:root {
  --bg:      #080f1a;
  --card:    #0f1e30;
  --card2:   #132337;
  --surface: #172840;
  --accent:  #38bdf8;
  --accent2: #0ea5e9;
  --R:       #f87171;
  --L:       #60a5fa;
  --text:    #e1eaf4;
  --muted:   #6080a0;
  --border:  rgba(148,163,184,0.12);
  --border2: rgba(148,163,184,0.22);
  --active-beat-bg: rgba(56,189,248,0.18);
  --active-beat-border: rgba(56,189,248,0.7);
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: 'Inter', sans-serif;
  background: var(--bg);
  background-image:
    radial-gradient(ellipse 90% 40% at 50% -5%, rgba(14,165,233,0.11) 0%, transparent 65%),
    radial-gradient(ellipse 40% 30% at 90% 90%, rgba(56,189,248,0.04) 0%, transparent 55%);
  color: var(--text);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}
/* ── Nav ── */
nav {
  display: flex; align-items: center; gap: 0.55rem;
  padding: 0.85rem 1.75rem;
  background: rgba(8,15,26,0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 20;
}
nav a { color: var(--muted); text-decoration: none; font-size: 0.78rem; display: flex; align-items: center; gap: 0.3rem; transition: color 0.15s; }
nav a:hover { color: var(--text); }
nav .sep   { color: rgba(148,163,184,0.2); font-size: 0.7rem; }
nav .title { color: var(--text); font-weight: 600; font-size: 0.86rem; letter-spacing: -0.015em; }
/* ── Layout ── */
.app { max-width: 860px; margin: 0 auto; padding: 2rem 1.5rem 6rem; }
/* ── Page title ── */
.page-title {
  margin-bottom: 0.3rem;
  font-size: 1.6rem;
  font-weight: 800;
  letter-spacing: -0.03em;
}
.page-subtitle {
  font-size: 0.78rem;
  color: var(--muted);
  margin-bottom: 2rem;
  line-height: 1.6;
}
/* ── Section tabs ── */
.section-tabs {
  display: flex;
  background: var(--card2);
  border: 1px solid var(--border);
  border-radius: 0.65rem;
  padding: 3px;
  margin-bottom: 1.25rem;
  gap: 2px;
  width: fit-content;
  overflow-x: auto;
  scrollbar-width: none;
}
.section-tabs::-webkit-scrollbar { display: none; }
.section-tab {
  padding: 0.35rem 1rem;
  border-radius: 0.45rem;
  border: none;
  background: transparent;
  color: var(--muted);
  font-family: inherit;
  font-size: 0.75rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.18s;
  white-space: nowrap;
}
.section-tab.active {
  background: var(--surface);
  color: var(--text);
  font-weight: 600;
  box-shadow: 0 1px 4px rgba(0,0,0,0.35);
}
.section-tab:hover:not(.active) { color: var(--text); background: rgba(255,255,255,0.04); }
/* ── Pattern chips ── */
.pattern-chips { display: flex; gap: 0.3rem; flex-wrap: wrap; margin-bottom: 1.5rem; }
.pattern-chip {
  padding: 0.28rem 0.65rem;
  border-radius: 0.45rem;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  font-family: inherit;
  font-size: 0.73rem;
  font-weight: 400;
  cursor: pointer;
  transition: all 0.14s;
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: 0.3rem;
}
.pattern-chip.active {
  background: rgba(56,189,248,0.12);
  color: var(--accent);
  border-color: rgba(56,189,248,0.35);
  font-weight: 600;
}
.pattern-chip:hover:not(.active) { color: var(--text); border-color: var(--border2); background: var(--card2); }
.chip-dot { width: 5px; height: 5px; border-radius: 50%; background: currentColor; flex-shrink: 0; opacity: 0.6; }
.chip-done { color: #4ade80; opacity: 0.8; font-size: 0.6rem; }
/* ── Main practice card ── */
.practice-card {
  background: var(--card);
  border: 1px solid var(--border2);
  border-radius: 1.1rem;
  overflow: hidden;
  box-shadow: 0 4px 32px rgba(0,0,0,0.3), 0 1px 0 rgba(255,255,255,0.04) inset;
}
.card-inner { padding: 1.75rem 1.75rem 1.5rem; }
/* ── Pattern header ── */
.pattern-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1.4rem; }
.pattern-ex {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 0.3rem;
  opacity: 0.85;
}
.pattern-name-row { display: flex; align-items: center; gap: 0.8rem; }
.pattern-name { font-size: 1.4rem; font-weight: 700; letter-spacing: -0.02em; line-height: 1.2; }
.done-btn {
  margin-left: auto;
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 1.1rem;
  color: var(--muted);
  transition: color 0.14s, transform 0.14s;
