:root {
  --bg: #09090b;
  --surface: #121215;
  --surface-subtle: #18181b;
  --border: #27272a;
  --border-strong: #3f3f46;
  --text: #fafafa;
  --text-muted: #a1a1aa;
  --ring: #52525b;
  --font-sans: 'Geist', -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: 'Geist Mono', ui-monospace, monospace;
}

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

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 40px 20px 80px;
  -webkit-font-smoothing: antialiased;
}

.app-shell {
  width: 100%;
  max-width: 880px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  border-bottom: 1px solid var(--border);
  padding-bottom: 20px;
}

.title-group h1 { font-size: 20px; font-weight: 600; letter-spacing: -0.02em; }
.title-group p { color: var(--text-muted); font-size: 14px; margin-top: 4px; }

.btn-secondary {
  background: var(--surface-subtle);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all 0.15s ease;
  font-family: inherit;
  user-select: none;
}

.btn-secondary:hover { background: var(--border); }
.btn-secondary.active { border-color: var(--text); background: var(--border); color: #fff; }

.preview-canvas {
  background: #000;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 40px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  background-image: radial-gradient(var(--border) 1px, transparent 1px);
  background-size: 16px 16px;
  transition: background-color 0.2s ease;
}

.preview-canvas.light-mode {
  background-color: #ffffff;
  background-image: radial-gradient(#e4e4e7 1px, transparent 1px);
}

.badge-preview {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font-size: 12px;
  line-height: 1;
  padding: 4px 10px;
  border-radius: 4px;
  border: 1px solid transparent;
  user-select: none;
  transition: all 0.1s ease;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.card-title {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

.controls-row {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 12px;
}

@media (max-width: 700px) {
  .controls-row { grid-template-columns: 1fr; }
}

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

label { font-size: 12px; font-weight: 500; color: var(--text-muted); }

input[type="text"] {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  padding: 8px 12px;
  font-size: 13px;
  outline: none;
  font-family: inherit;
}

input[type="text"]:focus { border-color: var(--ring); }

.section-header-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.collapsible-panel {
  display: none;
  background: var(--surface-subtle);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
}

.collapsible-panel.open { display: block; }

.decorations-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 8px;
}

.toggle-chip {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 8px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  transition: all 0.15s ease;
}

.toggle-chip:hover { color: var(--text); background: var(--border); }
.toggle-chip.active {
  color: #fff;
  border-color: var(--text-muted);
  background: rgba(255,255,255,0.08);
}

.toggle-indicator {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--border-strong);
}

.toggle-chip.active .toggle-indicator {
  background: #38bdf8;
  box-shadow: 0 0 6px #38bdf8;
}

.palette-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(64px, 1fr));
  gap: 6px;
}

.preset-chip {
  height: 28px;
  border-radius: 4px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 500;
  border: 1px solid transparent;
  transition: transform 0.1s ease;
}

.preset-chip:hover { transform: scale(1.03); }
.preset-chip.active { border-color: #fff; }

.custom-picker-panel {
  display: none;
  background: var(--surface-subtle);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  flex-direction: column;
  gap: 14px;
}

.custom-picker-panel.open { display: flex; }

.color-map {
  width: 100%;
  height: 140px;
  border-radius: 6px;
  position: relative;
  cursor: crosshair;
  overflow: hidden;
}

.color-map-cursor {
  width: 12px;
  height: 12px;
  border: 2px solid #fff;
  border-radius: 50%;
  position: absolute;
  transform: translate(-50%, -50%);
  pointer-events: none;
  box-shadow: 0 0 4px rgba(0,0,0,0.6);
}

.slider-track {
  width: 100%;
  height: 10px;
  border-radius: 5px;
  position: relative;
  cursor: pointer;
}

.hue-track {
  background: linear-gradient(to right, #f00 0%, #ff0 17%, #0f0 33%, #0ff 50%, #00f 67%, #f0f 83%, #f00 100%);
}

.alpha-track {
  background: linear-gradient(to right, rgba(255,255,255,0.05), rgba(255,255,255,1));
}

.slider-handle {
  width: 14px;
  height: 14px;
  border: 2px solid #fff;
  background: #18181b;
  border-radius: 50%;
  position: absolute;
  top: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  box-shadow: 0 1px 3px rgba(0,0,0,0.5);
}

.slider-val-row {
  display: flex;
  justify-content: space-between;
}

.val-badge {
  font-size: 12px;
  font-family: var(--font-mono);
}

.picker-values-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

.picker-values-row input {
  width: 110px;
}

.color-chip-preview {
  width: 30px;
  height: 30px;
  border-radius: 4px;
  border: 1px solid var(--border-strong);
  flex-shrink: 0;
}

.tabs-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.tabs-header {
  display: flex;
  background: var(--surface-subtle);
  border-bottom: 1px solid var(--border);
  padding: 4px 6px 0;
  gap: 4px;
}

.tab-btn {
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-muted);
  padding: 8px 14px;
  font-size: 12px;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  border-radius: 4px 4px 0 0;
  transition: all 0.15s ease;
}

.tab-btn:hover { color: var(--text); background: rgba(255,255,255,0.02); }
.tab-btn.active {
  color: var(--text);
  border-bottom-color: var(--text);
  background: rgba(255,255,255,0.04);
}

.tab-panel {
  display: none;
  flex-direction: column;
}

.tab-panel.active { display: flex; }

.code-topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 14px;
  background: rgba(255,255,255,0.015);
  border-bottom: 1px solid var(--border);
}

.code-desc { font-size: 11px; color: var(--text-muted); }

pre {
  margin: 0;
  padding: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.5;
  color: #e4e4e7;
  overflow-x: auto;
  background: #101012;
}