:root {
    --Dark-navy: hsl(202, 32%, 15%);
    --Semi-dark-navy: hsl(199, 35%, 19%);
    --Silver: hsl(198, 23%, 72%);
    --Silver-hover: hsl(197, 33%, 89%);
    --Light-yellow: hsl(39, 88%, 58%);
    --Light-blue: hsl(178, 60%, 48%);
    --Light-yellow-hover: hsl(39, 100%, 69%);
    --Light-blue-hover: hsl(178, 75%, 65%);
    --On-hover-transition: 250ms ease-in-out;
    --Cell-size: 8.75rem;
    --X-mark: url(./images/icon-x.svg);
    --X-mark-hover: url(./images/icon-x-outline.svg);
    --Circle-mark: url(./images/icon-o.svg);
    --Circle-mark-hover: url(./images/icon-o-outline.svg);
    --Box-shadow-large-button: 0 -0.5rem 0 0 hsl(201, 45%, 11%) inset;
    --Box-shadow-light: 0 -0.5rem 0 0 hsl(199, 17%, 51%) inset;
  }
  
  *,
  *::after,
  *::before {
    box-sizing: border-box;
  }
  
  body {
    display: flex;
    min-height: 100vh;
    justify-content: center;
    align-items: center;
    margin: 0;
    background: var(--Dark-navy);
    font-family: "Outfit", sans-serif;
    font-feature-settings: "clig" off, "liga" off;
  }
  
  button {
    width: 28.75rem;
    height: 4.18rem;
    border: none;
    cursor: pointer;
    transition: var(--On-hover-transition);
  }
  
  .show {
    display: block;
  }
  
  .hide {
    display: none;
  }
  
  .logo {
    display: flex;
    max-inline-size: 100%;
    justify-content: center;
  }
  
  .secondary-container {
    display: flex;
    flex-direction: column;
    width: 28.75rem;
    justify-content: center;
    align-items: center;
    margin: auto;
    background: var(--Dark-navy);
    color: white;
  }
  
  .third-container {
    display: grid;
    grid-template-columns: repeat(2, 2fr);
    height: 4.5rem;
    padding: 0 0.5rem;
    justify-content: center;
    align-items: center;
    background: var(--Dark-navy);
    border-radius: 0.6rem;
  }
  
  .player-one-container {
    background: var(--Light-blue);
  }
  
  .ties-score-container {
    background: var(--Silver);
  }
  
  .player-two-container {
    background: var(--Light-yellow);
  }
  
  .pick-player-container {
    margin: 2.5rem auto;
    padding: 0.5rem auto;
    background: var(--Semi-dark-navy);
    box-shadow: 0 -0.5rem 0 0 hsl(201, 45%, 11%) inset;
    border-radius: 1rem;
  }
  
  .pick-player-button {
    display: flex;
    width: fit-content;
    height: 3.4rem;
    padding: 0;
    border: none;
    justify-content: center;
    align-items: center;
    background: none;
  }
  
  .icon-x,
  .icon-circle {
    width: 12.4rem;
    height: 3.4rem;
    margin: 0;
    padding-bottom: 1rem;
    font-family: "Mochiy Pop One", sans-serif;
    font-size: 2.5rem;
    color: var(--Silver);
    border-radius: 0.6rem;
    transition: var(--On-hover-transition);
  }
  
  .icon-x:hover,
  .icon-circle:hover {
    background: var(--Silver-hover);
  }
  
  .icon-x:hover:not(.light-background),
  .icon-circle:hover:not(.light-background) {
    background: var(--Semi-dark-navy);
  }
  
  .light-background {
    background: var(--Silver);
    color: var(--Dark-navy);
  }
  
  .dark-background {
    background: var(--Dark-navy);
    color: var(--Silver);
  }
  
  .button-yellow {
    background: var(--Light-yellow);
    border-radius: 1rem;
    color: var(--Dark-navy);
  }
  
  .button-yellow:hover {
    background: var(--Light-yellow-hover);
  }
  
  .button-blue {
    background: var(--Light-blue);
    box-shadow: 0 -0.5rem 0 0 hsl(178, 78%, 31%) inset;
    border-radius: 1rem;
  }
  
