/* ========================================
   RHYTHM BEASTS — Design tokens
   Marca (nav, secciones): elegante, B/N.
   Juego (canvas): vivo, colorido, orgánico.
   ======================================== */
:root {
  --color-bg: #0a0a0d;
  --color-fg: #f5f5f5;
  --color-cyan: #4de8e0;
  --color-mint: #6fffb0;
  --color-yellow: #ffe14d;
  --color-magenta: #ff3dae;
  --color-violet: #b06bff;
  --hair: rgba(245, 245, 245, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html,
body {
  background-color: var(--color-bg);
}

body {
  font-family: 'Ubuntu', sans-serif;
  color: var(--color-fg);
  margin: 0;
  overflow-x: hidden;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation: none !important; transition: none !important; }
}

/* ===== NAV ===== */
.navbar {
  background-color: rgba(10, 10, 13, 0);
  backdrop-filter: blur(0px);
  border-bottom: 1px solid transparent;
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 100;
  padding-top: 1.25rem;
  padding-bottom: 1.25rem;
  transition: background-color .35s ease, border-color .35s ease, backdrop-filter .35s ease,
              padding .35s ease;
}

.navbar.is-stuck {
  background-color: rgba(10, 10, 13, 0.85);
  backdrop-filter: blur(8px);
  border-bottom-color: var(--hair);
  padding-top: 0.85rem;
  padding-bottom: 0.85rem;
}

.navbar-brand { padding: 0; }

.logo-nav {
  height: 34px;
  width: auto;
}

.navbar-nav .nav-link {
  font-weight: 300;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.8rem;
  padding-left: 1.25rem !important;
  padding-right: 1.25rem !important;
  transition: color 0.2s ease, text-shadow 0.2s ease;
}

.navbar-nav .nav-item:nth-child(1) .nav-link { color: rgba(77, 232, 224, 0.85) !important; }
.navbar-nav .nav-item:nth-child(2) .nav-link { color: rgba(111, 255, 176, 0.85) !important; }
.navbar-nav .nav-item:nth-child(3) .nav-link { color: rgba(255, 225, 77, 0.85) !important; }
.navbar-nav .nav-item:nth-child(4) .nav-link { color: rgba(255, 61, 174, 0.85) !important; }

.navbar-nav .nav-item:nth-child(1) .nav-link:hover,
.navbar-nav .nav-item:nth-child(1) .nav-link.active {
  color: var(--color-cyan) !important;
  text-shadow: 0 0 10px rgba(77, 232, 224, 0.8);
}
.navbar-nav .nav-item:nth-child(2) .nav-link:hover,
.navbar-nav .nav-item:nth-child(2) .nav-link.active {
  color: var(--color-mint) !important;
  text-shadow: 0 0 10px rgba(111, 255, 176, 0.8);
}
.navbar-nav .nav-item:nth-child(3) .nav-link:hover,
.navbar-nav .nav-item:nth-child(3) .nav-link.active {
  color: var(--color-yellow) !important;
  text-shadow: 0 0 10px rgba(255, 225, 77, 0.8);
}
.navbar-nav .nav-item:nth-child(4) .nav-link:hover,
.navbar-nav .nav-item:nth-child(4) .nav-link.active {
  color: var(--color-magenta) !important;
  text-shadow: 0 0 10px rgba(255, 61, 174, 0.8);
}

.navbar-nav .nav-link.disabled {
  color: rgba(245, 245, 245, 0.3) !important;
  text-shadow: none;
}

.navbar-toggler { border-color: rgba(245, 245, 245, 0.3); }
.navbar-toggler-icon { filter: invert(1); }

/* ===== HERO / GAMEPLAY LOOP ===== */
.preview {
  position: relative;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  background-color: #000;
  overflow: hidden;
}

#gameplayLoop {
  display: block;
  width: 100%;
  height: 100%;
}

.stage-meta {
  position: absolute;
  bottom: 2.5rem;
  left: 2rem;
  z-index: 3;
  font-weight: 300;
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(245, 245, 245, 0.32);
  line-height: 1.9;
  pointer-events: none;
}

.stage-meta b { font-weight: 500; color: rgba(245, 245, 245, 0.7); }

.sound-toggle {
  position: absolute;
  bottom: 2.5rem;
  right: 2rem;
  z-index: 3;
  background-color: rgba(245, 245, 245, 0.08);
  border: 1px solid rgba(245, 245, 245, 0.3);
  color: var(--color-fg);
  font-family: 'Ubuntu', sans-serif;
  font-weight: 300;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  font-size: 0.75rem;
  padding: 0.6rem 1.2rem;
  border-radius: 999px;
  cursor: pointer;
  backdrop-filter: blur(6px);
  transition: background-color 0.2s ease, border-color 0.2s ease, opacity 0.3s ease;
}

.sound-toggle:hover {
  background-color: rgba(245, 245, 245, 0.16);
  border-color: rgba(245, 245, 245, 0.6);
}

