/* =========================================================================
   HypnaState — v2
   Monochrome base · one themeable accent · cinematic scroll reveals
   ========================================================================= */

:root {
  --bg: #000000;

  --fg:       rgba(245, 245, 245, 0.94);
  --fg-dim:   rgba(210, 210, 210, 0.58);
  --fg-faint: rgba(180, 180, 180, 0.30);

  --line:        rgba(255, 255, 255, 0.07);
  --line-strong: rgba(255, 255, 255, 0.18);
  --line-bright: rgba(255, 255, 255, 0.45);

  /* Accent — overridden at runtime by ColorPresets (themes). Default: candle. */
  --accent:        #e8c07a;
  --accent-soft:   #f2d6a0;
  --accent-glow:   rgba(232, 192, 122, 0.42);
  --accent-glow-2: rgba(232, 192, 122, 0.18);

  --green:     #00ff9d;
  --green-dim: #00b873;
  --danger:    #ff4d6d;

  --glass:        rgba(10, 10, 10, 0.55);
  --glass-strong: rgba(14, 14, 14, 0.72);

  --radius: 14px;
  --radius-lg: 22px;
  --t: cubic-bezier(0.2, 0.7, 0.2, 1);

  --font-sans: "Space Grotesk", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-display: "Manrope", "Space Grotesk", ui-sans-serif, system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
}

* { box-sizing: border-box; }
*::selection { background: var(--accent-glow); color: #fff; }

html { scroll-behavior: smooth; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  font-weight: 400;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

body {
  min-height: 100dvh;
  background:
    radial-gradient(1100px 600px at 50% -10%, rgba(255, 255, 255, 0.045), transparent 60%),
    radial-gradient(900px 500px at 50% 110%, var(--accent-glow-2), transparent 60%),
    var(--bg);
}

img, svg { display: block; }
a { color: inherit; }
button { font-family: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
input, textarea { font-family: inherit; color: inherit; }

.visually-hidden {
  position: absolute !important;
  clip: rect(0 0 0 0);
  height: 1px; width: 1px;
  overflow: hidden;
  white-space: nowrap;
}

/* =========================================================================
   Background
   ========================================================================= */
.bg-layer { position: fixed; inset: 0; z-index: 0; pointer-events: none; overflow: hidden; }

.bg-grid {
  position: absolute;
  inset: -2px;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 64px 64px, 64px 64px;
  mask-image: radial-gradient(ellipse at 50% 35%, #000 22%, transparent 72%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 35%, #000 22%, transparent 72%);
  animation: gridDrift 80s linear infinite;
  will-change: background-position;
}
@keyframes gridDrift {
  from { background-position: 0 0, 0 0; }
  to { background-position: 64px 64px, 64px 64px; }
}

.bg-glow {
  position: absolute;
  top: 38%;
  left: 50%;
  width: 1200px;
  height: 1200px;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(255, 255, 255, 0.05) 0%, var(--accent-glow-2) 25%, transparent 60%);
  filter: blur(30px);
  animation: glowPulse 10s ease-in-out infinite;
  will-change: opacity;
}
@keyframes glowPulse {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

.bg-scanline {
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    180deg,
    transparent 0,
    transparent 3px,
    rgba(255, 255, 255, 0.01) 3px,
    rgba(255, 255, 255, 0.01) 4px
  );
  mix-blend-mode: screen;
  pointer-events: none;
}

/* =========================================================================
   HUD
   ========================================================================= */
.hud {
  position: fixed;
  top: max(18px, env(safe-area-inset-top));
  left: max(18px, env(safe-area-inset-left));
  z-index: 10;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--fg-dim);
  display: flex;
  flex-direction: column;
  gap: 6px;
  user-select: none;
}
.hud-right {
  left: auto;
  right: max(18px, env(safe-area-inset-right));
  text-align: right;
  align-items: flex-end;
}
.hud-row { display: inline-flex; align-items: center; gap: 8px; }
.hud-key { color: var(--fg-faint); margin-right: 8px; }
.hud-val { color: var(--fg); font-variant-numeric: tabular-nums; }
.hud-label { text-transform: uppercase; }
.hud-link {
  color: var(--fg-dim);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  padding-bottom: 1px;
  transition: color .2s var(--t), border-color .2s var(--t);
}
.hud-link:hover { color: var(--accent-soft); border-color: var(--accent); }

