You could use this sort of thing (margin-top) to move the content and right closer to the header. If this alters the view on mobile and makes it messy you will need to create 2 views depending on device and use different css values for different devices.
.wrapper {
border: 1px solid red;
display: grid;
grid-template-columns: 1fr 2fr 1fr;
grid-template-areas:
"aside header header"
"left content right";
grid-gap: 15px;
}
.header, .aside, .left, .content, .right {
border: 1px solid black;
padding: 10px;
}
.header {
grid-area: header;
height: 30px; /* in real case it's responsive height */
}
.aside {
grid-area: aside;
height: 80px; /* in real case it's responsive height */
}
.left {
grid-area: left;
}
.content {
grid-area: content;
background: yellow;
margin-top: -50px;
}
.right {
grid-area: right;
background: yellow;
margin-top: -50px;
}
.left, .content, .right {
height: 100px; /* in real case it's responsive height */
}