Flexbox avoid growing column when content overflows

HTML

<div class="top">
  <div class="firstcol">
    <div class="header">header</div>
    <div class="main">
      <div class="content">content</div>
    </div>
    <div class="footer">
      <code>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</code>
    </div>
  </div>
  <div class="secondcol">
    <div class="othercontent">fixed</div>
  </div>
</div>

SCSS

body,
html {
  height: 100%;
  display: flex;
  flex-direction: column;
  flex: 1;
  padding: 0;
  margin: 0;
}

.top {
  border: 2px solid lime;
  display: flex;
  flex: 1;
  .firstcol {
    border: 1px solid red;
    display: flex;
    flex-direction: column;
    overflow: auto;
    .header {
      border: 1px solid yellow;
    }
    .main {
      border: 1px solid navy;
      flex: 1;
      padding: 1rem 2rem;
      overflow: auto;
      .content {
        border: 2px solid maroon;
        width: 1000px;
      }
    }
    .footer {
      border: 1px solid magenta;
    }
  }
  .secondcol {
    border: 1px solid red;
    .othercontent {
      border: 1px solid yellow;
      width: 350px;
    }
  }
}