.led {
  width: 8px; height: 8px; border-radius: 50%;
  background: #0c2820;
  box-shadow: inset 0 0 2px rgba(0, 0, 0, 0.6);
  display: inline-block; position: relative; flex-shrink: 0;
}
.led[data-on="true"] {
  background: var(--green);
  box-shadow:
    0 0 6px rgba(0, 255, 157, 0.8),
    0 0 14px rgba(0, 255, 157, 0.45),
    inset 0 0 2px rgba(255, 255, 255, 0.4);
  animation: ledBlink 2.2s ease-in-out infinite;
}
.led-sm { width: 6px; height: 6px; }
@keyframes ledBlink {
  0%, 60%, 100% { opacity: 1; }
  70% { opacity: 0.35; }
  80% { opacity: 1; }
}

/* =========================================================================
   Stage / shared section layout
   ========================================================================= */
.stage {
  position: relative;
  z-index: 1;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 clamp(20px, 4vw, 56px);
}

.section {
  padding: clamp(80px, 12vh, 140px) 0;
  scroll-margin-top: 60px;
}

.section-head {
  display: grid;
  gap: 10px;
  max-width: 720px;
  margin-bottom: 28px;
}
.section-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  color: var(--accent);
  text-transform: uppercase;
}
.section-head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.8rem, 3.6vw, 2.6rem);
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: #fff;
}
.section-head p {
  margin: 0;
  color: var(--fg-dim);
  font-size: 1rem;
  max-width: 56ch;
}

/* Cinematic scroll-reveal — sections start dim and rise from black */
.reveal {
  opacity: 0.06;
  transform: translateY(28px);
  transition: opacity 1.1s var(--t), transform 1.1s var(--t);
  will-change: opacity, transform;
}
.reveal.is-revealed {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* =========================================================================
   HERO — full-bleed, left-aligned monumental title + giant visualizer
   ========================================================================= */
.hero {
  /* svh is the *small* viewport height — it ignores the show/hide of mobile
     browser chrome, which would otherwise relayout the hero every time the
     address bar slides. Falls back to dvh, then vh. */
  min-height: 100vh;
  min-height: 100dvh;
  min-height: 100svh;
  padding: clamp(100px, 14vh, 160px) 0 80px;
  display: grid;
  align-content: center;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: clamp(32px, 5vw, 80px);
  align-items: center;
}

.hero-text { display: grid; gap: 22px; align-content: center; animation: rise 1.1s var(--t) both; }

.title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(3.6rem, 11vw, 9rem);
  letter-spacing: -0.055em;
  line-height: 0.86;
  color: #fff;
  text-transform: none;
  display: grid;
  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.03);
}
.title-line { display: block; }
.title-dot {
  color: var(--accent);
  text-shadow: 0 0 22px var(--accent-glow);
  margin-left: 0.04em;
}

.typing {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(0.95rem, 1.6vw, 1.05rem);
  letter-spacing: 0.04em;
  color: var(--fg-dim);
  /* Reserve enough vertical space for the longest line, even if it wraps to
     two lines on narrow screens. Without this, the container height changes
     as text is typed/deleted, which pumps the rest of the page up and down. */
  min-height: 3.4em;
  display: block;
  font-variant-ligatures: none;
  contain: layout style;
}
.typing-caret {
  display: inline-block;
  width: 0.55ch;
  height: 1.1em;
  margin-left: 2px;
  background: var(--accent);
  vertical-align: -2px;
  animation: caretBlink 1.05s steps(1, end) infinite;
  box-shadow: 0 0 8px var(--accent-glow);
}
@keyframes caretBlink {
  0%, 50% { opacity: 1; }
  51%, 100% { opacity: 0; }
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--fg-faint);
}
.meta-pill {
  padding: 4px 10px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--fg);
}
.meta-sep { opacity: 0.5; }

.brand-nav {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--fg-faint);
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}
.brand-nav a {
  color: var(--fg-dim);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 255, 255, 0.18);
  padding-bottom: 2px;
  transition: color .2s var(--t), border-color .2s var(--t);
}
.brand-nav a:hover { color: var(--accent-soft); border-color: var(--accent); }
.brand-nav-sep { opacity: 0.5; }

@keyframes rise {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: none; }
}

/* Hero stage (visualizer + transport) */
.hero-stage {
  display: grid;
  gap: 30px;
  justify-items: center;
  animation: rise 1.4s var(--t) both;
}

/* Bigger DRIFT */
.visualizer {
  position: relative;
  width: clamp(260px, 38vw, 380px);
  aspect-ratio: 1 / 1;
  display: grid;
  place-items: center;
}
.visualizer.is-hero {
  width: clamp(280px, 42vw, 520px);
}

