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HTML 

              
                <!-- 手順7 -->
<div class="board">
    <!-- 手順3 -->
    <!-- 〇の選択 -->
    <input id="precedence-1" class="chk-board-item item-1" type="checkbox">
    <input id="precedence-2" class="chk-board-item item-2" type="checkbox">
    <input id="precedence-3" class="chk-board-item item-3" type="checkbox">
    <input id="precedence-4" class="chk-board-item item-4" type="checkbox">
    <input id="precedence-5" class="chk-board-item item-5" type="checkbox">
    <input id="precedence-6" class="chk-board-item item-6" type="checkbox">
    <input id="precedence-7" class="chk-board-item item-7" type="checkbox">
    <input id="precedence-8" class="chk-board-item item-8" type="checkbox">
    <input id="precedence-9" class="chk-board-item item-9" type="checkbox">
    
    <!-- ×の選択 -->
    <input id="second-1" class="chk-board-item item-1" type="checkbox">
    <input id="second-2" class="chk-board-item item-2" type="checkbox">
    <input id="second-3" class="chk-board-item item-3" type="checkbox">
    <input id="second-4" class="chk-board-item item-4" type="checkbox">
    <input id="second-5" class="chk-board-item item-5" type="checkbox">
    <input id="second-6" class="chk-board-item item-6" type="checkbox">
    <input id="second-7" class="chk-board-item item-7" type="checkbox">
    <input id="second-8" class="chk-board-item item-8" type="checkbox">
    <input id="second-9" class="chk-board-item item-9" type="checkbox">
    
    <!-- 手順1 -->
    <div class="board-grid board-display">
        <div id="display-1" class="board-display-item"></div>
        <div id="display-2" class="board-display-item"></div>
        <div id="display-3" class="board-display-item"></div>
        <div id="display-4" class="board-display-item"></div>
        <div id="display-5" class="board-display-item"></div>
        <div id="display-6" class="board-display-item"></div>
        <div id="display-7" class="board-display-item"></div>
        <div id="display-8" class="board-display-item"></div>
        <div id="display-9" class="board-display-item"></div>
    </div>
    
    <!-- 手順2 -->
    <div class="board-grid board-precedence">
        <label class="board-item item-1" for="precedence-1"></label>
        <div class="board-item-void item-1"></div>
        <label class="board-item item-2" for="precedence-2"></label>
        <div class="board-item-void item-2"></div>
        <label class="board-item item-3" for="precedence-3"></label>
        <div class="board-item-void item-3"></div>
        <label class="board-item item-4" for="precedence-4"></label>
        <div class="board-item-void item-4"></div>
        <label class="board-item item-5" for="precedence-5"></label>
        <div class="board-item-void item-5"></div>
        <label class="board-item item-6" for="precedence-6"></label>
        <div class="board-item-void item-6"></div>
        <label class="board-item item-7" for="precedence-7"></label>
        <div class="board-item-void item-7"></div>
        <label class="board-item item-8" for="precedence-8"></label>
        <div class="board-item-void item-8"></div>
        <label class="board-item item-9" for="precedence-9"></label>
        <div class="board-item-void item-9"></div>
    </div>
    
    <div class="board-grid board-second">
        <label class="board-item item-1" for="second-1"></label>
        <div class="board-item-void item-1"></div>
        <label class="board-item item-2" for="second-2"></label>
        <div class="board-item-void item-2"></div>
        <label class="board-item item-3" for="second-3"></label>
        <div class="board-item-void item-3"></div>
        <label class="board-item item-4" for="second-4"></label>
        <div class="board-item-void item-4"></div>
        <label class="board-item item-5" for="second-5"></label>
        <div class="board-item-void item-5"></div>
        <label class="board-item item-6" for="second-6"></label>
        <div class="board-item-void item-6"></div>
        <label class="board-item item-7" for="second-7"></label>
        <div class="board-item-void item-7"></div>
        <label class="board-item item-8" for="second-8"></label>
        <div class="board-item-void item-8"></div>
        <label class="board-item item-9" for="second-9"></label>
        <div class="board-item-void item-9"></div>
    </div>
    
    <!-- 手順6 -->
    <div class="board-result"></div>
</div>
!

