.shudan-goban {
        --shudan-board-border-width: .25em;
        --shudan-board-border-color: #CA933A;

        --shudan-board-background-color: #EBB55B;
        --shudan-board-foreground-color: #5E2E0C;

        --shudan-black-background-color: #222;
        --shudan-black-foreground-color: #eee;

        --shudan-white-background-color: #eee;
        --shudan-white-foreground-color: #222;

        display: inline-grid;
        position: relative;
        border: var(--shudan-board-border-width) solid var(--shudan-board-border-color);
        background: url('./board.png') var(--shudan-board-background-color);
        color: var(--shudan-board-foreground-color);
    }
    .shudan-goban:not(.shudan-coordinates) {
        padding: .25em;
}

.shudan-coordx span, .shudan-coordy span {
    font-size: .6em;
}

.shudan-vertex div {
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
}

/* Busy screen */

.shudan-goban.shudan-busy::after {
    content: '';
    position: absolute;
    top: calc(-1 * var(--shudan-board-border-width));
    left: calc(-1 * var(--shudan-board-border-width));
    bottom: calc(-1 * var(--shudan-board-border-width));
    right: calc(-1 * var(--shudan-board-border-width));
    background-color: rgba(23, 10, 2, .1);
    background-image: linear-gradient(to right, transparent 30%, rgba(255, 255, 255, .2) 50%, transparent 70%);
    background-size: 19em 100%;
    background-repeat: no-repeat;
    animation: 2s linear -.5s shudan-busy infinite;
}

@keyframes shudan-busy {
    from {
        background-position: -19em 0;
    }
    to {
        background-position: calc(100% + 19em) 0;
    }
}

/* Grid lines and hoshis */

.shudan-vertex .shudan-board::before {
        content: '';
        display: block;
        position: absolute;
        top: 50%;
        left: 0;
        width: 100%;
        height: 1px;
        background: var(--shudan-board-foreground-color);
    }
    .shudan-vertex.shudan-left:not(.shudan-right) .shudan-board::before {
        left: 50%;
    }
    .shudan-vertex.shudan-right:not(.shudan-left) .shudan-board::before {
        width: 50%;
    }
    .shudan-vertex .shudan-board::after {
        content: '';
        display: block;
        position: absolute;
        top: 0;
        left: 50%;
        width: 1px;
        height: 100%;
        background: var(--shudan-board-foreground-color);
    }
    .shudan-vertex.shudan-top:not(.shudan-bottom) .shudan-board::after {
        top: 50%;
    }
    .shudan-vertex.shudan-bottom:not(.shudan-top) .shudan-board::after {
        height: calc(50% + 1px);
    }
    .shudan-vertex .shudan-hoshi {
        left: 50%;
        top: 50%;
        width: .2em;
        height: .2em;
        border-radius: 50%;
        background: var(--shudan-board-foreground-color);
        transform: translate(calc(-50% + .5px), calc(-50% + .5px));
}

/* Stone render */

.shudan-vertex .shudan-stone {
        top: .04em;
        left: .04em;
        right: .04em;
        bottom: .04em;
        width: auto;
        height: auto;
    }
    .shudan-vertex .shudan-shadow {
        border-radius: 50%;
    }
    .shudan-vertex .shudan-inner {
        text-indent: -9999rem;
        background-size: 100%;
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-dimmed .shudan-stone {
        opacity: .6;
    }
    .shudan-vertex:not(.shudan-sign_0) .shudan-shadow {
        background: rgba(23, 10, 2, .4);
        box-shadow: 0 .1em .2em rgba(23, 10, 2, .4);
    }
    .shudan-vertex.shudan-sign_1 .shudan-inner {
        background-image: url('./stone_1.png');
    }
    .shudan-vertex.shudan-sign_-1 .shudan-inner {
        background-image: url('./stone_-1.png');
}

/* Fuzzy stone placement */

.shudan-vertex:not(.shudan-sign_0).shudan-animate .shudan-stone {
        transition: transform .2s;
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_1 .shudan-stone {
        transform: translate(-.07em, 0);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_2 .shudan-stone {
        transform: translate(0, -.07em);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_3 .shudan-stone {
        transform: translate(.07em, 0);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_4 .shudan-stone {
        transform: translate(0, .07em);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_5 .shudan-stone {
        transform: translate(-.04em, -.04em);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_6 .shudan-stone {
        transform: translate(.04em, -.04em);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_7 .shudan-stone {
        transform: translate(.04em, .04em);
    }
    .shudan-vertex:not(.shudan-sign_0).shudan-shift_8 .shudan-stone {
        transform: translate(-.04em, .04em);
}

