/* ═══════════════════════════════════════════════════════════════
   LUMINA — Premium Scientific & Financial Calculator
   Matte black glass · Gold accents · OLED-ready
   ═══════════════════════════════════════════════════════════════ */

/* Default = Lumina Gold (dark) */
:root, [data-skin="lumina"] {
  --bg: #0a0a0b;
  --bg-elevated: #121214;
  --glass: rgba(22, 22, 26, 0.72);
  --glass-border: rgba(255, 255, 255, 0.06);
  --accent: #c9a227;
  --accent-dim: #9a7b1a;
  --accent-glow: rgba(201, 162, 39, 0.25);
  --text: #f2f0ea;
  --text-muted: #8a8780;
  --text-dim: #5c5a55;
  --key: #1c1c20;
  --key-hover: #26262c;
  --key-active: #2e2e36;
  --op: #2a2418;
  --op-hover: #3a3220;
  --equals: linear-gradient(135deg, #c9a227 0%, #a8841a 100%);
  --equals-text: #0a0a0b;
  --danger: #c44;
  --success: #4a9;
  --radius: 14px;
  --radius-sm: 10px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.45);
  --font: "Inter", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;
  --safe-bottom: env(safe-area-inset-bottom, 0px);
}

/* Alias legacy gold vars */
:root, [data-skin] {
  --gold: var(--accent);
  --gold-dim: var(--accent-dim);
  --gold-glow: var(--accent-glow);
}

/* ── Design skins ── */
[data-skin="obsidian"] {
  --bg: #050508;
  --bg-elevated: #0c0c10;
  --glass: rgba(12, 12, 18, 0.8);
  --glass-border: rgba(255, 255, 255, 0.05);
  --accent: #e8e8ec;
  --accent-dim: #a0a0a8;
  --accent-glow: rgba(232, 232, 236, 0.15);
  --text: #f5f5f7;
  --text-muted: #8e8e96;
  --text-dim: #55555c;
  --key: #141418;
  --key-hover: #1c1c22;
  --key-active: #24242c;
  --op: #1a1a20;
  --op-hover: #282830;
  --equals: linear-gradient(135deg, #e8e8ec 0%, #b8b8c0 100%);
  --equals-text: #0a0a0c;
}

[data-skin="ocean"] {
  --bg: #061018;
  --bg-elevated: #0a1824;
  --glass: rgba(10, 28, 42, 0.75);
  --glass-border: rgba(80, 180, 255, 0.1);
  --accent: #3dbbff;
  --accent-dim: #2a8fc4;
  --accent-glow: rgba(61, 187, 255, 0.3);
  --text: #e8f4fc;
  --text-muted: #7aa8c4;
  --text-dim: #4a7088;
  --key: #0e1e2c;
  --key-hover: #152838;
  --key-active: #1c3244;
  --op: #0c2438;
  --op-hover: #143450;
  --equals: linear-gradient(135deg, #3dbbff 0%, #1a8fd4 100%);
  --equals-text: #031018;
}

[data-skin="emerald"] {
  --bg: #06120c;
  --bg-elevated: #0a1a12;
  --glass: rgba(10, 30, 20, 0.75);
  --glass-border: rgba(80, 220, 140, 0.1);
  --accent: #34d399;
  --accent-dim: #22a06b;
  --accent-glow: rgba(52, 211, 153, 0.28);
  --text: #e8f8f0;
  --text-muted: #7ab898;
  --text-dim: #4a7860;
  --key: #0e2218;
  --key-hover: #163028;
  --key-active: #1c3c30;
  --op: #0c2818;
  --op-hover: #143820;
  --equals: linear-gradient(135deg, #34d399 0%, #1fa86a 100%);
  --equals-text: #031208;
}

[data-skin="rose"] {
  --bg: #12080c;
  --bg-elevated: #1a0e14;
  --glass: rgba(30, 14, 22, 0.75);
  --glass-border: rgba(255, 140, 180, 0.1);
  --accent: #f472b6;
  --accent-dim: #db2777;
  --accent-glow: rgba(244, 114, 182, 0.28);
  --text: #fce8f0;
  --text-muted: #c48aa4;
  --text-dim: #785060;
  --key: #221018;
  --key-hover: #2e1822;
  --key-active: #3a2030;
  --op: #281018;
  --op-hover: #382028;
  --equals: linear-gradient(135deg, #f472b6 0%, #db2777 100%);
  --equals-text: #1a0810;
}

