how to deal with grid overflow?

I created a codepen to illustrate the issue I'm facing right now https://codepen.io/marcdaframe/pen/qeBWNd

<div>
 123 abc
  <div class="container">
<div class="wrapper">
   <div>One</div>
   <div>Two</div>
   <div>Three</div>
   <div>Four</div>
   <div>Five</div>
   <div>Six</div>
   <div>Seven</div>
   <div>Eight</div>
  </div></div>
Hello World
</div>

* {box-sizing: border-box;}
.container{
  height: 25%;
  overflow-y: scroll;
}
.wrapper {
    border: 2px solid #f76707;
    border-radius: 5px;
    background-color: #fff4e6;
}

.wrapper > div {
    border: 2px solid #ffa94d;
    border-radius: 5px;
    background-color: #ffd8a8;
    padding: 1em;
    color: #d9480f;
}
.wrapper {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-gap: 10px;
  grid-auto-rows: 100px 200px;
}

I have a container which has a height defined in percents (it does work with absolute values set, but I am unable to use absolute values or vh) that the grid will be in a div 25% tall and any overflow should scroll, but the grid within the div doesn't respect that.

Solution

When you are using height:25%, you need to define 25% of what. So effectively for 25% to work, you need to give 100% height to all the parent containers till body and html.

Effectively the extra styles needed for your 25% to work are:

html,body {
   height:100%;
}
body > div {
  height:100%;
}

Note : The above div style is needed for only the parent div of "container" div. Hope it helps you to understand the issue.