Flexbox large items

by kmouse

HTML

<div class="container">
  <div class="content-box">
    <div class="a">Title</div>
    <div class="b"></div>
    <div class="c"></div>
    <div class="d">Some text contents</div>
  </div>
</div>

CSS

body {
  background-color: black;

  width: 100%;
  height: 100%;
  color: white;

  display: flex;
  align-items: center;
  justify-content: center;
}

div.container {
  width: 1280px;
  height: 720px;
  background-color: #1f001f;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.d {
  background-color: #003f3f;
  height: 480px;
  overflow-y: scroll;
}

.content-box {
  border: 1px solid white;
  box-sizing: border-box;
  padding: 32px 20px;
  flex-grow: 1;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.content-box > * {
  /*flex-shrink: 0;*/
}

.a {
  border: 1px solid  red;
  font-size: 24px;
  font-weight: bold;
}

.b {
  border: 1px solid red;
  width: 774px;
  height: 50px;
}

.c {
  border: 1px solid red;
  width: 600px;
  height: 450px;
}