[data-skin="amber"] {
  --bg: #120e06;
  --bg-elevated: #1a160c;
  --glass: rgba(30, 24, 10, 0.75);
  --glass-border: rgba(255, 180, 50, 0.12);
  --accent: #fbbf24;
  --accent-dim: #d97706;
  --accent-glow: rgba(251, 191, 36, 0.3);
  --text: #fef6e0;
  --text-muted: #c4a86a;
  --text-dim: #786840;
  --key: #221c10;
  --key-hover: #2e2616;
  --key-active: #3a3020;
  --op: #2a200c;
  --op-hover: #3a2e14;
  --equals: linear-gradient(135deg, #fbbf24 0%, #d97706 100%);
  --equals-text: #1a1204;
}

[data-skin="violet"] {
  --bg: #0c0814;
  --bg-elevated: #140e20;
  --glass: rgba(22, 14, 36, 0.75);
  --glass-border: rgba(180, 140, 255, 0.12);
  --accent: #a78bfa;
  --accent-dim: #7c3aed;
  --accent-glow: rgba(167, 139, 250, 0.3);
  --text: #f0eafc;
  --text-muted: #a090c4;
  --text-dim: #605080;
  --key: #1a1428;
  --key-hover: #241c34;
  --key-active: #2e2440;
  --op: #1c1430;
  --op-hover: #2a1e44;
  --equals: linear-gradient(135deg, #a78bfa 0%, #7c3aed 100%);
  --equals-text: #0c0818;
}

[data-skin="paper"] {
  --bg: #f4f2ee;
  --bg-elevated: #ffffff;
  --glass: rgba(255, 255, 255, 0.8);
  --glass-border: rgba(0, 0, 0, 0.07);
  --accent: #b45309;
  --accent-dim: #92400e;
  --accent-glow: rgba(180, 83, 9, 0.15);
  --text: #1a1916;
  --text-muted: #6b6860;
  --text-dim: #9a968c;
  --key: #ebe8e2;
  --key-hover: #e0ddd5;
  --key-active: #d5d2c9;
  --op: #f5e6d4;
  --op-hover: #ebdbc0;
  --equals: linear-gradient(135deg, #b45309 0%, #92400e 100%);
  --equals-text: #fffaf5;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
}

[data-skin="snow"] {
  --bg: #f0f4f8;
  --bg-elevated: #ffffff;
  --glass: rgba(255, 255, 255, 0.85);
  --glass-border: rgba(0, 40, 80, 0.08);
  --accent: #0284c7;
  --accent-dim: #0369a1;
  --accent-glow: rgba(2, 132, 199, 0.18);
  --text: #0f172a;
  --text-muted: #64748b;
  --text-dim: #94a3b8;
  --key: #e2e8f0;
  --key-hover: #d0d8e4;
  --key-active: #c0cad8;
  --op: #dbeafe;
  --op-hover: #bfdbfe;
  --equals: linear-gradient(135deg, #0284c7 0%, #0369a1 100%);
  --equals-text: #f0f9ff;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
}

/* Light mode is handled by paper/snow skins — no global data-theme override */

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

html {
  font-size: 16px;
  -webkit-tap-highlight-color: transparent;
  height: 100%;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  min-height: 100%;
  min-height: 100dvh;
  min-height: 100svh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  margin: 0;
  width: 100%;
}

.app {
  position: relative;
  width: 100%;
  max-width: 100%;
  margin: 0 auto;
  min-height: 100dvh;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  padding: 10px 12px calc(12px + var(--safe-bottom));
  gap: 8px;
  box-sizing: border-box;
}

.ambient {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(ellipse 80% 45% at 50% -15%, color-mix(in srgb, var(--accent) 12%, transparent), transparent 65%);
}

/* ── Header ── */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  z-index: 2;
  padding: 4px 2px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
}

.brand-mark {
  color: var(--gold);
  font-size: 14px;
  opacity: 0.9;
}

.brand-name {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--text-muted);
}

