/* ============================================================================
   DUET · Base + Fundo Aurora (poeira estelar em movimento)
   Depende de tokens.css.
   ============================================================================ */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--duet-font-body);
  font-size: var(--duet-fs-body);
  line-height: var(--duet-lh-body);
  color: var(--duet-text);
  background: var(--duet-void);
  position: relative;
  overflow-x: hidden;
}

/* ----------------------------------------------------------------------------
   FUNDO AURORA
   Camada 0: preto espacial (gradiente radial, sem estrelas).
   Camada 1-2: manchas de nebulosa (aurora) que derivam lentamente.
   Camada 3: leve grão de "poeira" para evitar banding e dar textura premium.
   Aplicar a classe .duet-aurora-bg no <body> ou num wrapper full-screen.
---------------------------------------------------------------------------- */
.duet-aurora-bg {
  background:
    radial-gradient(120% 80% at 50% -10%, #12182e 0%, transparent 60%),
    radial-gradient(100% 100% at 50% 120%, var(--duet-space-800) 0%, var(--duet-void) 70%);
  background-color: var(--duet-void);
}

.duet-aurora-bg::before,
.duet-aurora-bg::after {
  content: "";
  position: fixed;
  inset: -30vmax;
  z-index: -2;
  pointer-events: none;
  will-change: transform, opacity;
}

/* Aurora principal — teal/cyan/violet derivando */
.duet-aurora-bg::before {
  background:
    radial-gradient(35vmax 28vmax at 25% 30%, rgba(53, 230, 197, 0.28), transparent 60%),
    radial-gradient(40vmax 30vmax at 75% 25%, rgba(58, 168, 255, 0.24), transparent 62%),
    radial-gradient(45vmax 34vmax at 60% 80%, rgba(139, 92, 246, 0.26), transparent 60%),
    radial-gradient(30vmax 26vmax at 15% 75%, rgba(225, 95, 208, 0.16), transparent 60%);
  filter: blur(30px) saturate(120%);
  animation: duet-aurora-drift var(--duet-aurora-duration) var(--duet-ease-in-out) infinite alternate;
}

/* Segunda camada, mais lenta e deslocada, cria profundidade "star dust" */
.duet-aurora-bg::after {
  background:
    radial-gradient(38vmax 30vmax at 80% 60%, rgba(68, 54, 184, 0.22), transparent 60%),
    radial-gradient(30vmax 24vmax at 40% 15%, rgba(124, 243, 224, 0.12), transparent 60%);
  filter: blur(40px) saturate(115%);
  opacity: 0.9;
  animation: duet-aurora-drift-alt calc(var(--duet-aurora-duration) * 1.5)
    var(--duet-ease-in-out) infinite alternate;
}

@keyframes duet-aurora-drift {
  0% {
    transform: translate3d(-4%, -2%, 0) rotate(0deg) scale(1.05);
  }
  50% {
    transform: translate3d(3%, 2%, 0) rotate(6deg) scale(1.15);
  }
  100% {
    transform: translate3d(-2%, 4%, 0) rotate(-4deg) scale(1.08);
  }
}

@keyframes duet-aurora-drift-alt {
  0% {
    transform: translate3d(3%, 3%, 0) rotate(0deg) scale(1.1);
  }
  100% {
    transform: translate3d(-3%, -3%, 0) rotate(8deg) scale(1.2);
  }
}

/* Grão de poeira fino sobre tudo (sutil, ajuda a esconder banding) */
.duet-aurora-bg > .duet-dust-grain,
.duet-dust-grain {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.05;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ----------------------------------------------------------------------------
   TIPOGRAFIA
---------------------------------------------------------------------------- */
h1, h2, h3, h4, .duet-heading {
  font-family: var(--duet-font-heading);
  font-weight: 500;
  line-height: var(--duet-lh-tight);
  letter-spacing: 0.01em;
  margin: 0 0 var(--duet-space-4);
}

