fieldset>
     <fieldset>
       <label>Upload a profile picture: <input type="file" name="file" /></label>
       <label>Input your age (years): <input type="number" name="age" min="13" max="120" />
			  </label>
       <label>How did you hear about us?
         <select name="referrer">
           <option value="">(select one)</option>
           <option value="1">freeCodeCamp News</option>
           <option value="2">freeCodeCamp YouTube Channel</option>
           <option value="3">freeCodeCamp Forum</option>
           <option value="4">Other</option>
         </select>
       </label>
       <label>Provide a bio:
         <textarea name="bio" rows="3" cols="30" placeholder="I like coding on the beach..."></textarea>
			  </label>
     </fieldset>
     <input type="submit" value="Submit" />
   </form>
 </body>
</html>
/* file: styles.css */
body {
 width: 100%;
 height: 100vh;
 margin: 0;
 background-color: #1b1b32;
	color: #f5f6f7;
 font-family: Tahoma;
	font-size: 16px;
}

h1, p {
 margin: 1em auto;
 text-align: center;
}

form {
 width: 60vw;
	max-width: 500px;
	min-width: 300px;
	margin: 0 auto;
}

fieldset {
 border: none;
	padding: 2rem 0;
}

fieldset{
 border-bottom:3px solid #3b3b4f;
}

label {
	display: block;
	margin: 0.5rem 0;
}

   **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.5060.53 Safari/537.36 Edg/103.0.1264.37

Challenge: Step 41

Link to the challenge:

Try to run your code, you’ll see a hint; that’s what you need to use.

hint is showing this one.
You can use the :not(:last-of-type) pseudo-class to select all but the last element.plz help me.

That’s it, that’s the selector you need to use. Here’s the breakdown:

.element selects all the instances of the element

.element:last-of-type selects only the last instance of the element

.element:not(:last-of-type) selects all instances of the element except the last one

If this all seems new to you maybe you could read or watch a refresher on pseudo-class selectors

I’m sorry, that came off wrong. It does help to understand the concept when solving the problem but to be fair these are quite complex selectors, it’s not unusual to struggle with them.