.header-actions {
  display: flex;
  gap: 4px;
}

.icon-btn {
  width: 36px;
  height: 36px;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--text-muted);
  display: grid;
  place-items: center;
  cursor: pointer;
  transition: color 0.15s, background 0.15s;
}

.icon-btn:hover {
  color: var(--gold);
  background: rgba(201, 162, 39, 0.08);
}

.icon-btn:active {
  transform: scale(0.94);
}

/* ── Mode tabs ── */
.mode-tabs {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  z-index: 2;
  padding: 2px 0;
}

.mode-tabs::-webkit-scrollbar { display: none; }

.mode-tab {
  flex-shrink: 0;
  border: none;
  background: transparent;
  color: var(--text-dim);
  font-family: var(--font);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.04em;
  padding: 8px 12px;
  border-radius: 20px;
  cursor: pointer;
  transition: color 0.2s, background 0.2s;
}

.mode-tab:hover { color: var(--text-muted); }

.mode-tab.active {
  color: var(--text);
  background: rgba(255, 255, 255, 0.08);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--accent) 40%, transparent);
}

/* ── Display ── */
.display {
  position: relative;
  z-index: 2;
  padding: 20px 20px 18px;
  border-radius: var(--radius);
  min-height: 110px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  align-items: flex-end;
  gap: 6px;
}

.glass {
  background: var(--glass);
  backdrop-filter: blur(28px) saturate(1.35);
  -webkit-backdrop-filter: blur(28px) saturate(1.35);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
}

.expression {
  font-family: var(--mono);
  font-size: 14px;
  font-weight: 400;
  color: var(--text-muted);
  min-height: 1.3em;
  text-align: right;
  word-break: break-all;
  max-width: 100%;
  opacity: 0.85;
}

.result {
  font-family: var(--mono);
  font-size: clamp(28px, 8vw, 40px);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--text);
  text-align: right;
  line-height: 1.15;
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
}

.memory-indicator {
  font-size: 10px;
  font-weight: 700;
  color: var(--gold);
  letter-spacing: 0.05em;
  opacity: 0.9;
}

/* ── Body / Panels ── */
.body {
  flex: 1;
  z-index: 2;
  display: flex;
  flex-direction: column;
  min-height: 0;
}

.panel {
  display: none;
  flex-direction: column;
  gap: 10px;
  flex: 1;
  animation: fadeIn 0.25s ease;
}

.panel.active { display: flex; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Keypad ── */
.keypad {
  display: grid;
  gap: 8px;
}

.scientific-keys {
  grid-template-columns: repeat(5, 1fr);
  gap: 6px;
}

.main-keys {
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.key {
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font);
  font-size: 17px;
  font-weight: 500;
  height: 52px;
  background: var(--key);
  color: var(--text);
  cursor: pointer;
  transition: background 0.12s, transform 0.08s, box-shadow 0.12s;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
  position: relative;
  overflow: hidden;
}

.key::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at center, rgba(255,255,255,0.08), transparent 70%);
  opacity: 0;
  transition: opacity 0.2s;
  pointer-events: none;
}

.key:hover::after { opacity: 1; }

.key:active {
  transform: scale(0.96);
  background: var(--key-active);
}

.key.num { font-variant-numeric: tabular-nums; }

.key.op {
  background: var(--op);
  color: var(--gold);
  font-size: 20px;
}

.key.op:hover { background: var(--op-hover); }

.key.util {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text);
  opacity: 0.92;
}

.key.fn {
  font-size: 12px;
  font-weight: 700;
  height: 40px;
  /* Dark orange — readable on dark keys, not yellow */
  color: #e07020 !important;
  background: #1a1a1c !important;
  letter-spacing: 0.03em;
  border: 1px solid rgba(224, 112, 32, 0.25);
}

.key.fn:hover {
  color: #ff8c38 !important;
  background: #222226 !important;
  border-color: rgba(224, 112, 32, 0.5);
}

/* Light skins: dark text on light keys */
[data-skin="paper"] .key.fn,
[data-skin="snow"] .key.fn {
  color: #c45a12 !important;
  background: #efeae3 !important;
  border: 1px solid rgba(196, 90, 18, 0.3);
}