  flex-shrink: 0;
  padding: 0.1rem 0.2rem;
}
.done-btn:hover { color: var(--text); transform: scale(1.2); }
.done-btn.active { color: #4ade80; }
/* ── Sticking beat display ── */
.exercises-stack {
  position: relative;
  margin-bottom: 1.75rem;
  display: flex;
  flex-direction: column;
  background: #f8fafc;
  border: 1px solid rgba(0,0,0,0.08);
  border-radius: 8px;
  overflow: hidden;
}
#beatDisplayNext {
  opacity: 0.38;
  border-top: 1px solid rgba(0,0,0,0.07);
}
.beat-wrap {
  position: relative;
  overflow: hidden;
}
/* Smooth playhead bar */
.playhead {
  position: absolute;
  top: 2px;
  bottom: 2px;
  left: 0%;
  width: 2px;
  background: rgba(30, 41, 59, 0.5);
  border-radius: 2px;
  transform: translateX(-50%);
  opacity: 0;
  pointer-events: none;
  will-change: left;
  box-shadow: 0 0 5px rgba(30,41,59,0.2);
  z-index: 2;
}
/* SVG scales to fill its container on any screen size */
.beat-svg {
  display: block;
  width: 100%;
  height: auto;
  overflow: visible;
}
.beat-cell {
  cursor: default;
  user-select: none;
}
/* ── Controls ── */
.controls {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}
/* BPM / Mode trigger + dropdown */
.right-controls { margin-left: auto; display: flex; align-items: center; gap: 0.5rem; }
.bpm-trigger-wrap { position: relative; }
.bpm-trigger {
  display: flex;
  align-items: baseline;
  gap: 0.3rem;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border2);
  border-radius: 8px;
  padding: 0.35rem 0.65rem;
  cursor: pointer;
  color: var(--text);
  font-family: inherit;
  transition: background 0.12s, border-color 0.12s;
}
.bpm-trigger:hover { background: rgba(255,255,255,0.09); border-color: rgba(56,189,248,0.35); }
#bpmDisplay, #modeDisplay { font-size: 1.6rem; font-weight: 800; letter-spacing: -0.04em; line-height: 1; }
.bpm-unit { font-size: 0.7rem; color: var(--muted); font-weight: 500; }
.bpm-dropdown {
  display: none;
  position: absolute;
  bottom: calc(100% + 8px);
  right: 0;
  background: var(--card);
  border: 1px solid var(--border2);
  border-radius: 12px;
  padding: 1rem;
  min-width: 210px;
  box-shadow: 0 8px 28px rgba(0,0,0,0.45);
  z-index: 100;
}
.bpm-dropdown.open { display: block; }
#modeDropdown { left: 0; right: auto; min-width: 170px; }
.mode-opt {
  display: block;
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  border-radius: 6px;
  padding: 0.4rem 0.55rem;
  color: var(--text);
  font-family: inherit;
  font-size: 0.82rem;
  cursor: pointer;
  transition: background 0.12s;
  opacity: 0.8;
}
.mode-opt:hover { background: rgba(255,255,255,0.07); opacity: 1; }
.mode-opt.active { color: var(--accent); font-weight: 600; opacity: 1; }
#modeTrigger.mode-active { border-color: rgba(56,189,248,0.4); color: var(--accent); }
input[type=range] {
  -webkit-appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  background: rgba(255,255,255,0.07);
  cursor: pointer;
  outline: none;
}
input[type=range]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 8px rgba(56,189,248,0.4);
  cursor: pointer;
  transition: transform 0.1s;
}
input[type=range]::-webkit-slider-thumb:hover { transform: scale(1.2); }
input[type=range]::-moz-range-thumb {
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  cursor: pointer;
}
.tempo-presets { display: flex; gap: 0.3rem; }
.tempo-btn {
  padding: 0.22rem 0.6rem;
  border-radius: 2rem;
  border: 1px solid var(--border2);
  background: transparent;
  color: var(--muted);
  font-family: inherit;
  font-size: 0.68rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.13s;
  white-space: nowrap;
}
.tempo-btn:hover { color: var(--text); background: rgba(255,255,255,0.06); }
.tempo-btn.active { color: var(--accent); border-color: rgba(56,189,248,0.4); background: rgba(56,189,248,0.09); font-weight: 600; }
/* Play row */
.play-row {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.play-btn {
  width: 48px; height: 48px;
  border-radius: 50%;
  border: none;
  background: var(--accent);
  color: #061422;
  font-size: 1.15rem;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  transition: background 0.15s, transform 0.1s;
