@font-face {
  font-family: "Mansalva";
  src: url("fonts/Mansalva-Regular.ttf") format("truetype");
}

@font-face {
  font-family: "Lato";
  src: url("fonts/Lato-Regular.ttf") format("truetype");
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #212121;
  --clr: #2aca72;
  --clrx: #e22a2a;
  --clro: #f8c617;
}

body {
  font-family: "Lato", sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background-color: var(--bg);
}

.container {
  text-align: center;
}

h1 {
  font-family: "Mansalva", cursive;
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--clr);
}

#board {
  display: grid;
  grid-template-columns: repeat(3, 7rem);
  grid-template-rows: repeat(3, 7rem);
  gap: 0.5rem;
}

.cell {
  width: 7rem;
  height: 7rem;
  background: linear-gradient(to bottom, #171717, #242424);
  border: 1px solid #292929;
  border-radius: 10px;
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 1), 0 10px 20px rgba(0, 0, 0, 0.4);
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 2rem;
  transition: all 0.2s ease;
}

.cell:active {
  transform: translateY(5px);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 1), 0 5px 10px rgba(0, 0, 0, 0.4);
}

#winnerMessage {
  color: var(--clr);
  font-family: "Mansalva", cursive;
  font-size: 1.5rem;
  margin-top: 1rem;
}

button {
  --border-radius: 15px;
  --border-width: 4px;
  appearance: none;
  position: relative;
  margin-top: 1rem;
  padding: 1rem 2rem;
  border: 0;
  background-color: var(--bg);
  font-family: "Roboto", Arial, "Segoe UI", sans-serif;
  font-size: 1rem;
  font-weight: 600;
  color: var(--clr);
  z-index: 2;
}

button::after {
  --m-i: linear-gradient(#000, #000);
  --m-o: content-box, padding-box;
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  padding: var(--border-width);
  border-radius: var(--border-radius);
  background-image: conic-gradient(
    #488cfb,
    #29dbbc,
    #ddf505,
    #ff9f0e,
    #e440bb,
    #655adc,
    #488cfb
  );
  -webkit-mask-image: var(--m-i), var(--m-i);
  mask-image: var(--m-i), var(--m-i);
  -webkit-mask-origin: var(--m-o);
  mask-origin: var(--m-o);
  -webkit-mask-clip: var(--m-o);
  mask-clip: var(--m-o);
  -webkit-mask-composite: destination-out;
  mask-composite: exclude;
  filter: hue-rotate(0);
  animation: rotate-hue linear 500ms infinite;
  animation-play-state: paused;
}

button:hover::after {
  animation-play-state: running;
}

@keyframes rotate-hue {
  to {
    filter: hue-rotate(1turn);
  }
}

button,
button::after {
  box-sizing: border-box;
}

button:active {
  --border-width: 5px;
}

.cell.x {
  color: var(--clrx);
  font-size: 3rem;
  font-weight: bold;
}

.cell.o {
  color: var(--clro);
  font-size: 3rem;
  font-weight: bold;
}

.line {
  position: absolute;
  height: 4px;
  background-color: var(--clr);
  z-index: 1;
  display: none; /* Initially hidden */
}

.line.active {
  display: block;
}

@media (max-width: 768px) {
  #board {
    grid-template-columns: repeat(3, 5rem);
    grid-template-rows: repeat(3, 5rem);
  }

  .cell {
    width: 5rem;
    height: 5rem;
    font-size: 1.5rem;
  }

  .cell.x,
  .cell.o {
    font-size: 2rem;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.5rem;
  }

  #board {
    grid-template-columns: repeat(3, 3.5rem);
    grid-template-rows: repeat(3, 3.5rem);
  }

  .cell {
    width: 3.5rem;
    height: 3.5rem;
    font-size: 1rem;
  }

  #winnerMessage {
    font-size: 1.2rem;
  }

  button {
    position: relative;
    padding: 0.8rem 1.6rem;
    font-size: 0.8rem;
  }

  .cell.x,
  .cell.o {
    font-size: 1.6rem;
  }
}