.main-container {
    position: relative;
    border: 1px solid #d3d3d3;
    border-radius: .5rem;
    width: fit-content;
}

.line-wrapper {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    z-index: -1;
}

.line-wrapper svg line {
    stroke: var(--vertex-line);
}

.matrix {
    display: flex;
    flex-direction: column;
    user-select: none;
    gap: var(--gaps);
    position: relative;
}

.matrix .row {
    gap: var(--gaps);
    display: flex;
    align-items: baseline;
}

.matrix .row .vertex-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    width: var(--box-size);
    height: var(--box-size);
    cursor: pointer;
    position: relative;
}

.matrix .row .vertex-wrapper:after {
    content: "";
    position: absolute;
    left: 0;
    margin: auto;
    top: 0;
    bottom: 0;
    right: 0;
    width: 80%;
    height: 80%;
    border-radius: 50%;
    transition: .3s;
}

.matrix .row .vertex-wrapper.vertex--taken:after {
    background-color: var(--vertex-around-layer);
}

.matrix .row .vertex-wrapper .vertex {
    height: 1rem;
    width: 1rem;
    border-radius: 50%;
    background-color: var(--vertex-point);
}