:root {
  --bg: #0a0a0f;
  --bg-2: #111118;
  --bg-3: #16161f;
  --bg-4: #1c1c28;
  --border: #252532;
  --border-hi: #35354a;
  --text: #e4e4ef;
  --text-dim: #8a8aa0;
  --text-mute: #5a5a70;
  --accent: #4dd4c6;
  --accent-2: #6b8aff;
  --accent-glow: rgba(77, 212, 198, 0.25);
  --danger: #ff5d7a;
  --radius: 8px;
  --radius-sm: 4px;
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", system-ui, sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", "Fira Code", Menlo, Monaco, monospace;
}

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

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 14px;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(77, 212, 198, 0.06), transparent 60%),
    radial-gradient(900px 500px at 110% 110%, rgba(107, 138, 255, 0.05), transparent 60%);
  pointer-events: none;
  z-index: 0;
}

.app {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-rows: auto 1fr;
  height: 100vh;
}

/* Topbar */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg-2), var(--bg));
}
.brand { display: flex; align-items: center; gap: 12px; }
.logo { color: var(--accent); display: flex; }
.brand h1 {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.3px;
}
.brand p {
  font-size: 11px;
  color: var(--text-mute);
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
  text-transform: uppercase;
}
.topbar-actions { display: flex; gap: 6px; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border: 1px solid var(--border);
  background: var(--bg-3);
  color: var(--text);
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 12px;
  cursor: pointer;
  transition: all 0.15s ease;
}
.btn:hover { border-color: var(--accent); color: var(--accent); background: var(--bg-4); }
.btn:active { transform: translateY(1px); }
.btn-ghost { background: transparent; border-color: transparent; }
.btn-ghost:hover { background: var(--bg-3); border-color: var(--border); }
.btn-icon {
  width: 32px; height: 32px;
  padding: 0;
  justify-content: center;
  border-radius: var(--radius-sm);
}
.btn-accent {
  background: var(--accent);
  color: #0a0a0f;
  border-color: var(--accent);
  font-weight: 600;
}
.btn-accent:hover { background: #3cc0b2; color: #0a0a0f; }

/* Main grid */
.main {
  display: grid;
  grid-template-columns: 220px 1fr 280px;
  min-height: 0;
}

/* Sidebar */
.sidebar {
  border-right: 1px solid var(--border);
  background: var(--bg-2);
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.sidebar-title {
  padding: 14px 16px 10px;
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-mute);
  letter-spacing: 1.2px;
  text-transform: uppercase;
}
.illusion-list {
  list-style: none;
  overflow-y: auto;
  flex: 1;
  padding: 0 8px;
}
.illusion-list li {
  padding: 10px 12px;
  border-radius: var(--radius);
  cursor: pointer;
  margin-bottom: 2px;
  border: 1px solid transparent;
  transition: all 0.15s ease;
}
.illusion-list li:hover { background: var(--bg-3); }
.illusion-list li.active {
  background: var(--bg-4);
  border-color: var(--accent);
  box-shadow: inset 0 0 0 1px var(--accent-glow), 0 0 20px var(--accent-glow);
}
.illusion-list li .ill-name {
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 2px;
}
.illusion-list li.active .ill-name { color: var(--accent); }
.illusion-list li .ill-name-en {
  font-size: 10px;
  color: var(--text-mute);
  font-family: var(--font-mono);
  letter-spacing: 0.3px;
}
.illusion-list li .ill-num {
  font-size: 10px;
  color: var(--text-mute);
  font-family: var(--font-mono);
  float: right;
  margin-top: 2px;
}
.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  background: var(--bg-2);
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.stat-row {
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-mute);
}
.stat-row strong { color: var(--accent); }

/* Stage */
.stage {
  display: flex;
  flex-direction: column;
  min-height: 0;
  min-width: 0;
  background: var(--bg);
}
.stage-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  padding: 14px 20px 10px;
  border-bottom: 1px solid var(--border);
}
.stage-header h2 {
  font-size: 18px;
  font-weight: 600;
  letter-spacing: 0.3px;
}
.subtitle {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-mute);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-top: 2px;
}
.stage-controls { display: flex; gap: 6px; }