[data-skin="paper"] .key.fn:hover,
[data-skin="snow"] .key.fn:hover {
  color: #a3480a !important;
  background: #e5dfd5 !important;
  border-color: rgba(196, 90, 18, 0.5);
}

[data-skin="paper"] .key.util,
[data-skin="snow"] .key.util {
  color: #1a1916;
  opacity: 1;
}

.key.equals {
  background: var(--equals);
  color: var(--equals-text);
  font-weight: 600;
  font-size: 22px;
  box-shadow: 0 4px 16px var(--gold-glow);
}

.key.equals:hover {
  filter: brightness(1.08);
}

.key.equals:active {
  transform: scale(0.96);
  filter: brightness(0.95);
}

.key.wide {
  grid-column: span 2;
}

/* ── Financial ── */
.fin-tabs, .base-tabs, .conv-tabs {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
}

.fin-tabs::-webkit-scrollbar,
.base-tabs::-webkit-scrollbar,
.conv-tabs::-webkit-scrollbar { display: none; }

.fin-tab, .base-tab, .conv-tab {
  flex-shrink: 0;
  border: none;
  background: transparent;
  color: var(--text-dim);
  font-family: var(--font);
  font-size: 12px;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 20px;
  cursor: pointer;
  transition: color 0.2s, background 0.2s;
}

.fin-tab.active, .base-tab.active, .conv-tab.active {
  color: var(--gold);
  background: rgba(201, 162, 39, 0.12);
}

.fin-form {
  display: none;
  flex-direction: column;
  gap: 12px;
  animation: fadeIn 0.2s ease;
}

.fin-form.active { display: flex; }

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.field label {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.field input,
.field select {
  font-family: var(--mono);
  font-size: 16px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text);
  outline: none;
  transition: border-color 0.15s;
  width: 100%;
}

.field input:focus,
.field select:focus {
  border-color: var(--gold-dim);
}

.field select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%238a8780' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

.fin-calc {
  margin-top: 4px;
  height: 48px;
}

.fin-result {
  font-family: var(--mono);
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-muted);
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: rgba(201, 162, 39, 0.06);
  border: 1px solid rgba(201, 162, 39, 0.12);
  min-height: 48px;
  white-space: pre-wrap;
}

.fin-result:empty { display: none; }

/* ── Programmer ── */
.prog-display {
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.prog-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--mono);
  font-size: 13px;
}

.base-label {
  color: var(--text-dim);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  min-width: 32px;
}

.prog-keys {
  grid-template-columns: repeat(4, 1fr);
  gap: 6px;
}

.prog-keys .key {
  height: 44px;
  font-size: 14px;
}

.hex-only { color: var(--gold) !important; }

/* ── Graph ── */
.graph-controls {
  display: flex;
  gap: 8px;
}

.graph-controls input {
  flex: 1;
  font-family: var(--mono);
  font-size: 14px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text);
  outline: none;
}

.graph-controls input:focus {
  border-color: var(--gold-dim);
}

.graph-controls .key {
  width: 80px;
  flex-shrink: 0;
  height: 44px;
  font-size: 14px;
}

.graph-canvas-wrap {
  border-radius: var(--radius);
  padding: 8px;
  flex: 1;
  min-height: 220px;
  position: relative;
}

#graph-canvas {
  width: 100% !important;
  height: 100% !important;
  min-height: 200px;
}

.graph-zoom {
  display: flex;
  gap: 8px;
  justify-content: center;
}

.graph-zoom .key {
  width: 56px;
  height: 40px;
  font-size: 16px;
}

/* ── Convert ── */
.conv-body {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.conv-row {
  display: flex;
  gap: 8px;
}

.conv-row input {
  flex: 1;
}

.conv-row select {
  width: 110px;
  flex-shrink: 0;
}

#conv-swap {
  height: 44px;
  font-size: 14px;
}

/* ── History drawer ── */
.history-drawer {
  position: fixed;
  top: 0;
  right: 0;
  width: min(320px, 85vw);
  height: 100%;
  background: var(--bg-elevated);
  border-left: 1px solid var(--glass-border);
  z-index: 100;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0.22, 1, 0.36, 1);
  display: flex;
  flex-direction: column;
  padding: 20px 16px;
  box-shadow: -12px 0 40px rgba(0, 0, 0, 0.3);
}

