문제

풀이
<div class="container">
<div class="grid-box">
<div class="top-left"></div>
<div class="bottom-right"></div>
</div>
</div>
* {
box-sizing: border-box;
margin: 0;
}
.container {
display: flex;
justify-content: center;
align-items: center;
width: 100vw;
height: 100vh;
background: #FEFAED;
}
.grid-box {
display: grid;
grid-template-columns: 1fr 1fr 1fr 1fr;
grid-template-rows: 1fr 1fr;
width: 240px;
height: 180px;
background: #F9D9BF;
}
.top-left {
grid-column: 1;
grid-row: 1;
background: #C99F96;
}
.bottom-right {
grid-column: 4;
grid-row: 2;
background: #C99F96;
}