  .button-blue:hover {
    background: var(--Light-blue-hover);
  }
  
  .button-font {
    font-size: 1.25rem;
    font-style: normal;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06rem;
    line-height: normal;
    color: var(--Dark-navy);
  }
  
  .header {
    margin: 2rem auto;
    color: var(--Silver);
    text-transform: uppercase;
  }
  
  .font-one {
    margin: 1.5rem auto;
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 0.06rem;
  }
  
  .font-two {
    margin-block-end: 1.5rem;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.06rem;
    opacity: 0.5;
  }
  
  .game-board-grid > *,
  .score-board,
  .game-board-navbar {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    margin: 1.25rem;
    gap: 1.25rem;
  }
  
  .game-board-grid span {
    display: flex;
    width: var(--Cell-size);
    height: var(--Cell-size);
    background: var(--Semi-dark-navy);
    box-shadow: 0 -0.5rem 0 0 hsl(201, 45%, 11%) inset;
    border-radius: 1rem;
    cursor: pointer;
  }
  
  .navbar-item {
    max-inline-size: 100%;
    text-align: center;
  }
  
  .navbar-logo {
    display: flex;
    align-items: center;
    text-align: start;
  }
  
  .turn-button {
    display: inline-flex;
    width: 8.75rem;
    height: 3.25rem;
    justify-content: center;
    align-items: center;
    background: var(--Semi-dark-navy);
    box-shadow: 0 -0.25rem 0 0 hsl(201, 45%, 11%) inset;
    text-align: center;
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 0.06rem;
    line-height: normal;
    text-transform: uppercase;
    color: var(--Silver);
    border-radius: 0.6rem;
  }
  
  .turnButton-color {
    width: 1.25rem;
    height: 1.25rem;
    filter: brightness(0) saturate(100%) invert(80%) sepia(17%) saturate(264%)
      hue-rotate(153deg) brightness(91%) contrast(92%);
  }
  
  .turn-icon {
    width: 1rem;
    height: 1rem;
    margin-inline-end: 0.6rem;
  }
  
  .turn-button p {
    margin: 0;
  }
  
  .restart {
    display: flex;
    justify-content: end;
  }
  
  .restart-button {
    width: 3.25rem;
    height: 3.25rem;
    background: var(--Silver);
    box-shadow: 0 -0.25rem 0 0 hsl(199, 17%, 51%) inset;
    transition: var(--On-hover-transition);
    border-radius: 0.6rem;
  }
  
  .restart-button:hover {
    background: var(--Silver-hover);
  }
  
  .restart-button i {
    font-size: 1.25rem;
  }
  
  .score-board {
    margin: 0 0 1.25rem 0;
  }
  
  .score-board-item {
    display: flex;
    width: 8.75rem;
    height: 4.5rem;
    justify-content: center;
    align-items: center;
    text-align: center;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.06rem;
    text-transform: uppercase;
    color: var(--Dark-navy);
    border-radius: 1rem;
  }
  
  .score-item {
    display: inline-flex;
    flex-direction: column;
    max-inline-size: 100%;
    height: 3.5rem;
    justify-content: center;
    align-items: center;
  }
  
  .score-item p {
    margin: 0;
  }
  
  .number-score {
    font-weight: 700;
    font-size: 1.5rem;
    letter-spacing: 0.1rem;
  }
  
  .game-end-message,
  .restart-game-message,
  .game-tied-message,
  .new-game-vs-player-alert {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    flex-direction: column;
    background-color: rgba(0, 0, 0, 0.5);
    justify-content: center;
    align-items: center;
  }
  
  .game-end-container,
  .restart-game-container,
  .game-tied-container,
  .new-game-vs-player-alert-container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 16.6rem;
    min-width: 100%;
    background: var(--Semi-dark-navy);
    text-align: center;
  }
  
  .game-end-container h2,
  .game-tied-container h2 {
    margin: 0;
    color: var(--Silver);
  }
  
  .game-end-container h3,
  .restart-game-container h3,
  .new-game-vs-player-alert h2,
  .game-tied-container h3 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: 0.2rem;
    text-transform: uppercase;
  }
  
  .restart-game-container h3,
  .new-game-vs-player-alert h2,
  .game-tied-container h2 {
    margin: 1.5rem 0 2rem 0;
    color: var(--Silver);
  }
  