.hero-fade {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 26vh;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(
    to bottom,
    rgba(10, 10, 13, 0) 0%,
    rgba(10, 10, 13, 0.25) 42%,
    rgba(10, 10, 13, 0.72) 74%,
    var(--color-bg) 100%
  );
}

.scroll-indicator {
  position: absolute;
  bottom: 2.6rem;
  left: 50%;
  transform: translateX(-50%);
  font-size: 1.3rem;
  color: rgba(245, 245, 245, 0.5);
  animation: bounce 2.4s ease-in-out infinite;
  z-index: 2;
  transition: opacity 0.4s ease;
}

@keyframes bounce {
  0%, 100% { transform: translate(-50%, 0); opacity: 0.35; }
  50% { transform: translate(-50%, 10px); opacity: 0.9; }
}

/* ===== SECCIONES ===== */
.panel {
  position: relative;
  padding: 9rem 0;
  border-top: 1px solid var(--hair);
  background-color: var(--color-bg);
}

#sinopsis {
  border-top: none;
  padding-top: 7rem;
}

.panel-inner {
  width: min(1080px, 88vw);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 7rem minmax(0, 1fr);
  column-gap: 3rem;
  align-items: start;
}

.panel-index {
  font-weight: 300;
  font-size: 0.75rem;
  letter-spacing: 0.3em;
  color: var(--accent, var(--color-fg));
  opacity: 0.55;
  margin: 0.6rem 0 0;
  grid-row: 1;
}

.panel-title {
  grid-column: 2;
  grid-row: 1;
  font-weight: 300;
  font-size: clamp(2.2rem, 6vw, 4.2rem);
  letter-spacing: 0.02em;
  margin: 0 0 2.5rem;
  line-height: 1;
}

.panel-body {
  grid-column: 2;
  grid-row: 2;
  max-width: 62ch;
}

.panel-body p {
  font-weight: 300;
  font-size: 1.02rem;
  line-height: 1.85;
  color: rgba(245, 245, 245, 0.62);
  margin: 0 0 1.4rem;
}

.panel-body .lead {
  font-size: clamp(1.15rem, 2.4vw, 1.5rem);
  font-weight: 300;
  line-height: 1.55;
  color: var(--color-fg);
  margin-bottom: 2rem;
  padding-left: 1.25rem;
  border-left: 1px solid var(--accent, var(--color-fg));
}

.panel--cyan { --accent: var(--color-cyan); }
.panel--mint { --accent: var(--color-mint); }
.panel--yellow { --accent: var(--color-yellow); }
.panel--magenta { --accent: var(--color-magenta); }

/* revelado al hacer scroll */
.panel-inner > * {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.2, 0.7, 0.3, 1);
}
.panel.is-visible .panel-inner > * { opacity: 1; transform: none; }
.panel.is-visible .panel-title { transition-delay: 0.06s; }
.panel.is-visible .panel-body { transition-delay: 0.12s; }

/* paleta */
.swatches {
  list-style: none;
  padding: 0;
  margin: 2.5rem 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 1.75rem;
  font-size: 0.72rem;
  font-weight: 300;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(245, 245, 245, 0.5);
}

.swatches li { display: flex; align-items: center; gap: 0.6rem; }

.dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c);
  box-shadow: 0 0 12px var(--c);
}

/* modos */
.modes {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1px;
  background: var(--hair);
  border: 1px solid var(--hair);
}

.mode {
  background: var(--color-bg);
  padding: 2rem 1.75rem;
  transition: background-color 0.3s ease;
}

.mode:hover { background: #101017; }

.mode h3 {
  font-weight: 400;
  font-size: 0.82rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent, var(--color-fg));
  margin: 0 0 1rem;
}

.mode p {
  font-weight: 300;
  font-size: 0.92rem;
  line-height: 1.8;
  color: rgba(245, 245, 245, 0.55);
  margin: 0;
}

/* ===== FOOTER ===== */
.site-footer {
  background-color: var(--color-bg);
  border-top: 1px solid var(--hair);
  padding: 4rem 2rem 3rem;
  text-align: center;
}

.logo-footer { height: 26px; opacity: 0.5; }

.site-footer p {
  margin: 1.5rem 0 0;
  font-weight: 300;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(245, 245, 245, 0.28);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .navbar { background-color: rgba(10, 10, 13, 0.85); backdrop-filter: blur(8px); }
  .panel { padding: 6rem 0; }
  .panel-inner { grid-template-columns: 1fr; row-gap: 0; }
  .panel-index { grid-column: 1; margin-bottom: 1rem; }
  .panel-title { grid-column: 1; grid-row: auto; margin-bottom: 1.8rem; }
  .panel-body { grid-column: 1; grid-row: auto; }
  .stage-meta { bottom: 1.5rem; left: 1.25rem; }
  .sound-toggle { bottom: 1.5rem; right: 1.25rem; }
  .scroll-indicator { bottom: 1.6rem; }
}