:root {
  --bg-color: #1b5e20;

  --text-color: #fff;

  --link-color: var(--text-color);
  --link-color--hover: #000;

  --calcard-color: #fff;
  --calcard-bg-color: #c62828;
  --calcard-bg-color__locked: #003300;

  --door-bg-color: #4c8c4a;
  --door-color: #fff;

  --player-controls-bg-color: #1b5e20;

  --door-hint-bg-color: #c62828;
}

html {
  font-family: "Charm", cursive;
  font-size: 100%;
}

body {
  margin: 0;
  padding: 2rem 12rem;

  color: var(--text-color);
  background-color: var(--bg-color);

  position: relative;
}

a {
  color: var(--link-color);
  cursor: pointer;

  &:hover {
    color: var(--link-color--hover);
  }
}

.hidden {
  position: absolute;
  left: -5000px;
}

.header {
  display: flex;
  width: 100%;

  h1 {
    flex-grow: 1;
    font-size: 3rem;
  }

  .yay-gif-video {
    max-height: 12rem;
    max-width: 20rem;
  }
}

.cal {
  padding-left: 0;

  display: grid;
  grid-template-columns: repeat(6, 1fr);
  grid-template-rows: repeat(4, 6vw);
  grid-gap: 2rem;

  .calcard {
    color: var(--calcard-color);
    background-color: var(--calcard-bg-color);

    cursor: pointer;

    border-radius: 6px;
    box-shadow: 2px 2px 8px 3px #000;

    display: flex;
    justify-content: center;

    &__locked {
      background-color: var(--calcard-bg-color__locked);
      cursor: not-allowed;
    }

    & .cardnumber {
      font-size: 6vw;
    }
  }
}

.door-mask {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;

  background-color: rgba(0, 0, 0, 0.4);
}

.door {
  background-color: var(--door-bg-color);
  color: var(--door-color);

  padding: 2rem;

  text-align: center;
  font-size: 1.7rem;

  border-radius: 6px;
  box-shadow: 2px 2px 8px 3px #000;

  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);

  min-width: 30rem;

  .solve {
    font-size: 2rem;
    margin-top: 24px;
  }

  .hint {
    margin-top: 12px;
    padding: 12px;

    text-align: left;

    background-color: var(--door-hint-bg-color);
    border-radius: 3px;
    box-shadow: 2px 2px 8px 3px #000;
  }

  .door-close {
    font-size: 1.5rem;
    position: absolute;

    top: 0.5rem;
    right: 1rem;
  }

  .player-controls {
    display: inline-flex;

    a {
      width: 2rem;
      margin-left: 16px;
      padding: 0 6px;
      background-color: var(--player-controls-bg-color);
      border-radius: 3px;
      box-shadow: 2px 2px 3px 2px #000;
    }
  }
}

.ad-nav {
  & nav {
    text-align: center;
  }

  & ul {
    display: flex;
  }

  & nav > ul {
    padding: 4px 16px;
  }

  & li {
    display: flex;
    padding: 6px 8px;
  }
}