  .game-end-buttons {
    display: flex;
    margin-inline-end: 1.6rem;
  }
  
  .game-end-header-large img {
    width: 4rem;
    height: 4rem;
  }
  
  .quit-button,
  .quit-tied-button {
    width: 4.75rem;
    height: 3.25rem;
    margin-inline-end: 1rem;
    background: var(--Silver);
    box-shadow: 0 -0.25rem 0 0 hsl(199, 17%, 51%) inset;
    color: var(--Dark-navy);
  }
  
  .cancel-restart-button,
  .back-button,
  .next-round-button,
  .next-round-tied-button,
  .confirm-restart-button,
  .game-end-container h2,
  .restart-game-container h2,
  .game-tied-container h2,
  .quit-button,
  .quit-tied-button {
    text-align: center;
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 0.06rem;
    text-transform: uppercase;
    border-radius: 0.6rem;
  }
  
  .cancel-restart-button,
  .back-button {
    width: 8.7rem;
    height: 3.25rem;
    margin-inline-end: 1rem;
    background: var(--Silver);
    color: var(--Dark-navy);
    box-shadow: 0 -0.25rem 0 0 hsl(199, 17%, 51%) inset;
  }
  
  .cancel-restart-button:hover,
  .back-button:hover,
  .quit-button:hover {
    background: var(--Silver-hover);
  }
  
  .next-round-button,
  .next-round-tied-button,
  .confirm-restart-button {
    width: 9rem;
    height: 3.25rem;
    background: var(--Light-yellow);
    box-shadow: 0 -0.25rem 0 0 hsl(39, 83%, 44%) inset;
  }
  
  .next-round-button:hover,
  .next-round-tied-button:hover,
  .confirm-restart-button:hover {
    background: var(--Light-yellow-hover);
  }
  
  #x-aiPlayer,
  #x-humanPlayer {
    background-position: center;
    background-repeat: no-repeat;
    background-image: var(--X-mark);
    pointer-events: none;
  }
  
  #circle-aiPlayer,
  #circle-humanPlayer {
    background-position: center;
    background-repeat: no-repeat;
    background-image: var(--Circle-mark);
    pointer-events: none;
  }
  
  #new-game-solo {
    margin-bottom: 1.25rem;
    box-shadow: 0 -0.5rem 0 0 hsl(39, 83%, 44%) inset;
  }
  
  #game-end-message.show,
  #restart-game-message.show,
  #game-tied-message.show,
  #new-game-vs-player-alert.show {
    display: flex;
  }
  
  #game-tied-message h1 {
    margin-block-start: 0;
  }
  
  #main-content,
  #game-board {
    justify-content: center;
    align-content: center;
  }
  
  @media only screen and (max-width: 576px) {
    .secondary-container {
      width: fit-content;
    }
  
    .pick-player-container {
      position: relative;
      width: 20.4rem;
      height: fit-content;
    }
  
    .pick-players {
      width: 19rem;
      height: 4.5rem;
    }
  
    .pick-player-button {
      width: 100%;
    }
  
    .button-yellow,
    .button-blue {
      width: 20.4rem;
      height: 3.5rem;
    }
  
    .game-board-grid {
      margin-block-start: 4.4rem;
    }
  
    .game-board-navbar {
      border: 1px solid white;
    }
  
    .turn-button {
      width: 6rem;
      height: 2.5rem;
      font-weight: normal;
      font-size: 0.9rem;
    }
  
    .game-board-grid span {
      width: 6rem;
      height: 6rem;
    }
  
    .score-board-item {
      width: 6rem;
      height: 4rem;
    }
  
    .game-end-container h2 {
      margin: 1.6rem 1.6rem;
      font-size: 1.7rem;
    }
  
    .game-end-buttons {
      margin-block-start: 0.6rem;
    }
  
    .restart-button {
      width: 2.5rem;
      height: 2.5rem;
    }
  
    .restart-button i {
      font-size: 1rem;
    }
  
    .turnButton-color {
      width: 1rem;
      height: 1rem;
    }
  
    .game-end-header-large img {
      width: 2rem;
      height: 2rem;
    }
  
    #x-aiPlayer,
    #x-humanPlayer,
    #circle-aiPlayer,
    #circle-humanPlayer {
      background-size: 2.5rem 2.5rem;
    }
  }