.grid {
    display: grid;
    grid-template-columns: repeat(3, 100px);
    grid-template-rows: repeat(3, 100px);
    gap: 5px;
    margin: 50px auto;
}

.square {
    width: 100px;
    height: 100px;
    border: 1px solid #000;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.square[data-color="red"] .triangle { border-bottom: 60px solid red; }
.square[data-color="blue"] .triangle { border-bottom: 60px solid blue; }
.square[data-color="green"] .triangle { border-bottom: 60px solid green; }
.square[data-color="yellow"] .triangle { border-bottom: 60px solid yellow; }
.square[data-color="orange"] .triangle { border-bottom: 60px solid orange; }
.square[data-color="purple"] .triangle { border-bottom: 60px solid purple; }
.square[data-color="pink"] .triangle { border-bottom: 60px solid pink; }
.square[data-color="cyan"] .triangle { border-bottom: 60px solid cyan; }
.square[data-color="grey"] .triangle { border-bottom: 60px solid grey; }

.triangle {
    width: 0;
    height: 0;
    border-left: 30px solid transparent;
    border-right: 30px solid transparent;
    border-bottom: 60px solid black;
    position: absolute;
}

.square.drop-target {
    border: 2px dashed black;
}