@import url('https://fonts.googleapis.com/css2?family=Quicksand:wght@300;400;500;700&display=swap');

*, *::after, *::before {
    box-sizing: border-box;
    user-select: none;
    font-family: 'Quicksand', sans-serif;
    margin: 0;
    padding: 0;
}

:root {
    --cell-size: 100px;
    --mark-size: calc(var(--cell-size) * .9);
}


body {
    margin: 0;
    overflow: hidden;
}

.header {
    background-color: #171717;
    color: #fff;
    padding: 15px;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    text-align: center;
    height: fit-content;
}

.whoDeveloped {
    background-color: #171717;
    padding: 20px;
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    text-align: center;
    height: fit-content;
}

.whoDeveloped a{
    text-decoration: none;
    color: #fff;
}

.whoDeveloped h1 {
    animation: whoDevelopedAnimation 1s ease infinite;
}

.header h1 {
    font-weight: 700 !important;
    font-size: 40px;
}

.board {
    width: 100vw;
    height: 90vh;
    display: grid;
    justify-content: center;
    justify-items: center;
    align-items: center;
    align-content: center;
    grid-template-columns: repeat(3, auto);
}

.cell {
    width: var(--cell-size);
    height: var(--cell-size);
    border: 1px solid #000;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    cursor: pointer;
}

.cell:first-child,
.cell:nth-child(2),
.cell:nth-child(3) {
    border-top: none;
}

.cell:nth-child(3n + 1) {
    border-left: none;
}

.cell:nth-child(3n + 3) {
    border-right: none;
}

.cell:last-child,
.cell:nth-child(7),
.cell:nth-child(8) {
    border-bottom: none;
}

.cell.x, .cell.circle {
    cursor: not-allowed;
}

.cell.x::before,
.cell.x::after {
    background-color: black;
}

.cell.circle::before,
.cell.circle::after {
    background-color: #000;

}

.board.x .cell:not(.x):not(.circle):hover::before,
.board.x .cell:not(.x):not(.circle):hover::after,
.board.circle .cell:not(.x):not(.circle):hover::before,
.board.circle .cell:not(.x):not(.circle):hover::after {
    background-color: lightgray;
}



.cell.x::before,
.cell.x::after,
.board.x .cell:not(.x):not(.circle):hover::before,
.board.x .cell:not(.x):not(.circle):hover::after {
    content: '';
    position: absolute;
    width: calc(var(--mark-size) * .15);
    height: var(--mark-size);
}

.cell.x::before, .board.x .cell:not(.x):not(.circle):hover::before {
    transform: rotate(45deg);
}

.cell.x::after, .board.x .cell:not(.x):not(.circle):hover::after {
    transform: rotate(-45deg);
}

.cell.circle::before,
.cell.circle::after,
.board.circle .cell:not(.x):not(.circle):hover::after,
.board.circle .cell:not(.x):not(.circle):hover::before {
    content: '';
    position: absolute;
    border-radius: 50%;
}


.cell.circle::before,
.board.circle .cell:not(.x):not(.circle):hover::before {
    width: var(--mark-size);
    height: var(--mark-size);
}

.cell.circle::after,
.board.circle .cell:not(.x):not(.circle):hover::after {
    width: calc(var(--mark-size) * .7);
    height: calc(var(--mark-size) * .7);
    background-color: #fff;
}

.winning-message {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, .9);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #fff;
    font-size: 5rem;
    z-index: 1;
}

.winning-message button {
    font-size: 3rem;
    background-color: #fff;
    border: 1px solid black;
    padding: .25em 5em;
    cursor: pointer;
    transition: all .5s linear;
    border-radius: 20px;
}

.winning-message button:hover {
    background-color: #ff0000;
    color: #fff;
}

.winning-message.show {
    display: flex;
}


@keyframes whoDevelopedAnimation {

    0% {
        text-shadow: 0px 0px 20px #ccc;
    }

    50% {
        text-shadow: 0px 0px 0px #ccc;
    }

    100% {
        text-shadow: 0px 0px 20px #ccc;
    }
}