*, *::before, *::after {    
    box-sizing: border-box;
    font-family: Arial;
    font-weight: bold;
}

body {
    background-color: #333;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    font-size: 7.5vmin;
}

#messages {
    position: fixed;
    z-index: 999;
    color: #f00;
    text-align: center;
    margin: 0;
}

.score {
    display: flex;
    gap: 10px;
}

.score p {
    color: #fff;
    text-transform: uppercase;
    margin: 0;
    font-size: 0.5em;
}

#messages h3 {
    scale: 0;
    display: none;
    font-size: 2.5em;
    margin: 0;
    padding: 0.05em;
    background: rgba(0,0,0,.5);
}

#messages.win h3.win {
    scale: 1;
    display: block;    
}

#messages.lose h3.lose {
    scale: 1;
    display: block;
}

#messages .messages-reset-button {
    display: none;
    scale: 0;
    margin: 0;  
}

#messages.win .messages-reset-button, #messages.lose .messages-reset-button {
    display: block;
    scale: 1;
}

#settings-container {
    display: flex;
    justify-content: center;
    align-items: flex-start;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    opacity: 0;
    pointer-events: none;
    transition: 0.4s;
    background-color: rgba(0, 0, 0, 0.2);
    z-index: 999;
}

#settings {
    align-items: center;
    flex-direction: column;
    border: 0.15em solid #000;
    padding: 0.5em;
    display: flex;
    background-color: #474747;
}

#settings-container:target {
    opacity: 1;
    pointer-events: all;
}

#settings #target {
    margin: 0.25em;
    font-size: 1em;
    width: 3.45em;
    border: 0.15em solid #000;
    border-radius: 0;
}

#settings #target:focus {
    border-radius: 0;
}

#settings .message {
    color: #f00;
}

.close-button {
    padding: 0.2em;
    border: 0.2em solid;
    color: #fff;
    text-decoration: none;
    text-transform: uppercase;
}

.close-button:hover {
    color: #000;
    background-color: #fff;
    border-color: #fff;
    cursor: pointer;
}

#settings .grid-size {
    display: flex;
    flex-direction: column;
    align-items: center;
}

#settings .grid-size label, #settings .grid-size select {
    float: left;
    clear: both;
}

#settings .grid-size label {
    font-size: 0.7em;
    color: #fff;
}

#settings .grid-size select {
    font-size: 1.5em;
    border: 0.15em solid #000;
}

.settings-trigger {
    position: fixed;
    z-index: 999;
    top: 5px;
    left: 5px;
}

.settings-trigger .gaer-white {
    display: none;
}

.settings-trigger .gear-black {
    display: block;
    animation: rotateBlackCog 200ms ease-in-out;
}

.settings-trigger:hover {
    cursor: pointer;
}

.settings-trigger:hover .gaer-white {
    display: block;
    animation: rotateWhiteCog 200ms ease-in-out;
}
.settings-trigger:hover .gear-black {
    display: none;    
}

.reset-button {
    margin: 0.5em 0;
    padding: 0.2em;
    border: 0.2em solid;
    color: #fff;
    text-decoration: none;
    text-transform: uppercase;
}

.messages-reset-button {
    margin: 0.5em 0;
    padding: 0.2em;
    border: 0.2em solid;
    color: #000;
    background-color: rgba(255,255,255, 0.6);
    border-color: #fff;
    text-decoration: none;
    text-transform: uppercase;
}

.reset-button:hover {
    color: #000;
    background-color: #fff;
    border-color: #fff;
    cursor: pointer;
}

.messages-reset-button:hover {
    color: #fff;
    background-color: #000;
    border-color: #000;
    cursor: pointer;
}

#game-board {
    display: grid;
    grid-template-columns: repeat(var(--grid-size), var(--cell-size));
    grid-template-rows: repeat(var(--grid-size), var(--cell-size));
    background-color: #000;
    gap: var(--cell-gap);
    border-radius: 0;
    padding: var(--cell-gap);
    position: relative;
}

.cell {
    background-color: #aaa;
    border-radius: 0;    
}

.tile {
    font-size: var(--tile-font-size);
    position: absolute;
    display: flex;
    justify-content: center;
    align-items: center;
    width: var(--cell-size);
    height: var(--cell-size);
    border-radius: 0;
    top: calc(var(--y) * (var(--cell-size) + var(--cell-gap)) + var(--cell-gap));
    left: calc(var(--x) * (var(--cell-size) + var(--cell-gap)) + var(--cell-gap));
    background-color: hsl(200, 50%, var(--background-lightness));
    color: hsl(200, 50%, var(--text-lightness));
    animation: show 200ms ease-in-out;
    transition: 100ms ease-in-out;
}

@keyframes show {
    0% {
        opacity: 0.5;
        transform: scale(0);
    }    
}

@keyframes rotateWhiteCog {
    0% {
        transform: rotate(-90deg);
    }
}
@keyframes rotateBlackCog {
    0% {
        transform: rotate(90deg);
    }
}