/* Ambient halo anchored to the visualizer. Lives behind everything in its
   parent stacking context. Pulses softly; brightens slightly when audio
   engages. Kept very faint by design — the candle, not the spotlight. */
.visualizer::before {
  content: "";
  position: absolute;
  inset: -120%;
  border-radius: 50%;
  background: radial-gradient(
    closest-side,
    rgba(255, 255, 255, 0.04) 0%,
    rgba(232, 192, 122, 0.11) 24%,
    transparent 63%
  );
  filter: blur(44px);
  pointer-events: none;
  z-index: -1;
  opacity: 0.6;
  animation: visualizerHalo 12s ease-in-out infinite;
  will-change: opacity;
  transform: translateZ(0);
}
.visualizer.is-playing::before {
  background: radial-gradient(
    closest-side,
    rgba(255, 255, 255, 0.06) 0%,
    var(--accent-glow-2) 26%,
    transparent 62%
  );
  animation: visualizerHaloActive 7s ease-in-out infinite;
}
@keyframes visualizerHalo {
  0%, 100% { opacity: 0.5; }
  50%      { opacity: 0.7; }
}
@keyframes visualizerHaloActive {
  0%, 100% { opacity: 0.75; }
  50%      { opacity: 0.95; }
}

.ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  opacity: 0.6;
  pointer-events: none;
  transition: border-color .6s var(--t), box-shadow .6s var(--t);
}
.ring-2 { inset: 10%; opacity: 0.42; }
.ring-3 { inset: 22%; opacity: 0.3; border-style: dashed; }
.ring-4 { inset: 34%; opacity: 0.2; }

.visualizer.is-playing .ring   { border-color: var(--accent-glow); }
.visualizer.is-playing .ring-3 { border-color: var(--accent-glow); opacity: 0.5; }
.visualizer.is-playing .ring-1 { box-shadow: 0 0 32px var(--accent-glow-2); }

.visualizer .ring-1 { animation: ringPulse 250ms ease-in-out infinite alternate; }
.visualizer .ring-2 { animation: ringPulse 250ms ease-in-out infinite alternate-reverse; }
.visualizer .ring-3 { animation: spinSlow 60s linear infinite; }
@keyframes ringPulse {
  from { transform: scale(1); }
  to   { transform: scale(1.03); }
}
@keyframes spinSlow { to { transform: rotate(360deg); } }

.visualizer:not(.is-playing) .ring-1,
.visualizer:not(.is-playing) .ring-2 {
  animation-play-state: paused;
}

.core {
  position: relative;
  width: 42%;
  height: 42%;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: radial-gradient(circle at 50% 40%, rgba(255, 255, 255, 0.05), rgba(0, 0, 0, 0.6) 70%);
  border: 1px solid var(--line-strong);
  box-shadow: inset 0 0 18px rgba(255, 255, 255, 0.03);
  transition: box-shadow .5s var(--t), border-color .5s var(--t), background .5s var(--t);
}
.visualizer.is-playing .core {
  background: radial-gradient(circle at 50% 40%, var(--accent-glow), rgba(0, 0, 0, 0.6) 70%);
  border-color: var(--accent);
  box-shadow:
    inset 0 0 30px var(--accent-glow),
    0 0 55px var(--accent-glow);
  animation: corePulse 250ms ease-in-out infinite alternate;
}
@keyframes corePulse {
  from { transform: scale(1); }
  to { transform: scale(1.04); }
}

.core-label {
  font-family: var(--font-mono);
  font-size: clamp(11px, 1.1vw, 13px);
  letter-spacing: 0.32em;
  color: var(--fg-dim);
  transition: color .4s var(--t), text-shadow .4s var(--t);
}
.visualizer.is-playing .core-label {
  color: var(--accent-soft);
  text-shadow: 0 0 12px var(--accent-glow);
}

.wave-canvas {
  position: absolute;
  inset: 0;
  width: 100%; height: 100%;
  border-radius: 50%;
  pointer-events: none;
  opacity: 0.9;
}

/* Hero transport */
.hero-transport {
  width: 100%;
  max-width: 440px;
  display: grid;
  gap: 22px;
  justify-items: center;
}

.play-btn {
  position: relative;
  height: 60px;
  padding: 0 28px 0 22px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: rgba(255, 255, 255, 0.02);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.24em;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-transform: uppercase;
  transition: transform .25s var(--t), border-color .25s var(--t), box-shadow .25s var(--t), background .25s var(--t), color .25s var(--t);
}
.play-btn:hover {
  transform: translateY(-1px);
  border-color: var(--line-bright);
  background: rgba(255, 255, 255, 0.04);
}
.play-btn:active { transform: translateY(0); }
.play-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }

