:root {
  /* Palette — warm, playful, low-saturation paper feel */
  --color-bg: #f4ead5;
  --color-bg-2: #efe2b9;
  --color-ink: #1a1612;
  --color-ink-soft: #5a4a39;
  --color-mute: #8a7862;
  --color-line: rgba(26, 22, 18, 0.12);
  --color-surface: #fffaf0;
  --color-surface-dim: rgba(255, 250, 240, 0.85);

  --color-dino: #6fba63;
  --color-dino-dark: #3d7a3a;
  --color-neck: #ff8ab6;
  --color-neck-dark: #d65a8c;
  --color-accent: #f0a13a;
  --color-danger: #d64545;

  --font-display: 'Cabinet Grotesk', ui-sans-serif, system-ui, sans-serif;
  --font-body: 'Satoshi', ui-sans-serif, system-ui, sans-serif;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;

  --shadow-sm: 0 1px 2px rgba(26, 22, 18, 0.08), 0 2px 8px rgba(26, 22, 18, 0.06);
  --shadow-md: 0 2px 6px rgba(26, 22, 18, 0.1), 0 16px 40px rgba(26, 22, 18, 0.12);

  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

* {
  box-sizing: border-box;
}
html,
body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: var(--color-bg);
  color: var(--color-ink);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

#app {
  position: fixed;
  inset: 0;
  overflow: hidden;
}

#game {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  background:
    radial-gradient(
      circle at 20% 0%,
      rgba(255, 255, 255, 0.45),
      transparent 55%
    ),
    linear-gradient(180deg, var(--color-bg-2) 0%, var(--color-bg) 100%);
}

/* ---------- Screens ---------- */

.screen {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 320ms var(--ease);
  z-index: 20;
}
.screen.active {
  opacity: 1;
  pointer-events: auto;
}
.screen-inner {
  width: min(540px, 100%);
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  box-shadow: var(--shadow-md);
  text-align: center;
}
.logo {
  color: var(--color-ink);
  display: inline-flex;
  margin-bottom: 6px;
}
h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2rem, 5vw, 2.75rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin: 4px 0 8px;
}
h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.6rem, 4vw, 2.1rem);
  margin: 0 0 6px;
  letter-spacing: -0.015em;
}
.tag {
  color: var(--color-ink-soft);
  margin: 0 0 20px;
  font-size: 15px;
}
.tag b {
  color: var(--color-ink);
}

.rules {
  text-align: left;
  display: grid;
  gap: 10px;
  padding: 16px 18px;
  background: var(--color-bg);
  border-radius: var(--radius-md);
  margin-bottom: 20px;
}
.rule {
  font-size: 14.5px;
  color: var(--color-ink);
}
.rule b {
  color: var(--color-dino-dark);
  margin-right: 8px;
  font-family: var(--font-display);
  font-weight: 700;
}

/* Buttons */
.btn-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 4px;
}
.btn {
  appearance: none;
  border: 0;
  font: inherit;
  font-weight: 600;
  font-size: 15px;
  padding: 12px 20px;
  border-radius: 999px;
  cursor: pointer;
  transition:
    transform 180ms var(--ease),
    background 180ms var(--ease),
    box-shadow 180ms var(--ease);
}
.btn.primary {
  background: var(--color-ink);
  color: var(--color-surface);
  box-shadow: var(--shadow-sm);
}
.btn.primary:hover {
  transform: translateY(-1px);
}
.btn.primary:disabled {
  background: var(--color-mute);
  cursor: not-allowed;
  transform: none;
}
.btn.ghost {
  background: transparent;
  color: var(--color-ink);
  border: 1px solid var(--color-line);
}
.btn.ghost:hover {
  background: var(--color-bg);
}
.fine {
  margin: 14px 0 0;
  color: var(--color-mute);
  font-size: 12.5px;
}

/* ---------- Calibration ---------- */

.cal-reading {
  background: var(--color-bg);
  border-radius: var(--radius-md);
  padding: 18px;
  margin: 8px 0 16px;
}
.cal-freq {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 48px;
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}
.cal-unit {
  font-size: 16px;
  color: var(--color-mute);
  margin-left: 6px;
  font-weight: 500;
}
.cal-note {
  margin-top: 4px;
  color: var(--color-ink-soft);
  font-size: 14px;
}
.cal-bar {
  margin: 14px auto 8px;
  height: 8px;
  width: 80%;
  background: var(--color-line);
  border-radius: 999px;
  overflow: hidden;
}
.cal-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--color-dino), var(--color-accent));
  transition: width 120ms linear;
}
.cal-status {
  font-size: 13px;
  color: var(--color-mute);
  min-height: 1.2em;
}
.cal-captured {
  display: flex;
  gap: 18px;
  justify-content: center;
  margin-bottom: 16px;
  font-family: var(--font-display);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}
.cal-captured > div {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