  box-shadow: 0 0 20px rgba(56,189,248,0.3);
}
.play-btn:hover { background: #7dd3fc; transform: scale(1.06); }
.play-btn.playing { background: var(--R); color: #fff; box-shadow: 0 0 20px rgba(248,113,113,0.35); }
.play-btn.playing:hover { background: #fca5a5; }
.metronome-info { display: flex; flex-direction: column; gap: 0.2rem; }
.loop-counter { font-size: 0.72rem; color: var(--muted); font-variant-numeric: tabular-nums; }
.loop-count { color: var(--accent); font-weight: 600; }
.beat-counter { font-size: 0.68rem; color: var(--muted); font-variant-numeric: tabular-nums; }
/* Accent toggle */
.options-row {
  display: flex;
  gap: 0.7rem;
  flex-wrap: wrap;
  align-items: center;
}
.option-label { font-size: 0.68rem; color: var(--muted); font-weight: 500; }
.toggle-btn {
  padding: 0.22rem 0.65rem;
  border-radius: 2rem;
  border: 1px solid var(--border2);
  background: transparent;
  color: var(--muted);
  font-family: inherit;
  font-size: 0.7rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.13s;
}
.toggle-btn.on { color: var(--accent); border-color: rgba(56,189,248,0.4); background: rgba(56,189,248,0.09); font-weight: 600; }
.toggle-btn:hover { color: var(--text); }
/* ── Card nav arrows ── */
.card-nav {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}
.card-nav .practice-card { flex: 1; min-width: 0; }
.nav-arrow {
  flex-shrink: 0;
  width: 38px; height: 38px;
  border-radius: 50%;
  border: 1px solid var(--border2);
  background: var(--card);
  color: var(--muted);
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: color 0.15s, border-color 0.15s, background 0.15s;
  box-shadow: 0 2px 8px rgba(0,0,0,0.25);
}
.nav-arrow:hover:not(:disabled) { color: var(--text); border-color: rgba(56,189,248,0.4); background: var(--card2); }
.nav-arrow:disabled { opacity: 0.15; cursor: default; }
/* ── Animations ── */
@keyframes card-in  { from { opacity:0; transform:translateX(28px) scale(0.985); } to { opacity:1; transform:translateX(0) scale(1); } }
@keyframes card-in-r{ from { opacity:0; transform:translateX(-28px) scale(0.985); } to { opacity:1; transform:translateX(0) scale(1); } }
.practice-card.anim-in   { animation: card-in   0.26s cubic-bezier(0,0,0.2,1) forwards; }
.practice-card.anim-in-r { animation: card-in-r 0.26s cubic-bezier(0,0,0.2,1) forwards; }
/* ── Legend ── */
.legend {
  display: flex; gap: 1.1rem; font-size: 0.68rem; color: var(--muted);
  flex-wrap: wrap; padding: 1rem 1.75rem;
  border-top: 1px solid var(--border);
  opacity: 0.7;
}
.legend span { display: flex; align-items: center; gap: 0.28rem; }
.ldot { width: 8px; height: 8px; border-radius: 50%; }
/* ── Progress summary ── */
.progress-bar-row {
  display: flex; gap: 3px; height: 4px; border-radius: 3px; overflow: hidden;
  margin-bottom: 1.5rem;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent2), var(--accent));
  border-radius: 3px;
  transition: width 0.5s cubic-bezier(0.4,0,0.2,1);
  box-shadow: 0 0 8px rgba(56,189,248,0.3);
}
.progress-track { flex: 1; background: rgba(255,255,255,0.06); border-radius: 3px; }
.progress-label { font-size: 0.7rem; color: var(--muted); margin-bottom: 0.5rem; }
.done-count { color: var(--accent); font-weight: 600; }
/* ── Keyboard hint ── */
.kbd-hint { font-size: 0.65rem; color: var(--muted); opacity: 0.6; margin-top: 0.3rem; }
kbd { display: inline-block; padding: 0.05rem 0.3rem; border: 1px solid var(--border2); border-radius: 0.25rem; font-size: 0.62rem; font-family: inherit; }

/* ── Page transitions ── */
@keyframes pageEnter {
  from { opacity: 0; transform: scale(0.97) translateY(8px); filter: blur(3px); }
  to   { opacity: 1; transform: scale(1)    translateY(0);   filter: blur(0);   }
}
@keyframes pageExit {
  from { opacity: 1; transform: scale(1);    filter: blur(0);   }
  to   { opacity: 0; transform: scale(0.98); filter: blur(3px); }
}
/* Start invisible; JS adds .page-loaded after first paint to trigger enter */
body {
  opacity: 0;
}
body.page-loaded {
  animation: pageEnter 0.45s cubic-bezier(0.22, 1, 0.36, 1) both;
}
body.page-exit {
  animation: pageExit 0.32s ease-out both;
  pointer-events: none;
}