-1

I've heard that using 100vh will make an element take up the whole browser window. That's true. 100vh does not make the element take up the entire page though. Scroll bars can interfere with this.

Example:

#container {
  display: flex;
}

#a {
  height: 100vh;
  background-color: lightblue;
  flex: 1;
}

#b {
  flex: 2;
  word-wrap: break-word;
  background-color: lightgray;
}

body {
  margin: 0;
}
<div id="container">
  <div id="a"></div>
  <div id="b">As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long.</div>
</div>

How can I make sure that the background color stays the same for the entire page, not just the viewable part at the start?

Bennett
  • 1,007
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2 Answers2

1

Since your text is contained inside of your div, there is no need to specify a height - It will be as large as its content.

#a {
  word-wrap: break-word;
  background-color: lightblue;
}

body {
  margin: 0;
}
<div id="a">As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. </div>

Edit

What you want is (as far i know) not possible. What you can do is color the background and use a as a placeholder. I'm not sure if this solves your problem, but thats the only solution I can think of.

#container {
  display: flex;
  background-color: lightblue;
}

#a {
  flex: 1;
}

#b {
  flex: 2;
  word-wrap: break-word;
  background-color: lightgray;
}

body {
  margin: 0;
}
<div id="container">
  <div id="a"></div>
  <div id="b">As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long. As you can see, this text is very long.</div>
</div>
NyxCode
  • 584
  • 1
  • 4
  • 13
0

Easy just make it 100% or don't specify a height.

#a {
  height: 100%;
  word-wrap: break-word;
  background-color: lightblue;
}

body {
  margin: 0;
}
<div id="a">As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. As you can see, this <code>div</code> is very large and will run off the page. Scroll down to see that the background color does not apply further down on the page. </div>
Daniel A. White
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