.play-icon {
  width: 30px; height: 30px;
  display: grid; place-items: center;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  transition: color .25s var(--t), border-color .25s var(--t);
}
.play-icon .icon-pause { display: none; }
.play-btn[aria-pressed="true"] .icon-play { display: none; }
.play-btn[aria-pressed="true"] .icon-pause { display: inline; }
.play-btn[aria-pressed="true"] {
  color: var(--accent-soft);
  border-color: var(--accent);
  background: var(--accent-glow-2);
  box-shadow: 0 0 0 1px var(--accent-glow-2), 0 0 50px -10px var(--accent-glow);
}
.play-btn[aria-pressed="true"] .play-icon {
  color: var(--accent);
  border-color: var(--accent);
}

.slider-block { width: 100%; display: grid; gap: 10px; }
.slider-label {
  display: flex; justify-content: space-between; align-items: baseline;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--fg-dim);
}
.slider-value { color: var(--fg); font-variant-numeric: tabular-nums; }

input[type="range"] {
  -webkit-appearance: none; appearance: none;
  width: 100%; background: transparent; cursor: pointer; height: 28px;
}
input[type="range"]:focus { outline: none; }
input[type="range"]:focus-visible::-webkit-slider-thumb { box-shadow: 0 0 0 3px var(--accent-glow-2), 0 0 12px var(--accent-glow); }
input[type="range"]:focus-visible::-moz-range-thumb     { box-shadow: 0 0 0 3px var(--accent-glow-2), 0 0 12px var(--accent-glow); }
input[type="range"]::-webkit-slider-runnable-track {
  height: 2px;
  background: linear-gradient(90deg, var(--accent) 0%, var(--accent) var(--p, 10%), rgba(255, 255, 255, 0.14) var(--p, 10%), rgba(255, 255, 255, 0.14) 100%);
  border-radius: 999px;
}
input[type="range"]::-moz-range-track { height: 2px; background: rgba(255, 255, 255, 0.14); border-radius: 999px; }
input[type="range"]::-moz-range-progress { height: 2px; background: var(--accent); border-radius: 999px; }
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 16px; height: 16px; border-radius: 50%;
  background: #0c0a06; border: 1px solid var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
  margin-top: -7px; transition: transform .15s var(--t);
}
input[type="range"]::-moz-range-thumb {
  width: 16px; height: 16px; border-radius: 50%;
  background: #0c0a06; border: 1px solid var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.15); }

/* Scroll hint */
.scroll-hint {
  position: absolute;
  bottom: 24px;
  left: 0;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.3em;
  color: var(--fg-faint);
  text-transform: uppercase;
  text-decoration: none;
  transition: color .2s var(--t);
}
.scroll-hint:hover { color: var(--accent-soft); }
.scroll-arrow {
  display: inline-block;
  animation: scrollBob 2.2s ease-in-out infinite;
}
@keyframes scrollBob {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(4px); }
}

/* =========================================================================
   Glass surface primitive
   ========================================================================= */
.glass {
  position: relative;
  background: var(--glass);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(14px) saturate(120%);
  -webkit-backdrop-filter: blur(14px) saturate(120%);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.04),
    0 30px 80px -40px rgba(0, 0, 0, 0.7);
}
.glass::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background:
    linear-gradient(90deg, var(--line-bright), transparent 40%) top left/40px 1px no-repeat,
    linear-gradient(270deg, var(--line-bright), transparent 40%) top right/40px 1px no-repeat,
    linear-gradient(90deg, var(--line-bright), transparent 40%) bottom left/40px 1px no-repeat,
    linear-gradient(270deg, var(--line-bright), transparent 40%) bottom right/40px 1px no-repeat,
    linear-gradient(180deg, var(--line-bright), transparent 40%) top left/1px 40px no-repeat,
    linear-gradient(180deg, var(--line-bright), transparent 40%) top right/1px 40px no-repeat,
    linear-gradient(0deg, var(--line-bright), transparent 40%) bottom left/1px 40px no-repeat,
    linear-gradient(0deg, var(--line-bright), transparent 40%) bottom right/1px 40px no-repeat;
  opacity: 0.75;
}

/* =========================================================================
   Presets
   ========================================================================= */
.preset-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px;
}