/* ---------- HUD ---------- */

#hud {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  padding: 18px 22px;
  z-index: 10;
  pointer-events: none;
  font-family: var(--font-body);
}
.hidden {
  display: none !important;
}
.hud-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-mute);
  text-transform: uppercase;
}
.hud-value {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 34px;
  line-height: 1;
  font-variant-numeric: tabular-nums lining-nums;
  letter-spacing: -0.02em;
}
.hud-value.big {
  font-size: 44px;
}
.hud-sub {
  font-size: 12px;
  color: var(--color-ink-soft);
  margin-top: 4px;
  font-variant-numeric: tabular-nums;
}
.hud-right {
  text-align: right;
}
.hud-hearts {
  font-size: 24px;
  color: var(--color-danger);
  letter-spacing: 2px;
  line-height: 1;
  margin-top: 4px;
}

/* ---------- Pitch meter ---------- */

#pitchMeter {
  position: absolute;
  left: 50%;
  bottom: 20px;
  transform: translateX(-50%);
  width: min(440px, calc(100% - 32px));
  background: var(--color-surface-dim);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  z-index: 10;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
}
.pm-label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--font-display);
  font-weight: 700;
}
#pmNote {
  font-size: 18px;
  letter-spacing: -0.01em;
}
.pm-freq {
  font-size: 12px;
  color: var(--color-mute);
  font-variant-numeric: tabular-nums;
  font-family: var(--font-body);
  font-weight: 500;
}
.pm-track {
  position: relative;
  height: 10px;
  background: var(--color-line);
  border-radius: 999px;
  margin: 8px 0 6px;
  overflow: hidden;
}
.pm-lanes {
  position: absolute;
  inset: 0;
  display: flex;
}
.pm-lanes span {
  flex: 1;
  border-right: 1px dashed rgba(26, 22, 18, 0.18);
}
.pm-lanes span:last-child {
  border-right: 0;
}
.pm-bar {
  position: absolute;
  top: 0;
  left: 0%;
  width: 6px;
  height: 100%;
  background: var(--color-ink);
  border-radius: 3px;
  transition: left 90ms linear;
}
.pm-foot {
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  color: var(--color-mute);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

/* ---------- Gameover ---------- */

.gg-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  padding: 18px 0 24px;
}
.gg-stats > div {
  display: flex;
  flex-direction: column;
  gap: 6px;
  align-items: center;
}

/* ---------- Toast ---------- */

.toast {
  position: absolute;
  left: 50%;
  top: 18px;
  transform: translateX(-50%);
  background: var(--color-ink);
  color: var(--color-surface);
  padding: 10px 16px;
  border-radius: 999px;
  font-size: 13px;
  z-index: 40;
  box-shadow: var(--shadow-md);
}

/* ---------- Song picker ---------- */

.song-list {
  display: grid;
  gap: 8px;
  margin: 6px 0 18px;
  max-height: 44vh;
  overflow-y: auto;
  padding: 2px;
}
.song-item {
  appearance: none;
  font: inherit;
  text-align: left;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 16px;
  background: var(--color-bg);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  color: var(--color-ink);
  cursor: pointer;
  transition:
    transform 160ms var(--ease),
    background 160ms var(--ease),
    border-color 160ms var(--ease),
    box-shadow 160ms var(--ease);
}
.song-item:hover {
  background: var(--color-surface);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}
.song-item.selected {
  background: var(--color-surface);
  border-color: var(--color-dino-dark);
  box-shadow:
    0 0 0 2px rgba(61, 122, 58, 0.18),
    var(--shadow-sm);
}
.song-item-main {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}
.song-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--color-ink);
}
.song-sub {
  font-size: 12.5px;
  color: var(--color-ink-soft);
}
.song-meta {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 2px;
  font-variant-numeric: tabular-nums;
  flex-shrink: 0;
}
.song-notes {
  font-size: 12px;
  color: var(--color-ink);
  font-weight: 600;
}
.song-bpm {
  font-size: 11px;
  color: var(--color-mute);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ---------- Mobile ---------- */
@media (max-width: 520px) {
  .screen-inner {
    padding: 24px 20px;
  }
  .hud-value {
    font-size: 28px;
  }
  #hud {
    padding: 14px 16px;
  }
  .song-item {
    padding: 10px 14px;
  }
  .song-title {
    font-size: 15px;
  }
}