html - Fixed Header, Footer, and Sidebars with scrolling content area in center

Question

Starting with this Demo Template, I would like to create this layout:

But I have the following problems:

• The two sidebars are not contained inside the scrollable content div.
• The content div does not take a fixed size
• The scrollable content does not present a scrollbar when it overflows
• It is preferred if the browser's main scrollbar is used

Can someone help me to fix these issues?

Answer 1

Using display:grid

This uses several new features of CSS that may or may not be supported in your browser of choice. These include Grid Layout, CSS Variables, and position:sticky. CSS Variables can be worked around with static values and Grid/position:sticky can degrade gracefully with @supports.

/* Remove unnecessary margins/padding */
html, body { margin: 0; padding: 0 }

.wrapper {
  display: grid;
  /* Header and footer span the entire width, sidebars and content are fixed, with empty space on sides */
  grid-template-areas:
    "header header header header header"
    "empty_left sidebar_1 content sidebar_2 empty_right"
    "footer footer footer footer footer";
  /* Only expand middle section vertically (content and sidebars) */
  grid-template-rows: 0fr 1fr 0fr;
  /* 100% width, but static widths for content and sidebars */
  grid-template-columns: 1fr 100px 400px 100px 1fr;
  /* Force grid to be at least the height of the screen */
  min-height: 100vh;
}
.header {
  grid-area: header;

  /* Stick header to top of grid */
  position: sticky;
  top: 0;
  /* Ensure header appears on top of content/sidebars */
  z-index: 1;

  /* General appearance */
  background-color: #FCFF34;
  text-align: center;
  font-size: 1rem;
  line-height: 1.5;
  padding: 1rem;
}
/* Save header height to properly set `padding-top` and `margin-top` for sticky content */
:root {
  --header-height: calc(1rem * 1.5 + 1rem * 2);
}

.sidebar-1 {
  grid-area: sidebar_1;
}
.sidebar-2 {
  grid-area: sidebar_2;
}
.sidebar-1,
.sidebar-2 {
  display: flex;
  flex-direction: column;
  position: sticky;
  top: 0;

  /* Styling to match reference */
  background-color: #BC514F;
}

.content {
  grid-area: content;

  /* General appearance */
  background-color: #99BB5E;
}
.footer {
  grid-area: footer;

  /* Stick footer to bottom of grid */
  position: sticky;
  bottom: 0;

  /* General appearance */
  background-color: #FCFF34;
  text-align: center;
  font-size: .8rem;
  line-height: 1.5;
  padding: .5rem;
}
/* Save footer height to properly set `bottom` and `min-height` for sticky content */
:root {
  --footer-height: calc(.8rem * 1.5 + .5rem * 2);
}

.sticky-spacer {
  flex-grow: 1;
}
.sticky-content {
  position: sticky;
  bottom: var(--footer-height);
  min-height: calc(100vh - var(--footer-height));
  box-sizing: border-box;

  --padding: 10px;
  padding:
    calc(var(--header-height) + var(--padding))
    var(--padding)
    var(--padding);
  margin-top: calc(0px - var(--header-height));
}

<div class="wrapper">
<div class="header">Header (Absolute)</div>
<div class="sidebar-1">
  <div class="sticky-spacer"></div>
  <div class="sticky-content">Sidebar 1 Absolute position, Fixed width</div>
</div>
<div class="content">
  <div class="sticky-spacer"></div>
  <div class="sticky-content">
    Scrollable content<br><br>
    line 1<br><br>
    line 2<br><br>
    line 3<br><br>
    line 4<br><br>
    line 5<br><br>
    line 6<br><br>
    line 7<br><br>
    line 8<br><br>
    line 9<br><br>
    line 10<br><br>
    line 11<br><br>
    line 12<br><br>
    line 13<br><br>
    line 14<br><br>
    line 15<br><br>
    line 16<br><br>
    line 17<br><br>
    line 18<br><br>
    line 19<br><br>
    line 20
  </div>
</div>
<div class="sidebar-2">
  <div class="sticky-spacer"></div>
  <div class="sticky-content">
    Sidebar 2 Absolute position, Fixed width<br><br>
  line 1<br><br>
  line 2<br><br>
  line 3<br><br>
  line 4<br><br>
  line 5<br><br>
  line 6<br><br>
  line 7<br><br>
  line 8<br><br>
  line 9<br><br>
  line 10
  </div>
</div>
<div class="footer">Footer (Absolute)</div>
</div>