.preset {
  position: relative;
  padding: 18px 18px 20px;
  text-align: left;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.015);
  transition: transform .25s var(--t), border-color .25s var(--t), box-shadow .25s var(--t), background .25s var(--t);
  cursor: pointer;
  display: grid;
  gap: 8px;
  overflow: hidden;
}
.preset:hover {
  transform: translateY(-2px);
  border-color: var(--line-strong);
  background: rgba(255, 255, 255, 0.03);
}
.preset.is-active {
  border-color: var(--accent);
  background: var(--accent-glow-2);
  box-shadow: 0 0 0 1px var(--accent-glow-2) inset, 0 16px 50px -30px var(--accent-glow);
}
.preset-tag {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.24em;
  color: var(--fg-faint);
}
.preset.is-active .preset-tag { color: var(--accent-soft); }
.preset-name {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.005em;
  color: #fff;
}
.preset-desc { color: var(--fg-dim); font-size: 0.88rem; line-height: 1.5; }
.preset-stats {
  margin-top: 6px;
  display: flex;
  gap: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--fg-faint);
}
.preset-stats b { color: var(--fg); font-weight: 500; }
.preset.is-active .preset-stats b { color: var(--accent-soft); }

.preset-delete {
  position: absolute;
  top: 8px;
  right: 8px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  display: grid; place-items: center;
  font-size: 14px;
  color: var(--fg-faint);
  border: 1px solid transparent;
  opacity: 0;
  transition: opacity .2s var(--t), color .2s var(--t), border-color .2s var(--t), background .2s var(--t);
}
.preset:hover .preset-delete { opacity: 1; }
.preset-delete:hover {
  color: var(--danger);
  border-color: var(--danger);
  background: rgba(255, 77, 109, 0.06);
}

.subsection { margin-top: 30px; }
.subsection-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
  flex-wrap: wrap;
  gap: 12px;
}
.subsection-head-left {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.subsection-head h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.005em;
  color: var(--fg);
}
.subsection-empty {
  color: var(--fg-faint);
  font-size: 0.9rem;
  margin: 0;
  padding: 16px 18px;
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius);
}
.subsection-empty.is-hidden { display: none; }

.subsection-hint {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--fg-faint);
}

/* Save-as-preset row — anchored under the manual tuning panel */
.save-preset-row {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}
.save-preset-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 26px;
  border-radius: 999px;
  border: 1px solid var(--accent);
  background: var(--accent-glow-2);
  color: var(--accent-soft);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  cursor: pointer;
  transition: transform .2s var(--t), background .2s var(--t), box-shadow .2s var(--t);
}
.save-preset-btn:hover {
  transform: translateY(-2px);
  background: var(--accent-glow);
  box-shadow: 0 16px 40px -20px var(--accent-glow);
}
.save-preset-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
.save-preset-btn.is-saving .led {
  background: var(--accent);
  box-shadow: 0 0 6px var(--accent-glow), 0 0 14px var(--accent-glow-2);
  animation: none;
}
.save-preset-hint {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--fg-faint);
  text-align: center;
  transition: color .2s var(--t);
}
.save-preset-hint.is-saved { color: var(--green-dim); }

/* Live-edit indicator (mirrors journal saved-indicator) */
.edit-indicator {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px;
  border: 1px solid var(--accent-glow-2);
  border-radius: 999px;
  background: var(--accent-glow-2);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent-soft);
}
.edit-indicator[hidden] { display: none !important; }
.edit-indicator.is-saving .led { background: var(--accent); box-shadow: 0 0 6px var(--accent-glow), 0 0 14px var(--accent-glow-2); animation: none; }

/* Manual tuning panel */
.tuning-panel {
  margin-top: 30px;
  padding: clamp(22px, 3vw, 32px);
  display: grid;
  gap: 22px;
}
.tuning-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 16px;
  flex-wrap: wrap;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}
.tuning-head h3 {
  margin: 6px 0 4px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.2rem, 2.2vw, 1.5rem);
  letter-spacing: -0.015em;
  color: #fff;
}
.tuning-head p {
  margin: 0;
  color: var(--fg-dim);
  font-size: 0.92rem;
  max-width: 50ch;
}
.tuning-help {
  color: var(--fg-dim);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 255, 255, 0.18);
  padding-bottom: 2px;
  transition: color .2s var(--t), border-color .2s var(--t);
  white-space: nowrap;
}
.tuning-help:hover { color: var(--accent-soft); border-color: var(--accent); }

.tuning-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
}

.tuning-hint {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--fg-faint);
  text-transform: uppercase;
  margin-top: -2px;
}

.tuning-section { display: grid; gap: 12px; }
.tuning-section-label { margin-bottom: 2px; }

/* Noise type picker — segmented chips */
.noise-picker {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.noise-chip {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  padding: 9px 16px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--fg-dim);
  cursor: pointer;
  transition: color .2s var(--t), border-color .2s var(--t), background .2s var(--t), box-shadow .2s var(--t);
  background: rgba(255, 255, 255, 0.015);
}
.noise-chip:hover {
  color: var(--fg);
  border-color: var(--line-bright);
  background: rgba(255, 255, 255, 0.03);
}
.noise-chip.is-active {
  color: var(--accent-soft);
  border-color: var(--accent);
  background: var(--accent-glow-2);
  box-shadow: 0 0 24px -8px var(--accent-glow);
}