.duet-display {
  font-family: var(--duet-font-heading);
  font-size: var(--duet-fs-display);
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.01em;
  margin: 0;
}

h1 { font-size: var(--duet-fs-h1); }
h2 { font-size: var(--duet-fs-h2); }
h3 { font-size: var(--duet-fs-h3); }

p { margin: 0 0 var(--duet-space-4); color: var(--duet-text-muted); }

a { color: var(--duet-glow); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Links que SÃO componentes (botões, cards, chips, nav, avisos) nunca
   sublinham no hover — o sublinhado é só para links de texto inline. */
a.duet-btn,
a.duet-glass,
a.duet-chip,
a.duet-nav-item,
a.duet-ai-note,
a:has(.duet-glass),
a:has(> .duet-btn) {
  text-decoration: none;
}
a.duet-btn:hover,
a.duet-glass:hover,
a.duet-chip:hover,
a.duet-nav-item:hover,
a.duet-ai-note:hover,
a:has(.duet-glass):hover,
a:has(> .duet-btn):hover {
  text-decoration: none;
}

/* Texto com preenchimento em gradiente aurora */
.duet-text-aurora {
  background: var(--duet-gradient-aurora);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* Utilidades de layout mínimas para o showcase */
.duet-container { width: min(1080px, 92vw); margin-inline: auto; }
.duet-stack > * + * { margin-top: var(--duet-space-4); }

/* ----------------------------------------------------------------------------
   SEÇÕES · variações de fundo
   Aplique uma destas classes a um <section> para trocar o "clima" da seção.
   Todas mantêm o texto legível no tema dark.
---------------------------------------------------------------------------- */

/* a) Aurora boreal — gradiente colorido, vivo, com leve movimento */
.duet-section--aurora {
  position: relative;
  background: var(--duet-gradient-aurora);
  background-size: 200% 200%;
  animation: duet-section-aurora-shift var(--duet-aurora-duration) var(--duet-ease-in-out) infinite alternate;
  color: var(--duet-text);
  overflow: hidden;
}
/* Escurece a aurora por baixo do conteúdo para manter contraste premium */
.duet-section--aurora::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 6, 10, 0.55), rgba(5, 6, 10, 0.78));
  pointer-events: none;
}
.duet-section--aurora > * { position: relative; z-index: 1; }

@keyframes duet-section-aurora-shift {
  0% { background-position: 0% 50%; }
  100% { background-position: 100% 50%; }
}

/* b) Cor chapada — superfície sólida, calma, sem gradiente */
.duet-section--flat { background: var(--duet-space-800); color: var(--duet-text); }
.duet-section--flat-deep { background: var(--duet-space-900); color: var(--duet-text); }
.duet-section--flat-ink { background: var(--duet-void); color: var(--duet-text); }

/* c) Espaço — gradiente preto/cinza, profundo, sem cor */
.duet-section--space {
  background:
    radial-gradient(120% 90% at 50% 0%, #20232e 0%, transparent 55%),
    linear-gradient(180deg, var(--duet-space-800) 0%, var(--duet-void) 100%);
  color: var(--duet-text);
}
.duet-section--space-soft {
  background: linear-gradient(160deg, #171922 0%, #0b0d15 60%, var(--duet-void) 100%);
  color: var(--duet-text);
}

/* ----------------------------------------------------------------------------
   TRANSIÇÃO BORRADA ENTRE SEÇÕES
   Em vez de um corte seco, as seções se dissolvem uma na outra.
   Duas formas:

   a) .duet-section--feather : a seção esmaece nas bordas (topo/baixo),
      deixando o fundo aparecer atrás — bom sobre .duet-aurora-bg.
   b) .duet-seam : um elemento fino colocado ENTRE duas seções, com blur,
      que mistura visualmente as duas superfícies.
---------------------------------------------------------------------------- */

/* (a) esmaece as bordas da própria seção com máscara */
.duet-section--feather {
  -webkit-mask-image: linear-gradient(
    to bottom,
    transparent 0,
    #000 8%,
    #000 92%,
    transparent 100%
  );
  mask-image: linear-gradient(
    to bottom,
    transparent 0,
    #000 8%,
    #000 92%,
    transparent 100%
  );
}

/* (b) costura borrada entre seções: coloque <div class="duet-seam"></div>
   logo depois de uma seção e antes da próxima. */
.duet-seam {
  position: relative;
  height: 96px;
  margin-top: -48px;
  margin-bottom: -48px;
  z-index: 5;
  pointer-events: none;
  /* o próprio seam é transparente; o blur vem do backdrop das seções vizinhas */
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
  -webkit-mask-image: linear-gradient(to bottom, transparent, #000 50%, transparent);
  mask-image: linear-gradient(to bottom, transparent, #000 50%, transparent);
}