p{
    margin:0;
}

body{
    background-color: #f9f2e7;
}

div{
    display: block;
}

/*标题*/
h1{
    text-align: center;
    font-size: 60px;
    color: #477998;
}

/*游戏内容容器*/
.container{
    /* position: relative; */
    width: 471px;
    height: 471px;
    margin: 0 auto;
}

#bord{
    height: 471px;
    width: 471px;
}
.row{
    display: flex;/*弹性布局 ，子元素的float clear vertical-align 将失效*/
}
.cell.last-row{
    border-bottom: 0;
} 
.cell:last-child {
    border-right: 0;
}

.cell{
    flex: 1;
    width: 157px;
    height: 157px;
    line-height: 157px;
    box-sizing: border-box;
    border-right: 6px solid #546363;
    border-bottom: 6px solid #546363;
    text-align: center;
    cursor : pointer;
}
.no-hover {
    pointer-events: none;
}

.cell:hover::before {
    content: attr(hover);
    font-size: 100px;
    color: #747474fa;
    display: block;
    opacity: 0.2;/*透明度 */
}

.x::before{
    content: "x";
    font-size:100px;
    color: rgb(21, 151, 238);
    display: block;

}
.o::before{
    content: "o";
    font-size:100px;
    color: rgb(21, 238, 57);
    display: block;

}
.game-message {
    display: none;
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(69, 133, 136, 0.4);
    text-align: center;
}
#winner {
    /* font-family: sans-serif; */
    color: yellow;
    text-shadow: 0 0 6px #ff0000;
    font-size: 40px;
    margin-top: 100px;
}
#restart {
    font-size: 30px;
    padding: 10px;
    border-radius: 15px;
    border-color: #f9f2e7;
    box-shadow: 0px 2px 6px 2px rgba(0, 0, 0, 0.75);
    color: #5682a1;
    margin-top: 120px;
}