@import url('https://fonts.googleapis.com/css2?family=Inter:wght@100..900&display=swap');

:root {
  --primary-dark-color: #311e10;
  --secondary-dark-color: #9b5825;
  --primary-light-color: #ceab7e;
  --secondary-light-color: #ffffff;
  --font-weight: 400;
  --header-height: 3rem;
  --board-border: 1.5rem solid var(--primary-dark-color);
  --board-display: none;
  --border-radius: 1rem;
  --cell-size: 12.5%;
  --cell-display: none;
  --row-text: 'A B C D E F G H';
  --column-text: '8 7 6 5 4 3 2 1';
  --animation-duration: 500ms;
  --animation-timing-curve: infinite;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Inter', sans-serif;
  font-optical-sizing: auto;
  font-weight: var(--font-weight);
  font-style: normal;
  font-variation-settings: 'slnt' 0;
}

h1,
h2,
h3,
h4,
h5,
h6,
b {
  font-weight: 800;
  margin-bottom: 1rem;
}

p {
  text-align: justify;
}

ul {
  margin-left: 2rem;
}

table td {
  padding: 0.5rem;
  text-align: justify;
  vertical-align: top;
}

fieldset {
  width: 100%;
  padding: 0.5rem;
  border-radius: var(--border-radius);
}

button {
  width: 100%;
  height: 2.5rem;
  margin: 0.5rem 0;
  padding: 0.5rem;
  font-size: var(--font-size);
  color: var(--secondary-light-color);
  background-color: var(--secondary-dark-color);
  border-radius: var(--border-radius);
  border: none;
}

button:hover {
  background-color: var(--primary-light-color);
  cursor: pointer;
}

.container {
  width: min(90%, 50rem);
  display: flex;
  margin-inline: auto;
  flex-direction: column;
}

header {
  text-align: center;
  height: var(--header-height);
  margin: 1rem;
}

main {
  display: flex;
  flex-direction: row;
  gap: 2rem;
}

section {
  width: 70%;
  display: flex;
  justify-content: center;
  align-items: center;
}

aside {
  width: 30%;
  display: flex;
  align-items: center;
  flex-direction: column;
}

#board {
  width: 100%;
  aspect-ratio: 1/1;
  border: var(--board-border);
  display: flex;
  position: relative;
  cursor: pointer;
  flex-wrap: wrap;
}

#board::before {
  display: var(--board-display);
  position: absolute;
  color: var(--secondary-light-color);
  content: var(--column-text);
  top: 1.5rem;
  left: -1.2rem;
  text-align: center;
  font-size: small;
  writing-mode: vertical-rl;
  text-orientation: upright;
  letter-spacing: 0.9rem;
}

#board::after {
  display: var(--board-display);
  position: absolute;
  color: var(--secondary-light-color);
  content: var(--row-text);
  bottom: -1.2rem;
  left: 1.8rem;
  font-size: small;
  letter-spacing: 1.5rem;
}

.light {
  background-color: var(--primary-light-color);
}

.dark {
  background-color: var(--secondary-dark-color);
}

.cell {
  width: var(--cell-size);
  aspect-ratio: 1/1;
  /* text-align: center;
  line-height: center; */
  position: relative;
  background-repeat: no-repeat;
  background-size: cover;
}

.cell::before {
  display: var(--cell-display);
  position: absolute;
  right: 3px;
  top: 0;
  content: attr(cell-text);
  color: var(--primary-dark-color);
  opacity: 0.9;
  font-size: smaller;
}

.cell-selected {
  outline: 3px dashed var(--primary-dark-color);
  outline-offset: -5px;
  cursor: pointer;
  animation: selection-move var(--animation-duration)
    var(--animation-timing-curve);
}

@keyframes selection-move {
  50% {
    outline-offset: -7px;
  }
}

@media (max-width: 768px) {
  main {
    flex-direction: column;
  }

  section,
  aside {
    width: 100%;
  }

  .board::before,
  .board::after {
    display: none;
  }
}