/*=== Reset ===*/
*,
*::after,
*::before {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

img,
picture,
video {
  display: block;
  max-width: 100%;
  height: auto;
}

input,
button,
textarea,
select {
  font: inherit;
  color: inherit;
  background: none;
  border-color: transparent;
}

a {
  text-decoration: none;
  color: inherit;
}

ul,
ol {
  list-style-type: none;
}

/*=== CSS Custom Variables ===*/
:root {
  --body-background: rgb(229, 231, 235);
  --white-primary: rgba(255, 255, 255, 0.95);
  --grey-secondary: rgba(255, 255, 255, 0.65);
  --grey-tertiary: rgba(255, 255, 255, 0.45);
  --grey-disabled: rgba(255, 255, 255, 0.25);
  --playlist-active-bg: rgba(255, 255, 255, 0.12);
  --dark-box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2),
    0 6px 20px 0 rgba(0, 0, 0, 0.19);
  --slider-active-background: rgba(254, 180, 123, 0.8);

  /*== Gradient Colors ==*/
  --player-background: linear-gradient(
    180deg,
    rgb(74, 88, 117) 0%,
    rgb(95, 111, 143) 50%,
    rgb(120, 138, 170) 100%
  );
  --playlist-background: linear-gradient(
    180deg,
    rgb(120, 138, 170) 0%,
    rgb(95, 111, 143) 50%,
    rgb(74, 88, 117) 100%
  );
  --button-background: radial-gradient(
    circle at top,
    rgb(139, 157, 187),
    rgb(120, 138, 170)
  );

  /*=== CSS Custom Font Weights ===*/
  --font-weight-light: 400;
  --font-weight-normal: 500;
  --font-weight-bold: 600;
}

/*=== General Styles ===*/
body {
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--body-background);
}

main {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/*==== Custom CSS ====*/

/*== Now Playing Section ==*/
.player__section {
  width: 23.4375rem;
  padding: 2rem;
  background: var(--player-background);
  border-radius: 0.5rem;
  box-shadow: var(--dark-box-shadow);
}
.player__now-playing {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  margin-bottom: 4rem;
}

.player__artwork {
  width: 80%;
  border-radius: 50%;
  border: 4px solid var(--grey-secondary);
  box-shadow: var(--dark-box-shadow);
  margin-bottom: 2rem;
}

.player__title {
  color: var(--white-primary);
  font-weight: var(--font-weight-bold);
}

.player__artist {
  color: var(--grey-secondary);
}

/*== Transport Controls ==*/
.player__controls {
  display: flex;
  justify-content: space-around;
  align-items: center;
  margin-bottom: 2rem;
}

.fa-solid {
  font-size: 1.5rem;
  color: var(--grey-secondary);
  cursor: pointer;
}

.fa-solid.fa-play,
.fa-solid.fa-pause {
  font-size: 3rem;
  color: var(--white-primary);
}

/*== Playback Progress ==*/
.player__progress {
  display: flex;
  flex-direction: column;
  margin-bottom: 1rem;
}

.player__time {
  display: flex;
  justify-content: space-between;
  color: var(--white-primary);
  margin-bottom: 0.5rem;
}

#progress {
  -webkit-appearance: none;
  height: 6px;
  background: var(--playlist-active-bg);
  margin: 16px 0;
  cursor: pointer;
}

#progress::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 1.2rem;
  height: 1.2rem;
  background-color: var(--white-primary);
  border-radius: 50%;
  box-shadow: var(--dark-box-shadow);
}

/*=== A/B Toggle Control ===*/
.player__ab-toggle {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  margin-bottom: 2rem;
}

.select__ab {
  width: 50px;
  height: 20px;
  background: var(--playlist-active-bg);
  border-radius: 10px;
  cursor: pointer;
  position: relative;
  transition: background 0.5s ease;
}

.select__ab.on {
  background: var(--slider-active-background);
}

.select__ab .inner {
  position: absolute;
  width: 18px;
  height: 18px;
  background: var(--button-background);
  border-radius: 50%;
  top: 1px;
  left: 1px;
  transition: left 0.2s ease;
  border: 2px solid var(--grey-secondary);
}

.select__ab.on .inner {
  left: calc(100% - 18px);
}

.player__ab-status {
  color: var(--white-primary);
  font-weight: var(--font-weight-bold);
}

/*=== Playlist ===*/
.player__playlist {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem;
  background: var(--playlist-background);
  border-radius: 0.5rem;
  box-shadow: var(--dark-box-shadow);
}

.player__playlist.hidden {
  display: none;
}

.player__playlist--button .fa-regular {
  font-size: 2rem;
  color: var(--white-primary);
  cursor: pointer;
}

.player__playlist-list {
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 100%;
  align-items: center;
  gap: 1rem;
  border-radius: 0.5rem;
}

.player__playlist-item {
  padding: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 4rem;
  background-color: var(--grey-tertiary);
  border-radius: 0.5rem;
  box-shadow: var(--dark-box-shadow);
  cursor: pointer;
  transition: background-color 0.25s ease, box-shadow 0.25s ease,
    border-left 0.25s ease;
}

.playlist__item--info {
  width: 100%;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
}

.playlist-info-title {
  font-size: 0.85rem;
  font-weight: var(--font-weight-bold);
}

.playlist-info-artist {
  font-size: 0.75rem;
}

.player-info-duration {
  font-size: 0.75rem;
}

.playlist-image {
  width: 2.5rem;
  border-radius: 5px;
  margin-right: 1rem;
}

.playlist__item--left {
  display: flex;
  flex-direction: column;
  text-align: left;
}

/*=== Hover And Focus States ===*/
.player__playlist-item:hover {
  background-color: var(--grey-secondary);
}

.player__playlist-item.active {
  border-left: 7px solid var(--slider-active-background);
}

.fa-solid:active {
  color: var(--white-primary);
}

/*=== Media Query 820px ===*/
@media (min-width: 51.25rem) {
  main {
    flex-direction: row;
  }

  .player__playlist {
    width: 23.4375rem;
  }

  .player__playlist--button {
    display: inline-block;

    transform: rotate(-90deg);
  }

  .fa-regular.fa-circle-down {
    display: inline-block;
  }
}