Background overlapping another

Html:

<!DOCTYPE html>
  <html lang="en">
    <head>
      <title>PROFILE PICKER</title>
      <meta charset="UTF-8" />
      <meta http-equiv="X-UA-Compatible" content="IE=edge" />
      <meta name="viewport" content="width=device-width, initial-scale=1.0" />
      <link rel="stylesheet" type="text/css" href="index.css" />
    </head>
    <body>
      <div class="container">
        <div id="content_box" class="content">
          <div id="profiles" class="profiles"></div>
          <div class="slider">
            <input
              type="range"
              min="0"
              max="100"
              value="50"
              class="slider"
              id="mySlider"
            />
          </div>
        </div>
      </div>
      <script src="index.js"></script>
    </body>
  </html>

Css:

body {
    margin: 0;
  }

  div.container {
    height: 100vh;
    width: 100vw;
    background-color: #1f1f21;
    background-size: cover;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
  }

  div.content {
    width: 90%;
    height: 80%;
    display: flex;  
    align-items: center;
    flex-direction: column;
    justify-content: center;
    border-radius: 47px;
    background: #262c30;
    box-shadow: inset 5px 5px 12px #0f1213, inset -5px -5px 12px #3d464d;
  }

  div.profiles {
    height: 60%;
    width: 90%;
    display: flex;
    gap: 10%;
    padding-left: 2%;
    overflow: hidden;
    background-color: transparent;
  }

  div.user_card {
    border-radius: 50px;
    border-radius: 47px;
    border-radius: 47px;
    background: linear-gradient(145deg, #3e3f40, #343536);
    box-shadow: 20px 20px 40px #232425, -20px -20px 40px #515253;
    height: 70%;
    min-width: 30%;
  }

Js:

const addUser = (userJson) => {

    const userImgUrl = userJson.picture.large;

    const container = document.querySelector("#profiles");

    const newUserCard = document.createElement("div");
    const newUserPhoto = document.createElement("img");

    newUserPhoto.src = userImgUrl;
    newUserPhoto.style.borderRadius = "50%";
    newUserCard.appendChild(newUserPhoto);
    newUserCard.classList.add("user_card");
    newUserCard.style.position = 'relative';
    newUserCard.style.zIndex = '1';
    //newUserCard.innerHTML = '<img src="' + userImgUrl + '">'//JSON.stringify(userJson, null, 2);

    container.appendChild(newUserCard)

  }

  //leggiamo un file json
  fetch("https://randomuser.me/api/?results=5")
    .then(function (data) {
      return data.json();
    }).then(function (json) {
      for (let index = 0; index < json.results.length; index++) {
        addUser(json.results[index])
      }

    })

    //leggiamo un file di testo
  /*
  fetch("sample.csv")
    .then(function (data) {
    return data.text();
  }).then(function (txt) {
    //console.log(txt);
  })
  */

The problem is that the background of the profiles overlaps the content, and makes it look awful. I want to avoid that, also if you have any advices or maybe changes regarding the color or anything in general about the program, which I want to remember should be in neumorphism style, please write them down. Thank you in advance