/* Core layout */
:root {
  color-scheme: light dark;
  --bg: #0b1021;
  --panel: rgba(255, 255, 255, 0.06);
  --card: rgba(255, 255, 255, 0.09);
  --text: #f8fafc;
  --muted: #cbd5e1;
  --accent: #38bdf8;
  --accent-strong: #14b8a6;
  --border: rgba(255, 255, 255, 0.15);
  --key-white: #fdfdfd;
  --key-black: #111827;
  --key-active: #fbbf24;
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-right: env(safe-area-inset-right, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
  --safe-left: env(safe-area-inset-left, 0px);
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: radial-gradient(circle at 20% 20%, #111827, #0b1021 40%),
              radial-gradient(circle at 80% 10%, #0f172a, #0b1021 45%),
              #0b1021;
  color: var(--text);
  font-family: "SF Pro Display", "Segoe UI", "Helvetica Neue", sans-serif;
  touch-action: manipulation;
  overscroll-behavior: none;
  -webkit-user-select: none;
  user-select: none;
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
}

.app-shell {
  position: relative;
  width: 100%;
  height: 100%;
  padding: calc(16px + var(--safe-top)) calc(16px + var(--safe-right)) calc(16px + var(--safe-bottom)) calc(16px + var(--safe-left));
}

.hidden { display: none !important; }

/* Portrait UI */
.screen.portrait {
  max-width: 520px;
  margin: 0 auto;
  display: grid;
  gap: 12px;
}

.header h1 {
  margin: 0;
  font-size: 28px;
  letter-spacing: 0.4px;
}

.subtitle {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 14px 16px;
  display: grid;
  gap: 10px;
}

.card label {
  font-size: 14px;
  color: var(--muted);
}

select, button, input[type="radio"], input[type="checkbox"] {
  font: inherit;
}

select {
  width: 100%;
  padding: 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
}

.mode-toggle {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 8px;
}

.chip {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.05);
}

.chip input { margin: 0; }

.settings {
  display: grid;
  gap: 8px;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
}

.actions {
  display: flex;
  gap: 10px;
  margin-top: 4px;
}

.notice {
  text-align: center;
  font-weight: 800;
  letter-spacing: 1px;
  padding: 12px;
  border: 1px dashed var(--border);
  border-radius: 12px;
  background: rgba(56, 189, 248, 0.08);
}

.desktop-only { display: inline-flex; }
@media (pointer: coarse) {
  .desktop-only { display: none !important; }
  #home-btn { display: none !important; }
}

button {
  cursor: pointer;
  border: none;
  border-radius: 12px;
  padding: 12px 16px;
  font-weight: 700;
  color: #0b1021;
  background: var(--accent);
  transition: transform 0.08s ease, box-shadow 0.12s ease;
  box-shadow: 0 10px 30px rgba(56, 189, 248, 0.25);
}

button:active { transform: translateY(1px); }

button.ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
  box-shadow: none;
}

button.primary { background: linear-gradient(120deg, var(--accent), var(--accent-strong)); color: #0b1021; }

.footnote {
  color: var(--muted);
  font-size: 12px;
  margin: 6px 0 0;
}

/* Landscape UI */
.screen.landscape {
  width: 100%;
  height: 100%;
  display: grid;
  grid-template-rows: auto 1fr;
  gap: 10px;
}

.top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 10px 14px;
}

.top-info {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
  margin: 0 12px;
  flex-wrap: wrap;
}

.status-text {
  font-weight: 700;
}

.info-text {
  font-size: 14px;
  color: var(--muted);
}

.info-scale { color: #fbbf24; }
.info-mode { color: #38bdf8; }
.info-level { color: #fca5a5; }

.keyboard-wrapper {
  position: relative;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.06), rgba(255, 255, 255, 0.02));
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06);
  height: calc(100% - 8px);
  padding: 12px;
}

.inline-error {
  position: absolute;
  top: 74%;
  left: 50%;
  transform: translate(-50%, -50%);
  padding: 14px 18px;
  border-radius: 10px;
  background: rgba(239, 68, 68, 0.18);
  color: #ffe4e6;
  border: 1px solid rgba(248, 113, 113, 0.5);
  font-weight: 900;
  font-size: 16px;
  letter-spacing: 0.2px;
  text-shadow:
    -1px -1px 0 #7f1d1d,
     1px -1px 0 #7f1d1d,
    -1px  1px 0 #7f1d1d,
     1px  1px 0 #7f1d1d;
  z-index: 3;
}

.keyboard {
  position: relative;
  width: 100%;
  height: 100%;
  -webkit-user-select: none;
  user-select: none;
  touch-action: manipulation;
}

.key {
  position: relative;
  overflow: hidden;
}

/* Assist toggle: only hide key labels when assist is turned off */
.assist-hidden .note-label,
.assist-hidden .key-label {
  display: none !important;
}

.white-keys {
  display: flex;
  height: 100%;
}

.white-key {
  flex: 0 0 auto;
  margin: 0;
  background: var(--key-white);
  border: 1px solid #d1d5db;
  border-radius: 0 0 8px 8px;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.25);
  position: relative;
  z-index: 1;
}

.white-key.placeholder {
  background: var(--key-white);
  border: 1px solid #d1d5db;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.2);
}

.black-keys {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 62%;
  pointer-events: auto;
}

.black-key {
  position: absolute;
  background: linear-gradient(180deg, #111827, #0b1021);
  border: 1px solid #0f172a;
  border-radius: 0 0 8px 8px;
  box-shadow: 0 10px 18px rgba(0, 0, 0, 0.45);
  height: 100%;
  z-index: 2;
  pointer-events: auto;
}

.key-label {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 12px;
  color: #475569;
  font-weight: 700;
  pointer-events: none;
}

.white-key .key-label { color: #1e293b; }
.black-key .key-label { color: #e2e8f0; }

.key::after {
  content: "";
  position: absolute;
  inset: 0;
  background: transparent;
  opacity: 0;
  pointer-events: none;
  transition: opacity 120ms ease;
}

.key.active-sequence::after {
  background: rgba(125, 211, 252, 0.55);
  opacity: 1;
}

.key.active-user::after {
  background: rgba(248, 113, 113, 0.55);
  opacity: 1;
}

.orientation-message {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(0, 0, 0, 0.6);
  text-align: center;
  font-weight: 700;
  z-index: 10;
}

/* Responsive tweaks */
@media (max-width: 600px) {
  .screen.landscape { grid-template-rows: auto auto 1fr; }
  .keyboard-wrapper { padding: 10px; }
  .key-label { display: none; }
}