.history-drawer.open {
  transform: translateX(0);
}

.history-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.history-header h3 {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

.history-list {
  list-style: none;
  overflow-y: auto;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.history-list li {
  font-family: var(--mono);
  font-size: 13px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: var(--key);
  color: var(--text-muted);
  cursor: pointer;
  transition: background 0.15s;
  word-break: break-all;
}

.history-list li:hover {
  background: var(--key-hover);
  color: var(--text);
}

.history-list li .hist-result {
  color: var(--gold);
  font-weight: 500;
}

.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s, visibility 0.25s;
}

.overlay.visible {
  opacity: 1;
  visibility: visible;
}

/* ── Menu drawer ── */
.menu-drawer {
  position: fixed;
  top: 0;
  left: 0;
  width: min(300px, 82vw);
  height: 100%;
  background: var(--bg-elevated);
  border-right: 1px solid var(--glass-border);
  z-index: 100;
  transform: translateX(-100%);
  transition: transform 0.3s cubic-bezier(0.22, 1, 0.36, 1);
  display: flex;
  flex-direction: column;
  padding: 20px 16px;
  box-shadow: 12px 0 40px rgba(0, 0, 0, 0.35);
}

.menu-drawer.open {
  transform: translateX(0);
}

.menu-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.menu-header h3 {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}

.menu-nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.menu-item {
  display: flex;
  align-items: center;
  gap: 12px;
  border: none;
  background: transparent;
  color: var(--text);
  font-family: var(--font);
  font-size: 15px;
  font-weight: 500;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  text-align: left;
  transition: background 0.15s, color 0.15s;
}

.menu-item:hover {
  background: var(--key);
  color: var(--gold);
}

.menu-item:active {
  transform: scale(0.98);
}

.menu-icon {
  width: 24px;
  text-align: center;
  color: var(--gold);
  font-size: 14px;
  opacity: 0.9;
}

.menu-divider {
  height: 1px;
  background: var(--glass-border);
  margin: 14px 0;
}

.menu-footer {
  margin-top: auto;
  padding-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.menu-brand {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.menu-ver {
  font-size: 11px;
  color: var(--text-dim);
}

.menu-section-label {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-dim);
  padding: 8px 14px 6px;
}

.skin-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  padding: 4px 10px 12px;
}

.skin-swatch {
  aspect-ratio: 1;
  border-radius: 10px;
  border: 2px solid transparent;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  transition: border-color 0.15s, transform 0.1s;
  padding: 0;
}

.skin-swatch:hover { transform: scale(1.06); }
.skin-swatch.active { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent-glow); }
.skin-swatch span {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 4px;
  font-size: 8px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: rgba(255,255,255,0.85);
  text-shadow: 0 1px 2px rgba(0,0,0,0.5);
}

.skin-swatch[data-skin="lumina"] { background: linear-gradient(145deg, #0a0a0b, #c9a227); }
.skin-swatch[data-skin="obsidian"] { background: linear-gradient(145deg, #050508, #e8e8ec); }
.skin-swatch[data-skin="ocean"] { background: linear-gradient(145deg, #061018, #3dbbff); }
.skin-swatch[data-skin="emerald"] { background: linear-gradient(145deg, #06120c, #34d399); }
.skin-swatch[data-skin="rose"] { background: linear-gradient(145deg, #12080c, #f472b6); }
.skin-swatch[data-skin="amber"] { background: linear-gradient(145deg, #120e06, #fbbf24); }
.skin-swatch[data-skin="violet"] { background: linear-gradient(145deg, #0c0814, #a78bfa); }
.skin-swatch[data-skin="paper"] { background: linear-gradient(145deg, #f4f2ee, #b45309); }
.skin-swatch[data-skin="paper"] span,
.skin-swatch[data-skin="snow"] span { color: rgba(0,0,0,0.65); text-shadow: none; }
.skin-swatch[data-skin="snow"] { background: linear-gradient(145deg, #f0f4f8, #0284c7); }

.display-meta {
  position: absolute;
  top: 10px;
  left: 14px;
  display: flex;
  gap: 8px;
  align-items: center;
}

