Issue with hover boxes for navbar links

I'm pretty new to web development.

I created a navbar using Bootstrap and added a :hover to the links. I also gave the hover box a color and made the corners round.

When I hover over the link, the box turns round (as intended). The issue is when I hover off the link, it turns back to a box. I tried to looking for an answer but had no luck.

I just want the containers to be the same size for each link and to stay round when hovering on and off the link.

I will try to add my code so you all can see what I'm working with.

Here is my HTML code:

<body>
  <!-- Navbar -->
    <nav class="navbar navbar-expand-lg py-4 navbar-dark" style="background-color: #000000;">
        <div class="container-fluid">
          <a class="navbar-brand mb-0 h1 text-white fs-1 px-4" href="#">Name</a>
          <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNavAltMarkup" aria-controls="navbarNavAltMarkup" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
          </button>
          <div class="collapse navbar-collapse" id="navbarNavAltMarkup">
            <div class="navbar-nav ms-auto px-4">
              <a class="nav-link active text-light fs-5 mx-2 nav-active" aria-current="page" href="#">Home</a>
              <a class="nav-link text-secondary fs-5 mx-3" href="#">Link 1</a>
              <a class="nav-link text-secondary fs-5 mx-3" href="#">Link 2</a>
              <a class="nav-link text-secondary fs-5 mx-3" href="#">Link 3</a>
              <a class="nav-link text-secondary fs-5 mx-3" href="#">Link 4</a>
            </div>
          </div>
        </div>
      </nav>

Here is my CSS code:

body {
    background-color: #252525;
}

.nav-link:hover {
    color: white;
    background-color: #48e0e4;
    border-radius: 30px;
    transition: 0.5s;
}

.nav-active {
    color: white;
    background-color: #48e0e4;
    border-radius: 30px;
    
}

Here is a link to the codepen if you need: https://codepen.io/sevilu6/pen/gOmPoZr