/* Ghost button */
.ghost-btn {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--fg-dim);
  padding: 8px 14px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  text-transform: uppercase;
  transition: color .2s var(--t), border-color .2s var(--t), background .2s var(--t);
  cursor: pointer;
}
.ghost-btn:hover { color: var(--accent-soft); border-color: var(--accent); background: var(--accent-glow-2); }
.ghost-btn.danger:hover { color: var(--danger); border-color: var(--danger); background: rgba(255, 77, 109, 0.04); }

/* =========================================================================
   Color theme picker
   ========================================================================= */
.theme-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
}
.theme-card {
  position: relative;
  padding: 18px;
  text-align: left;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.015);
  transition: transform .25s var(--t), border-color .25s var(--t), background .25s var(--t);
  cursor: pointer;
  display: grid;
  gap: 12px;
}
.theme-card:hover { transform: translateY(-2px); border-color: var(--line-strong); background: rgba(255, 255, 255, 0.03); }
.theme-card.is-active {
  border-color: var(--accent);
  background: var(--accent-glow-2);
}
.theme-swatch {
  display: flex;
  align-items: center;
  gap: 10px;
}
.theme-dot {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.18);
  box-shadow: 0 0 14px currentColor;
}
.theme-name {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1rem;
  color: #fff;
  letter-spacing: -0.005em;
}
.theme-desc {
  color: var(--fg-dim);
  font-size: 0.84rem;
  line-height: 1.5;
}
.theme-check {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--fg-faint);
}
.theme-card.is-active .theme-check { color: var(--accent-soft); }

/* =========================================================================
   Notebooks (multi-journal)
   ========================================================================= */
.tabbar {
  display: flex;
  align-items: stretch;
  border-bottom: 1px solid var(--line);
  background: rgba(0, 0, 0, 0.35);
  overflow: hidden;
}
.tabbar-tabs {
  display: flex;
  flex: 1;
  min-width: 0;
  overflow-x: auto;
  scrollbar-width: thin;
}
.tabbar-tabs::-webkit-scrollbar { height: 4px; }
.tabbar-tabs::-webkit-scrollbar-thumb { background: rgba(255, 255, 255, 0.1); border-radius: 2px; }

.tab {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 18px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--fg-dim);
  border-right: 1px solid var(--line);
  border-bottom: 2px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  transition: color .2s var(--t), background .2s var(--t), border-color .2s var(--t);
  flex-shrink: 0;
}
.tab:hover { color: var(--fg); background: rgba(255, 255, 255, 0.02); }
.tab.is-active {
  color: var(--accent-soft);
  background: rgba(255, 255, 255, 0.025);
  border-bottom-color: var(--accent);
}
.tab-count {
  font-size: 9px;
  color: var(--fg-faint);
  letter-spacing: 0.1em;
}
.tab.is-active .tab-count { color: var(--accent); }

.tab-actions {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-left: 4px;
  opacity: 0;
  transition: opacity .2s var(--t);
}
.tab.is-active .tab-actions { opacity: 1; }
.tab-action {
  width: 18px; height: 18px;
  display: grid; place-items: center;
  border-radius: 50%;
  font-size: 11px;
  color: var(--fg-faint);
  transition: color .2s var(--t), background .2s var(--t);
}
.tab-action:hover { color: var(--accent); background: rgba(255, 255, 255, 0.04); }
.tab-action.danger:hover { color: var(--danger); }

.tab-add {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--fg-faint);
  padding: 14px 18px;
  text-transform: uppercase;
  border-left: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
  transition: color .2s var(--t), background .2s var(--t);
  flex-shrink: 0;
}
.tab-add:hover { color: var(--accent-soft); background: rgba(255, 255, 255, 0.02); }

.journal-input {
  width: 100%;
  min-height: 320px;
  resize: vertical;
  border: 0;
  outline: none;
  background: transparent;
  color: var(--fg);
  font-size: 1.02rem;
  line-height: 1.7;
  letter-spacing: 0.005em;
  padding: 26px 28px;
  font-family: var(--font-sans);
  caret-color: var(--accent);
  display: block;
}
.journal-input::placeholder { color: var(--fg-faint); font-style: italic; }

.journal-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 18px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--fg-faint);
  background: rgba(0, 0, 0, 0.25);
  flex-wrap: wrap;
  gap: 10px;
}
.journal-footer-left, .journal-footer-right { display: inline-flex; align-items: center; gap: 10px; }
.journal-meta { color: var(--fg-dim); }
.saved-indicator { color: var(--green-dim); transition: color .25s var(--t); }
.saved-indicator.is-saving { color: var(--accent-soft); }

