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

:root {
  --bg: #060608;
  --pcb-green: #2d5a27;
  --pcb-light: #3a7a32;
  --terminal-green: #00ff41;
  --oled-cyan: #00ffcc;
  --oled-white: #e0ffe8;
  --dark-panel: #0d0f0d;
  --text-dim: #5a7a5a;
  --accent: #00ff41;
}

body {
  background: var(--bg);
  color: var(--terminal-green);
  font-family: 'VT323', monospace;
  overflow-x: hidden;
  min-height: 100vh;
}

#app-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 10px 16px 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

header {
  text-align: center;
  margin-bottom: 12px;
  width: 100%;
}

header h1 {
  font-family: 'Press Start 2P', cursive;
  font-size: 18px;
  color: var(--terminal-green);
  text-shadow: 0 0 20px rgba(0,255,65,0.5), 0 0 40px rgba(0,255,65,0.2);
  margin-bottom: 6px;
  letter-spacing: 1px;
}

header h1 .emoji {
  font-family: sans-serif;
}

.subtitle {
  font-size: 16px;
  color: var(--text-dim);
  letter-spacing: 2px;
}

#status-bar {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-top: 8px;
  font-size: 15px;
}

.status-item {
  background: #0a120a;
  border: 1px solid #1a2a1a;
  padding: 3px 10px;
  border-radius: 3px;
  font-size: 14px;
}

.upload-zone {
  width: 100%;
  max-width: 600px;
  border: 2px dashed var(--pcb-light);
  border-radius: 8px;
  padding: 16px;
  text-align: center;
  margin-bottom: 12px;
  background: rgba(45,90,39,0.08);
  transition: all 0.3s;
  cursor: pointer;
}

.upload-zone.dragover {
  border-color: var(--terminal-green);
  background: rgba(0,255,65,0.08);
  box-shadow: 0 0 30px rgba(0,255,65,0.15);
}

.upload-inner p {
  margin: 4px 0;
  font-size: 18px;
}

.upload-sub {
  font-size: 14px !important;
  color: var(--text-dim);
}

.upload-icon {
  font-size: 28px;
  font-family: sans-serif;
}

.file-btn {
  display: inline-block;
  margin-top: 8px;
  padding: 6px 16px;
  background: var(--pcb-green);
  border: 1px solid var(--pcb-light);
  color: var(--terminal-green);
  font-family: 'Press Start 2P', cursive;
  font-size: 10px;
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.2s;
}

.file-btn:hover {
  background: var(--pcb-light);
  box-shadow: 0 0 12px rgba(0,255,65,0.3);
}

#game-selector {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  font-size: 16px;
}

#game-selector label {
  font-family: 'Press Start 2P', cursive;
  font-size: 10px;
  color: var(--text-dim);
}

#game-select {
  background: #0a120a;
  color: var(--terminal-green);
  border: 1px solid var(--pcb-green);
  padding: 6px 12px;
  font-family: 'VT323', monospace;
  font-size: 18px;
  border-radius: 4px;
  cursor: pointer;
}

#game-select option {
  background: #0a0f0a;
}

#main-area {
  position: relative;
  margin-bottom: 8px;
}

#canvas {
  display: block;
  border-radius: 8px;
}

#keyboard-hint {
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 10px;
  text-align: center;
}

#keyboard-hint p {
  font-size: 14px;
}

#buzzer-controls {
  background: var(--dark-panel);
  border: 1px solid #1a2a1a;
  border-radius: 6px;
  padding: 10px 16px;
  width: 100%;
  max-width: 500px;
  margin-bottom: 10px;
}

.buzzer-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 6px;
}

.buzzer-title {
  font-family: 'Press Start 2P', cursive;
  font-size: 10px;
}

#buzzer-freq, #buzzer-note {
  font-size: 16px;
  color: var(--oled-cyan);
}

#waveform-canvas {
  width: 100%;
  height: 50px;
  background: #000;
  border: 1px solid #1a2a1a;
  border-radius: 3px;
  margin-bottom: 8px;
}

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

.buzzer-row label {
  font-family: 'Press Start 2P', cursive;
  font-size: 9px;
  color: var(--text-dim);
}

