.gac-board-app {
    max-width: 860px;
    margin: 24px 0;
}

.gac-board-toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    align-items: center;
    margin-bottom: 12px;
}

.gac-board-group {
    display: flex;
    gap: 6px;
}

.gac-board-toolbar button {
    border: 1px solid #b8b8b8;
    background: #fff;
    color: #111;
    padding: 8px 12px;
    font: inherit;
    font-weight: 700;
    cursor: pointer;
}

.gac-board-toolbar button.is-active {
    background: #111;
    border-color: #111;
    color: #fff;
}

.gac-board-status {
    font-weight: 700;
    margin: 8px 0 12px;
}

.gac-board-shell {
    width: min(100%, 760px);
}

.gac-board {
    --board-size: 19;
    --cell-size: calc(100% / var(--board-size));
    position: relative;
    display: grid;
    grid-template-columns: repeat(var(--board-size), 1fr);
    grid-template-rows: repeat(var(--board-size), 1fr);
    width: 100%;
    aspect-ratio: 1;
    background-color: #d9a84f;
    border: 2px solid #6d4516;
    box-shadow: inset 0 0 0 8px rgba(255, 238, 174, 0.25);
    overflow: hidden;
}

.gac-board::before {
    content: "";
    position: absolute;
    inset: calc(var(--cell-size) / 2);
    background-image:
        linear-gradient(to right, rgba(45, 27, 6, 0.78) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(45, 27, 6, 0.78) 1px, transparent 1px);
    background-size:
        calc(100% / (var(--board-size) - 1)) calc(100% / (var(--board-size) - 1)),
        calc(100% / (var(--board-size) - 1)) calc(100% / (var(--board-size) - 1));
    pointer-events: none;
}

.gac-board-point {
    position: relative;
    z-index: 1;
    display: block;
    width: 100%;
    height: 100%;
    border: 0;
    background: transparent;
    padding: 0;
    cursor: pointer;
}

.gac-board-point::after {
    content: "";
    position: absolute;
    width: 78%;
    height: 78%;
    left: 11%;
    top: 11%;
    border-radius: 50%;
}

.gac-board-point[data-stone="black"]::after {
    background: radial-gradient(circle at 34% 28%, #555, #050505 62%);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.45);
}

.gac-board-point[data-stone="white"]::after {
    background: radial-gradient(circle at 34% 28%, #fff, #d9d9d9 68%);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.3), inset 0 0 0 1px #a8a8a8;
}

.gac-board-point.is-star::before {
    content: "";
    position: absolute;
    z-index: -1;
    width: 22%;
    height: 22%;
    left: 39%;
    top: 39%;
    border-radius: 50%;
    background: #2d1b06;
}

@media (max-width: 720px) {
    .gac-board-toolbar {
        align-items: stretch;
    }

    .gac-board-group {
        width: 100%;
    }

    .gac-board-toolbar button {
        flex: 1;
        padding: 9px 8px;
    }
}