/* Markers */

.shudan-vertex .shudan-marker {
        left: 0;
        top: 0;
        text-align: center;
    }
    .shudan-vertex .shudan-marker::before,
    .shudan-vertex .shudan-marker::after {
        box-sizing: border-box;
        content: '';
        display: none;
        position: absolute;
        left: 50%;
        top: 50%;
        border: .07em solid var(--shudan-board-foreground-color);
        background: var(--shudan-board-background-color);
        transform: translate(-50%, -50%);
    }
    .shudan-vertex.shudan-sign_1 .shudan-marker::before,
    .shudan-vertex.shudan-sign_1 .shudan-marker::after {
        background: transparent;
        border-color: var(--shudan-black-foreground-color);
        color: var(--shudan-black-foreground-color);
    }
    .shudan-vertex.shudan-sign_-1 .shudan-marker::before,
    .shudan-vertex.shudan-sign_-1 .shudan-marker::after {
        background: transparent;
        border-color: var(--shudan-white-foreground-color);
        color: var(--shudan-white-foreground-color);
}

.shudan-vertex.shudan-marker_point .shudan-marker {
        left: 50%;
        top: 50%;
        width: .3em;
        height: .3em;
        border-radius: 50%;
        background: var(--shudan-board-foreground-color);
        transform: translate(-50%, -50%);
    }
    .shudan-vertex.shudan-marker_point.shudan-sign_1 .shudan-marker {
        background: var(--shudan-black-foreground-color);
    }
    .shudan-vertex.shudan-marker_point.shudan-sign_-1 .shudan-marker {
        background: var(--shudan-white-foreground-color);
}

.shudan-vertex.shudan-marker_square .shudan-marker::before,
.shudan-vertex.shudan-marker_circle .shudan-marker::before,
.shudan-vertex.shudan-marker_loader .shudan-marker::before {
        display: block;
        width: .5em;
        height: .5em;
    }
    .shudan-vertex.shudan-marker_circle .shudan-marker::before,
    .shudan-vertex.shudan-marker_loader .shudan-marker::before {
        border-radius: 50%;
    }
    .shudan-vertex.shudan-marker_loader .shudan-marker::before {
        border-left-color: transparent;
        border-top-color: transparent;
        animation: 1.5s linear 0s shudan-rotation infinite;
}

@keyframes shudan-rotation {
    from {
        transform: translate(-50%, -50%) rotate(0deg);
    }
    to {
        transform: translate(-50%, -50%) rotate(360deg);
    }
}

.shudan-vertex.shudan-marker_cross .shudan-marker {
        width: .7em;
        height: .7em;
        left: 50%;
        top: 50%;
        background: var(--shudan-board-background-color);
        transform: translate(-50%, -50%);
    }
    .shudan-vertex.shudan-marker_cross.shudan-sign_1 .shudan-marker,
    .shudan-vertex.shudan-marker_cross.shudan-sign_-1 .shudan-marker {
        background: transparent;
    }
    .shudan-vertex.shudan-marker_cross .shudan-marker::before,
    .shudan-vertex.shudan-marker_cross .shudan-marker::after {
        display: block;
        border-width: .07em 0 0 0;
        width: .7em;
        height: 0;
        margin-left: -.35em;
        margin-top: -.035em;
        transform: rotate(45deg);
    }
    .shudan-vertex.shudan-marker_cross .shudan-marker::after {
        transform: rotate(-45deg);
}

.shudan-vertex.shudan-marker_triangle .shudan-marker::before {
        display: block;
        border-top: none;
        border-left: .3em solid transparent;
        border-right: .3em solid transparent;
        border-bottom: .5em solid;
        background: none;
    }
    .shudan-vertex.shudan-marker_triangle .shudan-marker::after {
        display: block;
        border-top: none;
        border-left: .18em solid transparent;
        border-right: .18em solid transparent;
        border-bottom: .3em solid var(--shudan-board-background-color);
        transform: translate(-.18em, -.12em);
        background: none;
    }
    .shudan-vertex.shudan-marker_triangle.shudan-sign_1 .shudan-marker::after {
        border-bottom-color: var(--shudan-black-background-color);
    }
    .shudan-vertex.shudan-marker_triangle.shudan-sign_-1 .shudan-marker::after {
        border-bottom-color: var(--shudan-white-background-color);
}

.shudan-vertex.shudan-marker_label .shudan-marker::before {
        content: attr(title);
        display: inline-block;
        border: none;
        max-height: 1.67em;
        max-width: 1.67em;
        overflow: hidden;
        font-size: .6em;
        line-height: 1.1;
        text-align: center;
        text-overflow: ellipsis;
        white-space: pre;
    }
    .shudan-vertex.shudan-smalllabel .shudan-marker::before {
        max-height: 2.2em;
        max-width: 2.2em;
        font-size: .36em;
}

