/* ─── FretVision — Main CSS ─────────────────────────────────────────────── */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&display=swap');

:root {
  --color-bg:         #0f172a;   /* slate-900 */
  --color-surface:    #1e293b;   /* slate-800 */
  --color-border:     #334155;   /* slate-700 */
  --color-text:       #e2e8f0;   /* slate-200 */
  --color-muted:      #94a3b8;   /* slate-400 */
  --color-accent:     #06b6d4;   /* cyan-500  */
  --color-accent-dim: #0e7490;   /* cyan-700  */
  --font-sans:        'Inter', system-ui, sans-serif;
  --radius:           6px;
  --header-h:         60px;
  --footer-h:         52px;
}

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

html, body {
  height: 100%;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

#app {
  display: flex;
  flex-direction: column;
  height: 100%;
}

/* ── Header ────────────────────────────────────────────────────────────── */
.app-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 10px;
  flex-wrap: wrap;
}

.app-header .logo {
  font-weight: 700;
  font-size: 20px;
  color: var(--color-accent);
  letter-spacing: -0.5px;
  white-space: nowrap;
  margin-right: 4px;
}

/* ── Scale banner ───────────────────────────────────────────────────── */
.scale-banner {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: 12px 16px;
  text-align: center;
  flex-shrink: 0;
}

.scale-banner-label {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-accent);
  letter-spacing: -0.5px;
}

/* ── Main fretboard area ─────────────────────────────────────────────── */
.fretboard-area {
  flex: 1;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 16px 0 8px;
  display: flex;
  align-items: center;
  /* iOS momentum scroll */
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--color-border) transparent;
}

.fretboard-area::-webkit-scrollbar { height: 4px; }
.fretboard-area::-webkit-scrollbar-track { background: transparent; }
.fretboard-area::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 2px;
}

#fretboard-container {
  width: 100%;
  min-width: 700px;
  padding: 0 16px;
}

.fretboard-svg {
  width: 100%;
  height: auto;
  display: block;
}

/* ── Footer ────────────────────────────────────────────────────────────── */
.app-footer {
  position: sticky;
  bottom: 0;
  z-index: 50;
  height: var(--footer-h);
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 16px;
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-link {
  font-size: 12px;
  font-weight: 500;
  color: var(--color-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-link:hover {
  color: var(--color-accent);
}

.footer-dot {
  color: var(--color-border);
  font-size: 14px;
  user-select: none;
}

/* ── Scroll hint (desktop horizontal scroll) ─────────────────────────── */
.scroll-hint {
  display: none;
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  background: linear-gradient(to left, var(--color-bg) 40%, transparent);
  width: 48px;
  height: 100%;
  pointer-events: none;
}

/* ── Controls toggle (mobile only, hidden on desktop) ────────────────── */
.controls-toggle-btn { display: none; }
.header-scale-label  { display: none; }

/* ── Controls panel: inline on desktop ──────────────────────────────── */
#controls-panel {
  display: contents; /* children participate in header flex flow */
}

/* ── Mobile breakpoint ───────────────────────────────────────────────── */
@media (max-width: 599px) {

  /* Header: single tight row */
  .app-header {
    position: relative;
    height: var(--header-h);
    padding: 0 12px;
    gap: 8px;
    flex-wrap: nowrap;
    align-items: center;
  }

  /* Show mobile-only elements */
  .controls-toggle-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 6px 10px;
    font-size: 13px;
    font-weight: 500;
    font-family: var(--font-sans);
    color: var(--color-muted);
    cursor: pointer;
    min-height: 36px;
    white-space: nowrap;
    transition: border-color 0.2s, color 0.2s;
  }
  .controls-toggle-btn:hover,
  .controls-toggle-btn.active {
    border-color: var(--color-accent);
    color: var(--color-accent);
  }
  .controls-toggle-arrow { font-size: 10px; }

  .header-scale-label {
    display: block;
    flex: 1;
    text-align: right;
    font-size: 14px;
    font-weight: 700;
    color: var(--color-accent);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    min-width: 0;
  }

  /* Controls panel: hidden dropdown */
  #controls-panel {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: 12px;
    flex-wrap: wrap;
    gap: 10px;
    z-index: 48;
    align-items: center;
  }
  #controls-panel.open {
    display: flex;
  }

  /* Hide dividers inside panel on mobile */
  #controls-panel .ctrl-divider { display: none; }

  /* Hide desktop-only scale banner */
  .scale-banner { display: none; }

  /* Fretboard: vertical mode */
  #fretboard-container {
    min-width: unset;
    width: 100%;
    padding: 0 8px;
  }
  .fretboard-area {
    overflow-x: hidden;
    overflow-y: auto;
    align-items: flex-start;
    padding: 8px 0;
  }
  .fretboard-svg--vertical {
    width: 100%;
    height: auto;
    display: block;
  }
}

/* ── Very small screens ──────────────────────────────────────────────── */
@media (max-width: 380px) {
  .random-label { display: none; }
  .header-scale-label { font-size: 12px; }
}

/* ── Footer responsive ───────────────────────────────────────────────── */
@media (max-width: 480px) {
  .footer-links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
  }
  .footer-dot { display: none; }
}