.angle-mode,
.notation-badge {
  -webkit-appearance: none;
  appearance: none;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: #c45a12 !important;
  -webkit-text-fill-color: #c45a12 !important;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 6px;
  border: 1px solid #3d2a18 !important;
  background: #141416 !important;
  background-color: #141416 !important;
  font-family: var(--font);
  opacity: 1 !important;
  box-shadow: none !important;
}

.angle-mode:hover,
.notation-badge:hover {
  color: #e07020 !important;
  -webkit-text-fill-color: #e07020 !important;
  border-color: #c45a12 !important;
  background: #1c1c20 !important;
  background-color: #1c1c20 !important;
}

.toast {
  position: fixed;
  bottom: calc(24px + var(--safe-bottom));
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--bg-elevated);
  color: var(--text);
  border: 1px solid var(--glass-border);
  padding: 10px 18px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s, transform 0.25s;
  box-shadow: var(--shadow);
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ── Keys — mobile-first density ── */
.key {
  height: 48px;
  font-size: 16px;
}

.key.fn {
  height: 36px;
  font-size: 11px;
}

.scientific-keys {
  gap: 5px;
}

.main-keys {
  gap: 7px;
}

/* ── Responsive ── */
@media (min-width: 400px) {
  .key { height: 52px; font-size: 17px; }
  .key.fn { height: 40px; font-size: 12px; }
  .scientific-keys { gap: 6px; }
  .main-keys { gap: 8px; }
}

@media (min-width: 480px) {
  .app {
    padding: 16px 16px 20px;
    gap: 10px;
    max-width: 440px;
  }

  .key { height: 56px; }
  .key.fn { height: 42px; }
  .scientific-keys { gap: 8px; }
  .main-keys { gap: 10px; }
}

@media (min-width: 768px) {
  .app {
    max-width: 480px;
    margin-top: 24px;
    margin-bottom: 24px;
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    background: var(--bg-elevated);
    box-shadow: var(--shadow);
    min-height: auto;
    padding: 20px 18px 24px;
  }
}

@media (min-width: 1024px) {
  .app {
    max-width: 520px;
  }
}

/* Reduce motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* ── Formulas ── */
.formula-cats {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
}
.formula-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
  max-height: 40vh;
  overflow-y: auto;
}
.formula-card {
  text-align: left;
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  cursor: pointer;
  font-family: var(--font);
  transition: background 0.15s, border-color 0.15s;
}
.formula-card:hover {
  border-color: var(--accent-dim);
  background: var(--key-hover);
}
.formula-card .fname {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
}
.formula-card .fexpr {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent);
  margin-top: 4px;
}
.formula-card .fdesc {
  font-size: 11px;
  color: var(--text-dim);
  margin-top: 4px;
}
.formula-run {
  padding: 14px;
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.formula-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
}
.graph-meta {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--text-muted);
  min-height: 1.2em;
  padding: 0 4px;
}
.expression[contenteditable="true"] {
  outline: none;
  min-height: 1.3em;
  width: 100%;
  cursor: text;
}
.expression[contenteditable="true"]:focus {
  color: var(--text);
  opacity: 1;
}
.key.haptic-pulse {
  animation: keyPulse 0.12s ease;
}
@keyframes keyPulse {
  0% { transform: scale(1); }
  50% { transform: scale(0.94); }
  100% { transform: scale(1); }
}


/* ── Design option controls ── */
.design-controls {
  padding: 4px 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.design-row {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.design-row label {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-dim);
  letter-spacing: 0.04em;
  display: flex;
  justify-content: space-between;
}
.design-row label span {
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}
.design-row input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  background: var(--key);
  outline: none;
}
.design-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  box-shadow: 0 0 10px var(--accent-glow);
}
.design-toggles {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.design-chip {
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text-muted);
  font-family: var(--font);
  font-size: 11px;
  font-weight: 500;
  padding: 7px 12px;
  border-radius: 20px;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s, background 0.15s;
}
.design-chip.active {
  border-color: var(--accent-dim);
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 12%, transparent);
}

/* Extra skins */
.skin-swatch[data-skin="neon"] { background: linear-gradient(145deg, #050510, #22d3ee); }
.skin-swatch[data-skin="carbon"] { background: linear-gradient(145deg, #111, #666); }
.skin-swatch[data-skin="sunset"] { background: linear-gradient(145deg, #1a0a08, #fb7185 40%, #fbbf24); }