/* Ghost stones */

.shudan-vertex .shudan-ghost {
        left: 50%;
        top: 50%;
        width: .4em;
        height: .4em;
        opacity: .5;
        transform: translate(calc(-50% + .5px), calc(-50% + .5px));
    }
    .shudan-vertex .shudan-ghost::before {
        content: '';
        box-sizing: border-box;
        display: none;
        position: absolute;
        left: 50%;
        top: 50%;
        width: .4em;
        height: .4em;
        border-radius: 50%;
        transform: translate(-50%, -50%);
    }
    .shudan-vertex.shudan-ghost_faint .shudan-ghost {
        opacity: .3;
    }
    .shudan-vertex.shudan-sign_0.shudan-ghost_1 .shudan-ghost::before,
    .shudan-vertex.shudan-sign_0.shudan-ghost_-1 .shudan-ghost::before {
        display: block;
    }
    .shudan-vertex.shudan-ghost_1 .shudan-ghost::before {
        background: black;
    }
    .shudan-vertex.shudan-ghost_-1 .shudan-ghost::before {
        background: white;
    }
    .shudan-vertex.shudan-ghost_good .shudan-ghost::before {
        background: #59A80F;
    }
    .shudan-vertex.shudan-ghost_interesting .shudan-ghost::before {
        background: #4886D5;
    }
    .shudan-vertex.shudan-ghost_doubtful .shudan-ghost::before {
        background: #92278F;
    }
    .shudan-vertex.shudan-ghost_bad .shudan-ghost::before {
        background: #F02311;
}

/* Paint map */

.shudan-vertex.shudan-paint_1 .shudan-paint,
.shudan-vertex.shudan-paint_-1 .shudan-paint {
        opacity: .3;
    }
    .shudan-vertex.shudan-paint_1 .shudan-paint {
        background: var(--shudan-black-background-color);
    }
    .shudan-vertex.shudan-paint_-1 .shudan-paint {
        background: var(--shudan-white-background-color);
}

/* Heat map */

.shudan-vertex .shudan-heat {
        top: 50%;
        left: 50%;
        margin-left: -1px;
        margin-top: -1px;
        border-radius: 50%;
        width: 1px;
        height: 1px;
        opacity: 0;
        pointer-events: none;
        transition: opacity .5s, box-shadow .5s;
    }
    .shudan-vertex.shudan-heat_9 .shudan-heat {
        background: #59A80F;
        box-shadow: 0 0 1em 1em #59A80F;
        opacity: .8;
    }
    .shudan-vertex.shudan-heat_8 .shudan-heat {
        background: #59A80F;
        box-shadow: 0 0 1em .9em #59A80F;
        opacity: .7;
    }
    .shudan-vertex.shudan-heat_7 .shudan-heat {
        background: #4886D5;
        box-shadow: 0 0 1em .75em #4886D5;
        opacity: .8;
    }
    .shudan-vertex.shudan-heat_6 .shudan-heat {
        background: #4886D5;
        box-shadow: 0 0 1em .6em #4886D5;
        opacity: .8;
    }
    .shudan-vertex.shudan-heat_5 .shudan-heat {
        background: #4886D5;
        box-shadow: 0 0 .9em .55em #4886D5;
        opacity: .7;
    }
    .shudan-vertex.shudan-heat_4 .shudan-heat {
        background: #92278F;
        box-shadow: 0 0 .85em .5em #92278F;
        opacity: .8;
    }
    .shudan-vertex.shudan-heat_3 .shudan-heat {
        background: #92278F;
        box-shadow: 0 0 .8em .45em #92278F;
        opacity: .7;
    }
    .shudan-vertex.shudan-heat_2 .shudan-heat {
        background: #F02311;
        box-shadow: 0 0 .75em .4em #F02311;
        opacity: .8;
    }
    .shudan-vertex.shudan-heat_1 .shudan-heat {
        background: #F02311;
        box-shadow: 0 0 .75em .4em #F02311;
        opacity: .7;
}

.shudan-vertex .shudan-heatlabel {
    display: inline-block;
    height: auto;
    top: 50%;
    left: 50%;
    overflow: hidden;
    color: white;
    font-size: .36em;
    line-height: 1.1;
    text-align: center;
    text-overflow: ellipsis;
    text-shadow: 0 .1em .3em black;
    white-space: pre;
    opacity: .9;
    transform: translate(-50%, -50%);
    pointer-events: none;
}

/* Selection */

.shudan-vertex .shudan-selection {
    left: -.1em;
    right: -.1em;
    top: -.1em;
    bottom: -.1em;
    border: .1em solid #0082F0;
    border-radius: 5px;
    background: rgba(0, 130, 240, .2);
}

/* Lines & arrows */

.shudan-line,
.shudan-arrow {
    height: .11em;
    background: var(--shudan-board-foreground-color);
}

.shudan-arrow::before,
.shudan-arrow::after {
        content: '';
        position: absolute;
        height: .11em;
        width: .5em;
        left: auto;
        right: 0;
        top: -.12em;
        background: var(--shudan-board-foreground-color);
        transform: rotate(30deg);
        pointer-events: none;
    }
    .shudan-arrow::after {
        top: auto;
        bottom: -.12em;
        transform: rotate(-30deg);
}