#volume-slider {
  flex: 1;
  accent-color: var(--terminal-green);
  height: 6px;
}

#mute-btn {
  background: none;
  border: 1px solid #1a2a1a;
  color: var(--terminal-green);
  font-size: 18px;
  cursor: pointer;
  padding: 2px 8px;
  border-radius: 4px;
  font-family: sans-serif;
}

#cpu-toggle-btn {
  background: var(--dark-panel);
  border: 1px solid #1a2a1a;
  color: var(--text-dim);
  font-family: 'Press Start 2P', cursive;
  font-size: 9px;
  padding: 6px 20px;
  cursor: pointer;
  border-radius: 4px;
  margin-bottom: 4px;
  transition: all 0.2s;
  width: 100%;
  max-width: 500px;
}

#cpu-toggle-btn:hover {
  border-color: var(--pcb-light);
  color: var(--terminal-green);
}

#cpu-panel {
  background: var(--dark-panel);
  border: 1px solid #1a2a1a;
  border-radius: 6px;
  padding: 12px 16px;
  width: 100%;
  max-width: 500px;
  margin-bottom: 12px;
  overflow: hidden;
  transition: max-height 0.4s ease, opacity 0.3s, padding 0.3s;
}

#cpu-panel.collapsed {
  max-height: 0;
  opacity: 0;
  padding: 0 16px;
  border: none;
}

#cpu-panel:not(.collapsed) {
  max-height: 600px;
  opacity: 1;
}

.cpu-section h3 {
  font-family: 'Press Start 2P', cursive;
  font-size: 8px;
  color: var(--text-dim);
  margin-bottom: 6px;
  letter-spacing: 1px;
}

.cpu-section {
  margin-bottom: 10px;
}

#registers-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 3px;
  font-size: 13px;
  font-family: 'VT323', monospace;
}

.reg-cell {
  background: #000;
  padding: 2px 5px;
  border-radius: 2px;
  border: 1px solid #111;
  transition: background 0.15s;
}

.reg-cell.flash {
  background: rgba(0,255,65,0.2);
  border-color: var(--terminal-green);
}

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

.reg-val {
  color: var(--oled-cyan);
}

#memory-viewer {
  background: #000;
  padding: 6px;
  border-radius: 3px;
  font-size: 12px;
  font-family: 'VT323', monospace;
  color: var(--text-dim);
  max-height: 100px;
  overflow-y: auto;
  line-height: 1.5;
  border: 1px solid #111;
}

.mem-active {
  color: var(--terminal-green);
  background: rgba(0,255,65,0.1);
}

.cpu-controls {
  display: flex;
  gap: 6px;
  margin-bottom: 8px;
}

.cpu-controls button {
  flex: 1;
  padding: 5px;
  font-family: 'Press Start 2P', cursive;
  font-size: 8px;
  background: #0a120a;
  border: 1px solid var(--pcb-green);
  color: var(--terminal-green);
  cursor: pointer;
  border-radius: 3px;
  transition: all 0.15s;
}

.cpu-controls button:hover {
  background: var(--pcb-green);
}

.cpu-stats {
  display: flex;
  justify-content: space-around;
  font-size: 14px;
  color: var(--text-dim);
}

.cpu-stats b {
  color: var(--oled-cyan);
}

footer {
  text-align: center;
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid #1a2a1a;
  width: 100%;
}

footer p {
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 6px;
}

footer a {
  color: var(--terminal-green);
  text-decoration: none;
  font-family: 'Press Start 2P', cursive;
  font-size: 10px;
  transition: text-shadow 0.3s;
}

footer a:hover {
  text-shadow: 0 0 10px var(--terminal-green);
}

@media (max-width: 600px) {
  header h1 { font-size: 13px; }
  .subtitle { font-size: 12px; }
  #status-bar { gap: 8px; font-size: 12px; }
  .status-item { font-size: 12px; padding: 2px 6px; }
  .upload-inner p { font-size: 14px; }
  #keyboard-hint { display: none; }
  #buzzer-controls { max-width: 100%; }
  #cpu-panel { max-width: 100%; }
  #registers-grid { grid-template-columns: repeat(3, 1fr); }
}