/* =========================================================================
   Science CTA card
   ========================================================================= */
.cta-section { padding: clamp(40px, 8vh, 90px) 0; }
.cta-card {
  padding: clamp(24px, 4vw, 40px);
  display: grid;
  grid-template-columns: 1fr auto;
  gap: clamp(20px, 4vw, 40px);
  align-items: center;
}
.cta-text { display: grid; gap: 10px; max-width: 60ch; }
.cta-text h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.4rem, 2.6vw, 1.9rem);
  letter-spacing: -0.02em;
  color: #fff;
  line-height: 1.15;
}
.cta-text p { margin: 0; color: var(--fg-dim); font-size: 0.98rem; }

.cta-arrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 16px 24px;
  border-radius: 999px;
  border: 1px solid var(--accent);
  background: var(--accent-glow-2);
  color: var(--accent-soft);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  text-decoration: none;
  transition: transform .25s var(--t), background .25s var(--t), box-shadow .25s var(--t);
}
.cta-arrow:hover {
  transform: translateY(-2px);
  background: var(--accent-glow);
  box-shadow: 0 16px 40px -20px var(--accent-glow);
}
.cta-arrow-mark { font-size: 1.2em; }

/* =========================================================================
   Footer
   ========================================================================= */
.foot {
  margin-top: 30px;
  padding: 40px 0 60px;
  border-top: 1px solid var(--line);
  display: grid;
  gap: 18px;
}
.foot-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 20px;
}
.foot-block { display: grid; gap: 4px; }
.foot-key {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.24em;
  color: var(--fg-faint);
  text-transform: uppercase;
}
.foot-link {
  color: var(--fg);
  text-decoration: none;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.22);
  align-self: start;
  transition: color .2s var(--t), border-color .2s var(--t);
}
.foot-link:hover { color: var(--accent-soft); border-color: var(--accent); }
.foot-sub { font-size: 0.78rem; color: var(--fg-dim); margin-top: 4px; }
.foot-sub a {
  color: var(--fg-dim);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
  padding-bottom: 1px;
  transition: color .2s var(--t), border-color .2s var(--t);
}
.foot-sub a:hover { color: var(--accent); border-color: var(--accent); }
.foot-val { color: var(--fg-dim); font-family: var(--font-mono); font-size: 12px; }
.disclaimer { color: var(--fg-faint); font-size: 0.78rem; max-width: 80ch; margin: 6px 0 0; }

/* =========================================================================
   Learn page
   ========================================================================= */
.learn { display: grid; gap: 28px; max-width: 780px; margin: 0 auto; padding: 80px 0; }
.learn-back {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--fg-dim);
  text-decoration: none;
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: color .2s var(--t);
}
.learn-back:hover { color: var(--accent-soft); }

.learn-hero { display: grid; gap: 14px; margin-bottom: 8px; }
.learn-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  color: var(--accent);
  text-transform: uppercase;
}
.learn-hero h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2rem, 4.4vw, 3rem);
  letter-spacing: -0.025em;
  line-height: 1.1;
}
.learn-hero .lede { margin: 0; color: var(--fg-dim); font-size: 1.05rem; max-width: 60ch; }

.learn-section {
  padding: 24px 26px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.015);
}
.learn-section h2 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: -0.01em;
}
.learn-section h3 { margin: 18px 0 6px; font-size: 0.95rem; letter-spacing: 0.04em; color: var(--fg); font-weight: 600; }
.learn-section p { color: var(--fg-dim); margin: 0 0 10px; }
.learn-section p:last-child { margin-bottom: 0; }
.learn-section ul { margin: 4px 0 0; padding-left: 18px; color: var(--fg-dim); }
.learn-section ul li { margin-bottom: 6px; }
.learn-section strong { color: var(--fg); font-weight: 600; }
.learn-section em { color: var(--accent-soft); font-style: normal; }

.wave-table { width: 100%; border-collapse: collapse; margin-top: 6px; font-family: var(--font-mono); font-size: 12.5px; }
.wave-table th, .wave-table td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--line); color: var(--fg-dim); }
.wave-table th { color: var(--fg-faint); font-weight: 500; letter-spacing: 0.14em; text-transform: uppercase; font-size: 10.5px; }
.wave-table tr:last-child td { border-bottom: 0; }
.wave-table .row-theta td { color: var(--accent-soft); }
.wave-table b { color: var(--fg); font-weight: 600; }

