box with a title bar completely flushed to the top

Question

I need to create a box with contents inside it. I tried creating the box this way, but it is not quiet what I need:

.main-box {
    border-radius: 25px;
    border: 2px solid #000;
    padding: 20px;
    width: 70%;
    margin-left: 20%;
}

.box-title {
    background-color: #5b5b39;
    padding: 5px;
    color: #fff;
    font-weight: bold;
}

.box-content {
    padding-left: 10px;
    padding-right: 10px;
}

this is how it looks with the above style sheet:

I am asked to create something like this:

I don't want any space between the border and title and the title bar should completely flush the top of the box.

Answer 1

.box {
  border: 1px solid black;
  border-radius: 10px;
}

.header-wrapper {
  border: 1px solid black;
  background-color: lightblue;
  border-radius: 10px 10px 0 0;
  padding-left: 10px;
}

<div class="box">
  <div class="header-wrapper">
    <h2>Order Details</h2>
  </div>
  <div class="content">
    <ul>
      <li>item a</li>
      <li>item a</li>
      <li>item a</li>
    </ul>
  </div>
</div>