[data-skin="neon"] {
  --bg: #03040a;
  --bg-elevated: #080a14;
  --glass: rgba(8, 12, 28, 0.72);
  --glass-border: rgba(34, 211, 238, 0.15);
  --accent: #22d3ee;
  --accent-dim: #0891b2;
  --accent-glow: rgba(34, 211, 238, 0.4);
  --text: #e0f7fa;
  --text-muted: #7dd3e0;
  --text-dim: #3d7a88;
  --key: #0a1020;
  --key-hover: #121c30;
  --key-active: #1a2840;
  --op: #0a1828;
  --op-hover: #122838;
  --equals: linear-gradient(135deg, #22d3ee 0%, #0891b2 100%);
  --equals-text: #021018;
}
[data-skin="carbon"] {
  --bg: #0c0c0c;
  --bg-elevated: #141414;
  --glass: rgba(20, 20, 20, 0.8);
  --glass-border: rgba(255,255,255,0.07);
  --accent: #a3a3a3;
  --accent-dim: #737373;
  --accent-glow: rgba(163,163,163,0.2);
  --text: #fafafa;
  --text-muted: #a3a3a3;
  --text-dim: #525252;
  --key: #1a1a1a;
  --key-hover: #242424;
  --key-active: #2e2e2e;
  --op: #1f1f1f;
  --op-hover: #2a2a2a;
  --equals: linear-gradient(135deg, #d4d4d4 0%, #a3a3a3 100%);
  --equals-text: #0a0a0a;
}
[data-skin="sunset"] {
  --bg: #120808;
  --bg-elevated: #1a0e0c;
  --glass: rgba(30, 14, 12, 0.75);
  --glass-border: rgba(251, 113, 133, 0.15);
  --accent: #fb7185;
  --accent-dim: #e11d48;
  --accent-glow: rgba(251, 113, 133, 0.35);
  --text: #fff1f2;
  --text-muted: #fda4af;
  --text-dim: #9f1239;
  --key: #221010;
  --key-hover: #2e1818;
  --key-active: #3a2020;
  --op: #2a1010;
  --op-hover: #3a1818;
  --equals: linear-gradient(135deg, #fb7185 0%, #fbbf24 100%);
  --equals-text: #1a0808;
}

/* Compact density */
[data-density="compact"] .key { height: 42px; font-size: 15px; }
[data-density="compact"] .key.fn { height: 32px; font-size: 10px; }
[data-density="compact"] .main-keys { gap: 5px; }
[data-density="compact"] .scientific-keys { gap: 4px; }

/* Soft corners option */
[data-radius="soft"] {
  --radius: 20px;
  --radius-sm: 14px;
}
[data-radius="sharp"] {
  --radius: 6px;
  --radius-sm: 4px;
}

/* High contrast mode */
body.high-contrast {
  --glass-border: rgba(255,255,255,0.25);
  --text-muted: var(--text);
  --text-dim: var(--text-muted);
}
body.high-contrast .key {
  border: 1px solid var(--glass-border);
}
body.high-contrast .display {
  outline: 2px solid var(--accent);
}
body.high-contrast .mode-tab.active {
  outline: 2px solid var(--accent);
}

/* Focus visible for keyboard users */
.key:focus-visible,
.icon-btn:focus-visible,
.mode-tab:focus-visible,
.menu-item:focus-visible,
.design-chip:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
}

.result.error {
  color: #f87171;
  font-size: clamp(18px, 5vw, 24px);
}
/* notation-badge styled with .angle-mode */

.const-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 8px;
}
.const-chip {
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text-muted);
  font-family: var(--mono);
  font-size: 11px;
  padding: 6px 10px;
  border-radius: 8px;
  cursor: pointer;
}
.const-chip:hover { color: var(--accent); border-color: var(--accent-dim); }


