How to make CSS Grid items take up remaining space?

I have a card built with CSS Grid layout. There might be an image to the left, some text to the right top and maybe a button or a link at the right bottom.

In the code below, how can I make the green area take up as much space as possible and at the same time make the blue area take up as little space as possible?

The green should push the blue area down as far as possible.

https://jsfiddle.net/9nxpvs5m/

.grid {
  display: grid;
  grid-template-columns: 1fr 3fr;
  grid-template-areas:
    "one two"
    "one three"
}

.one {
  background: red;
  grid-area: one;
  padding: 50px 0;
}

.two {
  background: green;
  grid-area: two;
}

.three {
  background: blue;
  grid-area: three;
}

<div class="grid">
  <div class="one">
    One
  </div>
  <div class="two">
    Two
  </div>
  <div class="three">
    Three
  </div>
</div>

Adding grid-template-rows: 1fr min-content; to your .grid will get you exactly what you're after :).

.grid {
  display: grid;
  grid-template-columns: 1fr 3fr;
  grid-template-rows: 1fr min-content;
  grid-template-areas:
    "one two"
    "one three"
}

.one {
  background: red;
  grid-area: one;
  padding: 50px 0;
}

.two {
  background: green;
  grid-area: two;
}

.three {
  background: blue;
  grid-area: three;
}

<div class="grid">
  <div class="one">
    One
  </div>
  <div class="two">
    Two
  </div>
  <div class="three">
    Three
  </div>
</div>

Jens edits: For better browser support this can be used instead: grid-template-rows: 1fr auto;, at least in this exact case.

A grid is a series of intersecting rows and columns.

You want the two items in the second column to automatically adjust their row height based on their content height.

That's not how a grid works. Such changes to the row height in the second column would also affect the first column.

If you must use CSS Grid, then what I would do is give the container, let's say, 12 rows, then have items span rows as necessary.

.grid {
  display: grid;
  grid-template-columns: 1fr 3fr;
  grid-template-rows: repeat(12, 15px);
}

.one {
  grid-row: 1 / -1;
  background: red;
}

.two {
  grid-row: span 10;
  background: lightgreen;
}

.three {
  grid-row: span 2;
  background: aqua;
}

.grid > div {
  display: flex;
  align-items: center;
  justify-content: center;
}

<div class="grid">
  <div class="one">One</div>
  <div class="two">Two</div>
  <div class="three">Three</div>
</div>

Otherwise, you can try a flexbox solution.

.grid {
  display: flex;
  flex-flow: column wrap;
  height: 200px;
}

.one {
  flex: 0 0 100%;
  width: 30%;
  background: red;
}

.two {
  flex: 1 0 1px;
  width: 70%;
  background: lightgreen;
}

.three {
  background: aqua;
}

.grid>div {
  display: flex;
  align-items: center;
  justify-content: center;
}

<div class="grid">
  <div class="one">One</div>
  <div class="two">Two</div>
  <div class="three">Three</div>
</div>

When using grid, and you have grid template area used, and by chance you gave a particular area a width, you are left with a space grid does automatically. In this situation, let grid-template-columns be either min-content or max-content, so that it adjusts its position automatically.

A possible approach might be grouping two and three together, and using flexbox:

.grid {
  display: grid;
  grid-template-columns: 1fr 3fr;
  grid-template-areas: "one two"
}

.one {
  background: red;
  grid-area: one;
  padding: 50px 0;
}

.wrap {
  grid-area: two;
  display: flex;
  flex-direction: column;
}

.two {
  background: green;
  flex: 1;
}

.three {
  background: blue;
}

<div class="grid">
  <div class="one">
    One
  </div>
  <div class="wrap">

    <div class="two">
      Two
    </div>
    <div class="three">
      Three
    </div>
  </div>
</div>

Definitely not the most elegant solution and probably not best practice, but you could always add more lines of

"one two"

before the part where you have

"one three"

so it ends up looking like

.grid {
  display: grid;
  grid-template-columns: 1fr 3fr;
  grid-template-areas:
    "one two"
    "one two"
    "one two"
    "one three"
}

Again, pretty sure this is just a work around and there's better solutions out there... But this does work, to be fair.

Just use width: 100% and height: 100% in the CSS class of the item you want to fill the grid. Join a max-width property and a max-height property if you don't want a grid item inside a grid container to grow more than some size.