.canvas-wrap {
  position: relative;
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  overflow: hidden;
  background:
    linear-gradient(var(--bg), var(--bg)),
    repeating-linear-gradient(0deg, transparent 0 19px, rgba(255,255,255,0.02) 19px 20px),
    repeating-linear-gradient(90deg, transparent 0 19px, rgba(255,255,255,0.02) 19px 20px);
  background-blend-mode: normal, normal, normal;
}
.canvas-wrap::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    repeating-linear-gradient(0deg, transparent 0 19px, rgba(255,255,255,0.015) 19px 20px),
    repeating-linear-gradient(90deg, transparent 0 19px, rgba(255,255,255,0.015) 19px 20px);
  pointer-events: none;
}
#canvas {
  max-width: 100%;
  max-height: 100%;
  border-radius: var(--radius);
  box-shadow: 0 0 0 1px var(--border-hi), 0 20px 60px rgba(0,0,0,0.5);
  background: #000;
  display: block;
}
.canvas-overlay {
  position: absolute;
  top: 24px; right: 24px;
  pointer-events: none;
}
.recording-indicator {
  display: flex;
  align-items: center;
  gap: 8px;
  background: rgba(10, 10, 15, 0.85);
  border: 1px solid var(--danger);
  color: var(--danger);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 11px;
}
.rec-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--danger);
  animation: pulse 1s infinite;
}
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.3} }

.explanation {
  border-top: 1px solid var(--border);
  padding: 14px 20px;
  background: var(--bg-2);
  max-height: 140px;
  overflow-y: auto;
}
.exp-title {
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--accent);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.exp-title::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 8px var(--accent);
}
#explanation-text {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-dim);
}

/* Controls panel */
.controls {
  border-left: 1px solid var(--border);
  background: var(--bg-2);
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.controls-title {
  padding: 14px 16px 10px;
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-mute);
  letter-spacing: 1.2px;
  text-transform: uppercase;
  border-bottom: 1px solid var(--border);
}
.controls-body {
  padding: 16px;
  overflow-y: auto;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.ctrl-group { display: flex; flex-direction: column; gap: 6px; }
.ctrl-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-dim);
  letter-spacing: 0.5px;
}
.ctrl-label .ctrl-value {
  color: var(--accent);
  font-weight: 500;
  background: var(--bg-3);
  padding: 1px 6px;
  border-radius: 3px;
  min-width: 36px;
  text-align: center;
}

/* Range slider */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--bg-4);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-2);
  box-shadow: 0 0 0 1px var(--accent), 0 0 10px var(--accent-glow);
  cursor: pointer;
  transition: transform 0.1s;
}
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.2); }
input[type="range"]::-moz-range-thumb {
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-2);
  box-shadow: 0 0 0 1px var(--accent);
  cursor: pointer;
}

/* Color input */
input[type="color"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-3);
  cursor: pointer;
  padding: 2px;
}
input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
input[type="color"]::-webkit-color-swatch { border: none; border-radius: 2px; }

/* Toggle */
.toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  user-select: none;
}
.toggle-track {
  width: 32px; height: 18px;
  background: var(--bg-4);
  border: 1px solid var(--border);
  border-radius: 10px;
  position: relative;
  transition: all 0.2s;
}
.toggle-track::after {
  content: '';
  position: absolute;
  top: 2px; left: 2px;
  width: 12px; height: 12px;
  border-radius: 50%;
  background: var(--text-mute);
  transition: all 0.2s;
}
.toggle input { display: none; }
.toggle input:checked + .toggle-track {
  background: var(--accent);
  border-color: var(--accent);
}
.toggle input:checked + .toggle-track::after {
  left: 16px;
  background: #0a0a0f;
}
.toggle-label {
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-dim);
  letter-spacing: 0.5px;
}

/* Select */
select {
  width: 100%;
  padding: 6px 10px;
  background: var(--bg-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 11px;
  cursor: pointer;
  outline: none;
}
select:focus { border-color: var(--accent); }

/* Fullscreen overlay */
.fullscreen-overlay {
  position: fixed;
  inset: 0;
  background: #000;
  z-index: 999;
  display: none;
  align-items: center;
  justify-content: center;
}
.fullscreen-overlay.active { display: flex; }
#fullscreen-canvas { max-width: 100%; max-height: 100%; }
.fs-exit {
  position: absolute;
  top: 20px; right: 20px;
  padding: 8px 16px;
  background: rgba(0,0,0,0.7);
  border: 1px solid var(--border-hi);
  color: var(--text);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 11px;
  cursor: pointer;
  backdrop-filter: blur(8px);
}
.fs-exit:hover { border-color: var(--accent); color: var(--accent); }

/* Scrollbar */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--border-hi); }

/* Responsive */
@media (max-width: 1024px) {
  .main { grid-template-columns: 180px 1fr 240px; }
}
@media (max-width: 768px) {
  .main { grid-template-columns: 1fr; grid-template-rows: auto 1fr auto; }
  .sidebar { display: none; }
  .controls { max-height: 40vh; }
}