/* === FORCE SCI KEY CONTRAST (last rule wins) === */
button.key.fn,
#scientificKeys button.key,
.keypad.scientific-keys .key {
  color: #c45a12 !important;
  background-color: #0e0e10 !important;
  background-image: none !important;
  font-weight: 700 !important;
  -webkit-text-fill-color: #c45a12 !important;
  text-shadow: none !important;
  opacity: 1 !important;
  border: 1px solid #3d2a18 !important;
}
button.key.fn:hover,
#scientificKeys button.key:hover,
.keypad.scientific-keys .key:hover {
  color: #e07020 !important;
  -webkit-text-fill-color: #e07020 !important;
  background-color: #161618 !important;
  border-color: #c45a12 !important;
}
/* Light skins still need dark orange on light gray, not yellow */
[data-skin="paper"] button.key.fn,
[data-skin="snow"] button.key.fn {
  color: #9a3f0a !important;
  -webkit-text-fill-color: #9a3f0a !important;
  background-color: #e8e4dc !important;
  border: 1px solid #c45a12 !important;
}


/* === FORCE DISPLAY META BADGES (DEG / NORM) === */
.display-meta button,
button.angle-mode,
button.notation-badge,
#angleMode,
#notationMode {
  -webkit-appearance: none !important;
  appearance: none !important;
  color: #c45a12 !important;
  -webkit-text-fill-color: #c45a12 !important;
  background: #141416 !important;
  background-color: #141416 !important;
  border: 1px solid #3d2a18 !important;
  border-radius: 6px !important;
  padding: 4px 8px !important;
  font-size: 10px !important;
  font-weight: 700 !important;
  opacity: 1 !important;
  box-shadow: none !important;
}
.display-meta button:hover,
button.angle-mode:hover,
button.notation-badge:hover,
#angleMode:hover,
#notationMode:hover {
  color: #e07020 !important;
  -webkit-text-fill-color: #e07020 !important;
  background: #1c1c20 !important;
  border-color: #c45a12 !important;
}

/* Advanced UI */
.expr-wrap { width: 100%; text-align: right; }
.error-line {
  font-size: 11px;
  color: #f87171;
  margin-top: 4px;
  text-align: right;
  font-family: var(--mono);
}
.expression[data-placeholder]:empty::before {
  content: attr(data-placeholder);
  color: var(--text-dim);
  pointer-events: none;
}
.amort-wrap {
  max-height: 220px;
  overflow: auto;
  font-size: 11px;
  font-family: var(--mono);
  margin-top: 8px;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
}
.amort-wrap table { width: 100%; border-collapse: collapse; }
.amort-wrap th, .amort-wrap td {
  padding: 4px 6px;
  text-align: right;
  border-bottom: 1px solid var(--glass-border);
}
.amort-wrap th:first-child, .amort-wrap td:first-child { text-align: left; }
.install-banner {
  position: relative;
  z-index: 5;
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: #141416;
  border: 1px solid #3d2a18;
  color: #e07020;
  font-size: 13px;
}
.install-banner button {
  border: none;
  border-radius: 8px;
  padding: 6px 12px;
  font-weight: 600;
  cursor: pointer;
  background: #c45a12;
  color: #fff;
}
.install-banner .text-btn {
  background: transparent;
  color: var(--text-muted);
}
#mtg-chart { width: 100%; margin-top: 8px; border-radius: 8px; }

#toolList { max-height: 45vh; }
#toolCats { margin-bottom: 8px; }

.tool-search-row {
  display: flex;
  gap: 8px;
  align-items: center;
  margin-bottom: 8px;
}
.tool-search-row input {
  flex: 1;
  font-family: var(--font);
  font-size: 14px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text);
  outline: none;
}
.tool-search-row input:focus { border-color: #c45a12; }
.tool-count {
  font-size: 11px;
  color: var(--text-dim);
  white-space: nowrap;
}
#toolList { max-height: 42vh; }

.tool-run-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}
.tool-actions {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-top: 4px;
}
.tool-actions .key { flex: 1; min-width: 70px; }
.tool-quick {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}
.tool-chip {
  border: 1px solid var(--glass-border);
  background: var(--key);
  color: var(--text-muted);
  font-size: 11px;
  padding: 6px 10px;
  border-radius: 999px;
  cursor: pointer;
  font-family: var(--font);
}
.tool-chip:hover { color: #e07020; border-color: #c45a12; }
.tool-chip.fav { color: #e07020; }
.formula-card.fav .fname::before { content: "★ "; color: #c45a12; }

.install-banner[hidden],
.install-banner.is-dismissed {
  display: none !important;
}