:root {
  --bg: #0b0b0d;
  --card-bg: #131316;
  --border-dim: #2a2a30;
  --lane-line: #45454e;
  --lane-line-mid: rgba(255, 255, 255, 0.22);
  --text-dim: #7a7a84;
  --text: #e8e8ec;
  --accent: #2ee6a5;
  --danger: #ff4d5e;
  --font: "Segoe UI", Arial, Helvetica, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
  margin: 0;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 24px;
}

#app {
  width: 820px;
  max-width: 100%;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

/* ---------- config panel ---------- */
#config-panel {
  background: var(--card-bg);
  border: 1px solid var(--border-dim);
  border-radius: 8px;
  padding: 16px 20px;
  display: grid;
  grid-template-columns: 31% 31% 31%;
  gap: 20px 28px;
}

.config-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.config-item label {
  font-size: 11px;
  letter-spacing: 1.5px;
  color: var(--text-dim);
}

.config-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.config-row input[type="range"] {
  flex: 1;
  min-width: 0;
  accent-color: var(--accent);
  cursor: pointer;
}

.config-row input[type="range"]:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.config-value {
  font-size: 12px;
  font-weight: 700;
  color: var(--text);
  min-width: 32px;
  flex-shrink: 0;
  text-align: right;
  white-space: nowrap;
}

/* ---------- game card ---------- */
#game-card {
  background: var(--card-bg);
  border: 1px solid var(--border-dim);
  border-radius: 8px;
  padding: 16px;
}

#tracks-wrapper {
  position: relative;
}

#tracks {
  display: flex;
  flex-direction: column;
}

.track-row {
  position: relative;
  height: 96px;
  border-top: 1px solid var(--lane-line);
  border-bottom: 1px solid var(--lane-line);
  margin-top: -1px;
  overflow: hidden;
  transition: box-shadow 0.12s ease, border-color 0.12s ease;
}

.track-row .lane-label {
  position: absolute;
  top: 8px;
  left: 14px;
  font-size: 11px;
  letter-spacing: 1.5px;
  color: var(--text-dim);
  z-index: 2;
}

.track-row .center-line {
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 1px;
  background: var(--lane-line-mid);
}

.track-row .hit-zone {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 36px;
  left: calc(15% - 17.5px);
  display: flex;
  justify-content: space-between;
  align-items: stretch;
  z-index: 1;
  pointer-events: none;
  background: color-mix(in srgb, var(--row-color, var(--accent)) 5%, transparent);
}

.track-row .hz-line {
  width: 1px;
  background: var(--row-color, var(--accent));
  opacity: 0.85;
}

.track-row .hz-line.hz-mid {
  width: 3px;
}

.track-row .key-badge {
  position: absolute;
  top: 50%;
  right: 14px;
  transform: translateY(-50%);
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--row-color, var(--accent));
  border-radius: 4px;
  font-weight: 700;
  font-size: 13px;
  color: var(--text);
  background: var(--card-bg);
  z-index: 2;
}

.track-row.glow-good {
  box-shadow: inset 0 0 0 2px #4dff8a, 0 0 14px rgba(77, 255, 138, 0.5);
  border-color: #4dff8a;
}

.track-row.glow-bad {
  box-shadow: inset 0 0 0 2px var(--danger), 0 0 14px rgba(255, 77, 94, 0.5);
  border-color: var(--danger);
}

.diamond {
  position: absolute;
  top: 50%;
  width: 28px;
  height: 28px;
  border: 2px solid var(--row-color, var(--accent));
  background: var(--card-bg);
  transform: translate(-50%, -50%) rotate(45deg);
  transition: background 0.1s ease, opacity 0.2s ease;
  z-index: 1;
}

.diamond.hit {
  background: var(--row-color, var(--accent));
}

/* ---------- stat row ---------- */
#statrow {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
  padding-top: 14px;
  font-size: 12px;
  letter-spacing: 1px;
  color: var(--text-dim);
}

#statrow b {
  color: var(--text);
  font-weight: 700;
}

.progress-track {
  flex: 1;
  min-width: 140px;
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 3px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: var(--accent);
  transition: width 0.1s linear;
}

/* ---------- overlays ---------- */
.overlay {
  position: absolute;
  inset: 0;
  background: rgba(6, 6, 8, 0.6);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 14px;
  padding: 20px;
  z-index: 5;
}

.overlay.hidden { display: none; }

.overlay h2 {
  font-family: var(--font);
  font-weight: 900;
  font-style: italic;
  font-size: 30px;
  letter-spacing: 1px;
  margin: 0;
  color: var(--text);
}

.overlay h2.pass-text {
  color: #4dff8a;
  font-size: 46px;
  text-shadow: 0 0 24px rgba(77, 255, 138, 0.6);
}

.overlay h2.fail-text {
  color: var(--danger);
  font-size: 46px;
  text-shadow: 0 0 24px rgba(255, 77, 94, 0.6);
}

.overlay-sub {
  margin: 0;
  font-size: 13px;
  color: var(--text-dim);
  letter-spacing: 0.5px;
}

.key-hint {
  margin: 0;
  font-size: 14px;
  font-weight: bold;
  color: var(--text-dim);
  letter-spacing: 0.5px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.key {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  border: 1px solid var(--text);
  border-radius: 3px;
  font-size: 12px;
  font-weight: 700;
  color: black;
  background: var(--text);
}

@media (max-width: 640px) {
  .track-row { height: 76px; }
  .diamond { width: 22px; height: 22px; }
  #statrow { gap: 12px; }
}