CSS 

              
                /* 手順1 */
.board-grid {
    display: grid;
    grid-template-columns: 100px 100px 100px;
    grid-template-rows: 100px 100px 100px;
    column-gap: 5px;
    row-gap: 5px;
    padding: 15px;
    width: max-content;
}

.board-display {
    background: #333;
    border-radius: 15px;
}

.board-display .board-display-item {
    background-color: #55ff55;
}

/* 手順2 */
/* 〇の場合 */
.board-precedence .board-item {
    background-color: #cc5555;
}

/* ×の場合 */
.board-second .board-item {
    background-color: #5555cc;
}

/* 選択済みの表現で利用します。 */
.board-item-void {
    display: none;
}

/* 手順3 */
.chk-board-item {
    display: none;
}

.chk-board-item.item-1:checked ~ .board-grid .board-item.item-1,
.chk-board-item.item-2:checked ~ .board-grid .board-item.item-2,
.chk-board-item.item-3:checked ~ .board-grid .board-item.item-3,
.chk-board-item.item-4:checked ~ .board-grid .board-item.item-4,
.chk-board-item.item-5:checked ~ .board-grid .board-item.item-5,
.chk-board-item.item-6:checked ~ .board-grid .board-item.item-6,
.chk-board-item.item-7:checked ~ .board-grid .board-item.item-7,
.chk-board-item.item-8:checked ~ .board-grid .board-item.item-8,
.chk-board-item.item-9:checked ~ .board-grid .board-item.item-9 {
    display: none;
}

.chk-board-item.item-1:checked ~ .board-grid .board-item-void.item-1,
.chk-board-item.item-2:checked ~ .board-grid .board-item-void.item-2,
.chk-board-item.item-3:checked ~ .board-grid .board-item-void.item-3,
.chk-board-item.item-4:checked ~ .board-grid .board-item-void.item-4,
.chk-board-item.item-5:checked ~ .board-grid .board-item-void.item-5,
.chk-board-item.item-6:checked ~ .board-grid .board-item-void.item-6,
.chk-board-item.item-7:checked ~ .board-grid .board-item-void.item-7,
.chk-board-item.item-8:checked ~ .board-grid .board-item-void.item-8,
.chk-board-item.item-9:checked ~ .board-grid .board-item-void.item-9 {
    display: block;
}

/* 手順4 */
.board-display-item {
    display: flex;
    align-items: center;
    justify-content: center;
}

.board-display-item::before {
    --mark: "";
    content: var(--mark);
    font-size: 100px;
}

#precedence-1:checked ~ .board-grid #display-1::before,
#precedence-2:checked ~ .board-grid #display-2::before,
#precedence-3:checked ~ .board-grid #display-3::before,
#precedence-4:checked ~ .board-grid #display-4::before,
#precedence-5:checked ~ .board-grid #display-5::before,
#precedence-6:checked ~ .board-grid #display-6::before,
#precedence-7:checked ~ .board-grid #display-7::before,
#precedence-8:checked ~ .board-grid #display-8::before,
#precedence-9:checked ~ .board-grid #display-9::before {
    --mark: "〇";
}

#second-1:checked ~ .board-grid #display-1::before,
#second-2:checked ~ .board-grid #display-2::before,
#second-3:checked ~ .board-grid #display-3::before,
#second-4:checked ~ .board-grid #display-4::before,
#second-5:checked ~ .board-grid #display-5::before,
#second-6:checked ~ .board-grid #display-6::before,
#second-7:checked ~ .board-grid #display-7::before,
#second-8:checked ~ .board-grid #display-8::before,
#second-9:checked ~ .board-grid #display-9::before {
    --mark: "×";
}

/* 手順5 */
.board-grid.board-precedence {
    display: var(--precedence-board);
}

.board-grid.board-second {
    display: var(--second-board);
}

.board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid {
    --precedence-board: grid;
    --second-board: none;
}