.learn-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 8px; }
.learn-cta a {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 20px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 12px; letter-spacing: 0.2em; text-transform: uppercase;
  text-decoration: none; color: var(--fg);
  transition: color .2s var(--t), border-color .2s var(--t), background .2s var(--t);
}
.learn-cta a:hover { color: var(--accent-soft); border-color: var(--accent); background: var(--accent-glow-2); }
.learn-cta a.primary {
  border-color: var(--accent);
  color: var(--accent-soft);
  background: var(--accent-glow-2);
}
.learn-cta a.primary:hover { background: var(--accent-glow); }

/* =========================================================================
   Responsive
   ========================================================================= */
@media (max-width: 960px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 50px;
  }
  /* Centered title block on mobile/tablet */
  .hero-text {
    text-align: center;
    justify-items: center;
  }
  .title { justify-self: center; }
  .title-line { text-align: center; }
  .typing { text-align: center; justify-self: stretch; width: 100%; }
  /* Force the flex containers to span the full hero-text width so their
     justify-content: center actually centers the wrapped items rather than
     shrinking to max-content and overflowing the viewport. */
  .hero-meta, .brand-nav {
    justify-self: stretch;
    width: 100%;
    justify-content: center;
  }

  .hero-stage { justify-items: center; }
  .visualizer.is-hero { width: clamp(260px, 70vw, 380px); }
  .title { font-size: clamp(3.4rem, 16vw, 6rem); }
  .scroll-hint {
    position: static;
    margin-top: 30px;
    justify-self: center;
    display: inline-flex;
  }
  .tuning-head { justify-content: center; text-align: center; }
  .tuning-head > div { text-align: center; }
}

@media (max-width: 720px) {
  .hud { font-size: 10px; top: 12px; left: 12px; gap: 4px; }
  .hud-right { right: 12px; }
  .hud-right .hud-row:nth-child(n+3) { display: none; }

  .stage { padding: 0 16px; }
  .section { padding: 60px 0; }
  .hero { padding: 90px 0 60px; min-height: auto; }

  .title { letter-spacing: -0.045em; line-height: 0.9; }
  .hero-meta { gap: 8px; }

  .cta-card { grid-template-columns: 1fr; }
  .cta-arrow { justify-self: start; }

  .journal-input { min-height: 240px; padding: 18px; font-size: 1rem; }
  .journal-footer { padding: 10px 14px; }

  .preset-grid { grid-template-columns: 1fr 1fr; gap: 10px; }
  .preset { padding: 14px; }
  .preset-name { font-size: 0.98rem; }
  .preset-desc { font-size: 0.82rem; }

  .theme-grid { grid-template-columns: 1fr 1fr; }

  .glass::before {
    background-size: 26px 1px, 26px 1px, 26px 1px, 26px 1px, 1px 26px, 1px 26px, 1px 26px, 1px 26px;
  }
}

@media (max-width: 420px) {
  .preset-grid { grid-template-columns: 1fr; }
  .theme-grid { grid-template-columns: 1fr; }
  .foot-row { grid-template-columns: 1fr 1fr; }
  .hero-transport { gap: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .bg-grid, .bg-glow, .title-dot, .ring, .core, .typing-caret, .scroll-arrow { animation: none !important; }
}

/* =========================================================================
   Mobile / touch performance pass
   - backdrop-filter is the single most expensive effect on mobile GPUs and
     causes random repaints during scroll. Replace with a flat dark surface.
   - The two infinite background animations (grid drift, glow pulse) trigger
     continuous compositor work even when the page is idle. Stop them.
   - Smaller, cheaper reveal transitions on touch devices.
   ========================================================================= */
@media (hover: none) and (pointer: coarse), (max-width: 720px) {
  .glass {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    background: rgba(10, 10, 10, 0.86);
  }

  .bg-grid { animation: none; }
  .bg-glow { animation: none; opacity: 0.7; }
  .bg-scanline { display: none; }

  .reveal {
    opacity: 0.15;
    transform: translateY(14px);
    transition: opacity .55s var(--t), transform .55s var(--t);
  }

  /* Long-running shadow + blur on the bg-glow is fine when its animation is
     paused, but we keep the blur small to reduce paint cost. */
  .bg-glow { filter: blur(20px); }

  /* Paint/layout containment isolates each section's repaints, so a state
     change in one (e.g. journal typing, slider drag) doesn't invalidate the
     entire page. */
  .section, .hero, .foot { contain: layout paint style; }
  .journal-shell, .tuning-panel, .cta-card { contain: layout paint style; }
}

/* GPU layer hints for elements that animate continuously while playing — */
.ring, .core, .typing-caret, .bg-glow {
  transform: translateZ(0);
}