How to stretch div to full height with flex - html

Question

How do I stretch the divs with a yellow background to full height? It should cover up the green but it is not working. I tried adding height: 100% on it but then it adds up the height from the search bar?
https://jsfiddle.net/nuy20j1h/
.block {
width: 80%;
margin: 0 auto;
display: flex;
flex-wrap: wrap;
}
.sidebar {
height: 600px;
width: 25%;
background: red;
}
.home {
display: flex;
flex-wrap: wrap;
align-items: flex-start;
width: 75%;
background: green;
}
.search-bar {
width: 100%;
padding: 25px;
background: blue;
}
.content-wrap {
display: flex;
flex-wrap: wrap;
width: 100%;
align-items: flex-stretch;
}
.content,
.single {
width: 50%;
background: yellow;
}
<div class="block">
<div class="sidebar">sidebar</div>
<div class="home">
<div class="search-bar">search bar</div>
<div class="content-wrap">
<div class="content">lorem ipsum</div>
<div class="single">test</div>
</div>
</div>
</div>

Answer 1

First you should add a style reset, I'm using this now * {} as you can se below. The trick here is to run flex-direction: column; on .home and you can tell .content-wrap to take up the rest of that space after the search with flex-grow: 1;
box-sizing: border-box; is, if you add let's say width: 200px; to a element, and add padding: 20px;, the element will stay 200px with the padding included. If you don't have that, it will take up 200px + 40px.
if you want the fiddle, here it is
* {
padding: 0;
margin: 0;
box-sizing: border-box;
}
.block {
width: 80%;
margin: 0 auto;
display: flex;
flex-wrap: wrap;
}
.sidebar {
height: 600px;
width: 25%;
background: red;
}
.home {
display: flex;
flex-direction: column;
flex-wrap: wrap;
align-items: flex-start;
width: 75%;
background: green;
}
.search-bar {
width: 100%;
padding: 25px;
background: blue;
}
.content-wrap {
display: flex;
flex-grow: 1;
flex-wrap: wrap;
width: 100%;
align-items: flex-stretch;
}
.content,
.single {
width: 50%;
background: yellow;
}
<div class="block">
<div class="sidebar">sidebar</div>
<div class="home">
<div class="search-bar">search bar</div>
<div class="content-wrap">
<div class="content">lorem ipsum</div>
<div class="single">test</div>
</div>
</div>
</div>

Answer 2

As mentioned in other answers, there is one main issue here:
flex-direction: column;, which I added to home, to enable the usage of flex properties instead of height, to make the .content-wrap fill the available space left in home
That will make the .search-bar and .content-wrap stack vertical, and enable the use of flex: 1 on .content-wrap, which will make it fill the remaining space/height.
So even if you got answers already, and since there are some properties with wrong value, or not needed, I decided to post an answer to clarify the changes made.
See my notes made in the CSS for further clarifications and what I changed.
Stack snippet
.block {
width: 80%;
margin: 0 auto;
display: flex;
flex-wrap: wrap;
}
.sidebar {
height: 600px;
width: 25%;
background: red;
}
.home {
display: flex;
flex-direction: column; /* added */
/*flex-wrap: wrap; removed, not needed */
/*align-items: flex-start; removed, items should fill parent's,
in this changed case, width */
width: 75%;
background: green;
}
.search-bar {
/*width: 100%; not needed, default for column
item is to fill parent width as
its "align-items" is "stretch" */
padding: 25px;
background: blue;
}
.content-wrap {
flex: 1; /* added, take the remaining space left
left of its parent (height in this case) */
display: flex;
flex-wrap: wrap;
/*width: 100%; not needed, default for column
item is to fill parent width as
its "align-items" is "stretch" */
/*align-items: flex-stretch; wrong value, should be "stretch",
though since that is the default,
it is not needed */
}
.content,
.single {
width: 50%;
background: yellow;
}
<div class="block">
<div class="sidebar">sidebar</div>
<div class="home">
<div class="search-bar">search bar</div>
<div class="content-wrap">
<div class="content">lorem ipsum</div>
<div class="single">test</div>
</div>
</div>
</div>

Answer 3

flex-direction: column; is your friend. Here is a reworked fiddle of your code: https://jsfiddle.net/vsjktmms/1/
Using the same HTML structure you provided:
.block {
display: flex;
width: 80%;
margin: 0 auto;
background-color: gray;
align-items: stretch;
}
.sidebar {
width: 25%;
height: 600px;
background-color: red;
}
.home {
display: flex;
flex-direction: column;
align-items: stretch;
width: 75%;
background-color: green;
}
.search-bar {
padding: 25px;
background-color: blue;
}
.content-wrap {
flex: 1 1 auto;
display: flex;
flex-wrap: wrap;
width: 100%;
background-color: pink;
}
.content,
.single {
width: 50%;
background: yellow;
}