.chk-board-item:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid {
    --precedence-board: none;
    --second-board: grid;
}

/* 手順6 */
.board-result::before {
    --result: "";
    content: var(--result);
}

#precedence-1:checked ~ #precedence-2:checked ~ #precedence-3:checked ~ .board-result::before,
#precedence-4:checked ~ #precedence-5:checked ~ #precedence-6:checked ~ .board-result::before,
#precedence-7:checked ~ #precedence-8:checked ~ #precedence-9:checked ~ .board-result::before,
#precedence-1:checked ~ #precedence-4:checked ~ #precedence-7:checked ~ .board-result::before,
#precedence-2:checked ~ #precedence-5:checked ~ #precedence-8:checked ~ .board-result::before,
#precedence-3:checked ~ #precedence-6:checked ~ #precedence-9:checked ~ .board-result::before,
#precedence-1:checked ~ #precedence-5:checked ~ #precedence-9:checked ~ .board-result::before,
#precedence-3:checked ~ #precedence-5:checked ~ #precedence-7:checked ~ .board-result::before {
    --result: "〇の勝利";
}

#second-1:checked ~ #second-2:checked ~ #second-3:checked ~ .board-result::before,
#second-4:checked ~ #second-5:checked ~ #second-6:checked ~ .board-result::before,
#second-7:checked ~ #second-8:checked ~ #second-9:checked ~ .board-result::before,
#second-1:checked ~ #second-4:checked ~ #second-7:checked ~ .board-result::before,
#second-2:checked ~ #second-5:checked ~ #second-8:checked ~ .board-result::before,
#second-3:checked ~ #second-6:checked ~ #second-9:checked ~ .board-result::before,
#second-1:checked ~ #second-5:checked ~ #second-9:checked ~ .board-result::before,
#second-3:checked ~ #second-5:checked ~ #second-7:checked ~ .board-result::before {
    --result: "×の勝利";
}

.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-result::before {
    --result: "引き分け";
}

/* 勝敗が追加時に選択できないようにします。 */
#precedence-1:checked ~ #precedence-2:checked ~ #precedence-3:checked ~ .board-grid,
#precedence-4:checked ~ #precedence-5:checked ~ #precedence-6:checked ~ .board-grid,
#precedence-7:checked ~ #precedence-8:checked ~ #precedence-9:checked ~ .board-grid,
#precedence-1:checked ~ #precedence-4:checked ~ #precedence-7:checked ~ .board-grid,
#precedence-2:checked ~ #precedence-5:checked ~ #precedence-8:checked ~ .board-grid,
#precedence-3:checked ~ #precedence-6:checked ~ #precedence-9:checked ~ .board-grid,
#precedence-1:checked ~ #precedence-5:checked ~ #precedence-9:checked ~ .board-grid,
#precedence-3:checked ~ #precedence-5:checked ~ #precedence-7:checked ~ .board-grid,
#second-1:checked ~ #second-2:checked ~ #second-3:checked ~ .board-grid,
#second-4:checked ~ #second-5:checked ~ #second-6:checked ~ .board-grid,
#second-7:checked ~ #second-8:checked ~ #second-9:checked ~ .board-grid,
#second-1:checked ~ #second-4:checked ~ #second-7:checked ~ .board-grid,
#second-2:checked ~ #second-5:checked ~ #second-8:checked ~ .board-grid,
#second-3:checked ~ #second-6:checked ~ #second-9:checked ~ .board-grid,
#second-1:checked ~ #second-5:checked ~ #second-9:checked ~ .board-grid,
#second-3:checked ~ #second-5:checked ~ #second-7:checked ~ .board-grid,
.chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .chk-board-item:checked ~ .board-grid {
    --precedence-board: none;
    --second-board: none;
}

/* 手順7 */
.board {
    position: relative;
}

.board-precedence,
.board-second {
    top:0;
    left: 0;
    position: absolute;
}
!

JS
!
999px

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