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

html,
body {
  width: 100%;
  height: 100%;
  overflow: hidden;
}

body {
  display: flex;
  align-items: center;
  justify-content: center;

  background-color: #000;

  color: white;
  font-family: Arial, sans-serif;
  text-align: center;
}

/* BACKGROUND */
.background {
  position: fixed;
  inset: -2%;

  background-image: url("./assets/background.png");
  background-size: 100% 100%;
  background-position: center;
  background-repeat: no-repeat;

  z-index: -1;

  animation: backgroundMovement 18s ease-in-out infinite alternate;
}

/* MOVIMENTO LENTO DO FUNDO */
@keyframes backgroundMovement {
  0% {
    transform: translate(-0.5%, 0.3%) scale(1.01);
  }

  50% {
    transform: translate(0.7%, -0.5%) scale(1.025);
  }

  100% {
    transform: translate(-0.2%, -0.3%) scale(1.015);
  }
}

/* ATMOSFERA / VINHETA */
.atmosphere {
  position: fixed;
  inset: 0;

  background:
    radial-gradient(
      circle at center,
      rgba(0, 0, 0, 0) 35%,
      rgba(0, 0, 0, 0.25) 60%,
      rgba(0, 0, 0, 0.85) 100%
    );

  pointer-events: none;
  z-index: 0;
}

/* CONTEÚDO PRINCIPAL */
main {
  position: relative;
  z-index: 1;
  padding: 24px;
}

h1 {
  font-size: clamp(42px, 8vw, 90px);
  margin-bottom: 16px;
}

p {
  font-size: clamp(18px, 3vw, 28px);
  opacity: 0.75;
}

/* CONTROLES DE ÁUDIO */
.audio-controls {
  position: fixed;
  right: 24px;
  bottom: 24px;

  display: flex;
  align-items: center;
  gap: 12px;

  padding: 10px 14px;

  background: rgba(0, 0, 0, 0.55);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 14px;

  backdrop-filter: blur(10px);

  z-index: 10;
}

/* BOTÃO MUTE */
#muteButton {
  width: 42px;
  height: 42px;

  display: flex;
  align-items: center;
  justify-content: center;

  border: 0;
  border-radius: 50%;

  background: rgba(255, 255, 255, 0.1);
  color: white;

  font-size: 20px;

  cursor: pointer;

  transition:
    background 0.2s ease,
    transform 0.2s ease;
}

#muteButton:hover {
  background: rgba(255, 255, 255, 0.18);
  transform: scale(1.05);
}

/* SLIDER DE VOLUME */
#volumeSlider {
  width: 120px;

  cursor: pointer;

  accent-color: white;
}

/* MOBILE */
@media (max-width: 700px) {
  .audio-controls {
    right: 14px;
    bottom: 14px;

    gap: 8px;

    padding: 8px 10px;
  }

  #muteButton {
    width: 38px;
    height: 38px;

    font-size: 18px;
  }

  #volumeSlider {
    width: 90px;
  }
}