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

:root {
  --bg: #0a0a14;
  --panel: #0d0d12;
  --panel-border: #1a1a2a;
  --cga-green: #33ff33;
  --cga-amber: #ffb000;
  --cga-dim: #0a3a0a;
  --ibm-blue: #0062ff;
  --red: #ff3333;
  --yellow: #e8c500;
  --text: #c0c0c0;
  --text-dim: #606070;
  --bezel-outer: #2a2a2a;
  --bezel-inner: #1a1a1a;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'IBM Plex Mono', 'Consolas', 'Courier New', monospace;
  min-height: 100vh;
  overflow-x: hidden;
}

#app {
  max-width: 1400px;
  margin: 0 auto;
  padding: 12px;
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: linear-gradient(180deg, #141420, #0d0d18);
  border: 1px solid var(--panel-border);
  border-radius: 6px;
  margin-bottom: 10px;
}

.header-left { display: flex; align-items: center; gap: 14px; }

.header-title {
  font-size: 18px;
  font-weight: 700;
  color: #e0e0e0;
  letter-spacing: -0.5px;
}

.header-sub {
  font-size: 11px;
  color: var(--text-dim);
  font-weight: 400;
}

.led {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}

.led-green {
  background: var(--cga-green);
  box-shadow: 0 0 6px var(--cga-green), 0 0 12px rgba(51,255,51,0.3);
}

.led-red {
  background: var(--red);
  box-shadow: 0 0 6px var(--red), 0 0 12px rgba(255,51,51,0.3);
}

.led-off {
  background: #222;
  box-shadow: none;
}

.led-amber {
  background: var(--cga-amber);
  box-shadow: 0 0 6px var(--cga-amber);
}

@keyframes blink { 0%,100% { opacity: 1; } 50% { opacity: 0.3; } }
.led-blink { animation: blink 1s infinite; }

.status-bar {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 11px;
  color: var(--text-dim);
}

.status-item {
  display: flex;
  align-items: center;
  gap: 5px;
}

.status-value {
  color: var(--cga-green);
  font-weight: 600;
}

.main-layout {
  display: grid;
  grid-template-columns: 220px 1fr 240px;
  grid-template-rows: auto auto;
  gap: 10px;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 5px;
  padding: 10px;
}

.panel-title {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 8px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--panel-border);
}

/* Left sidebar - floppy */
.sidebar-left { grid-column: 1; grid-row: 1 / 3; }

.floppy-slot {
  background: #060608;
  border: 1px solid #222;
  border-radius: 3px;
  padding: 10px;
  margin-bottom: 10px;
  position: relative;
}

.floppy-slot-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--cga-green);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.floppy-opening {
  width: 100%;
  height: 4px;
  background: #000;
  border: 1px solid #1a1a1a;
  border-radius: 2px;
  margin: 8px 0;
}

.floppy-info {
  font-size: 10px;
  color: var(--text-dim);
  margin-top: 4px;
  word-break: break-all;
}

.btn {
  font-family: inherit;
  font-size: 11px;
  font-weight: 600;
  border: none;
  border-radius: 3px;
  padding: 5px 10px;
  cursor: pointer;
  transition: all 0.15s;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.btn:hover { filter: brightness(1.2); }
.btn:active { transform: scale(0.97); }

.btn-insert {
  background: var(--ibm-blue);
  color: #fff;
  width: 100%;
  margin-top: 6px;
}

.btn-eject {
  background: #333;
  color: #aaa;
  width: 100%;
  margin-top: 4px;
}

.btn-power-on { background: var(--cga-green); color: #000; }
.btn-power-off { background: var(--red); color: #fff; }
.btn-reset { background: var(--yellow); color: #000; }
.btn-pause { background: var(--ibm-blue); color: #fff; }
.btn-step { background: #555; color: #ddd; }

/* CGA display area */
.display-area { grid-column: 2; grid-row: 1; }

.crt-bezel {
  background: linear-gradient(145deg, #3d3d3d, #222);
  border-radius: 12px;
  padding: 14px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.5), inset 0 1px 0 rgba(255,255,255,0.05);
}

.crt-inner {
  background: #000;
  border-radius: 8px;
  padding: 6px;
  box-shadow: inset 0 0 30px rgba(0,0,0,0.8), inset 0 0 6px rgba(0,50,0,0.3);
  position: relative;
  overflow: hidden;
}

.crt-inner::after {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0,0,0,0.15) 2px,
    rgba(0,0,0,0.15) 4px
  );
  pointer-events: none;
  z-index: 2;
}

#cga-canvas {
  display: block;
  width: 100%;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  border-radius: 4px;
  position: relative;
  z-index: 1;
}

.controls-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 10px;
  flex-wrap: wrap;
}

.speed-control {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
}

.speed-control label {
  font-size: 10px;
  color: var(--text-dim);
}

.speed-control input[type=range] {
  width: 100px;
  accent-color: var(--ibm-blue);
}

/* Right sidebar - registers */
.sidebar-right { grid-column: 3; grid-row: 1 / 3; }

.reg-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2px;
}

.reg-item {
  display: flex;
  justify-content: space-between;
  padding: 2px 4px;
  font-size: 12px;
  border-radius: 2px;
}

.reg-item:hover { background: rgba(255,255,255,0.03); }

.reg-name {
  color: var(--text-dim);
  font-weight: 500;
}

.reg-val {
  color: var(--cga-green);
  font-weight: 600;
}

.flags-row {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
  margin-top: 6px;
}

.flag-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  font-size: 9px;
}

.flag-label { color: var(--text-dim); }

.flag-led {
  width: 6px;
  height: 6px;
  border-radius: 50%;
}

.flag-set {
  background: var(--cga-green);
  box-shadow: 0 0 4px var(--cga-green);
}

.flag-clear {
  background: #1a1a1a;
}

.section-sep {
  font-size: 10px;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin: 8px 0 4px;
  padding-top: 6px;
  border-top: 1px solid var(--panel-border);
}

/* Bottom panels */
.bottom-area {
  grid-column: 1 / 4;
  grid-row: 2;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.disasm-line {
  font-size: 11px;
  padding: 1px 4px;
  border-radius: 2px;
  display: flex;
  gap: 10px;
  white-space: nowrap;
}

.disasm-current {
  background: rgba(255,176,0,0.15);
  color: var(--cga-amber);
}

.disasm-addr { color: var(--text-dim); min-width: 80px; }
.disasm-bytes { color: #666; min-width: 90px; }
.disasm-mnem { color: var(--cga-green); font-weight: 600; }

.mem-viewer {
  font-size: 11px;
  max-height: 200px;
  overflow-y: auto;
}

.mem-line {
  display: flex;
  gap: 6px;
  padding: 1px 0;
}

.mem-addr { color: var(--text-dim); min-width: 55px; }
.mem-hex { color: var(--cga-green); }
.mem-ascii { color: #666; margin-left: 8px; }

.mem-input-row {
  display: flex;
  gap: 6px;
  margin-bottom: 6px;
}

.mem-input {
  background: #0a0a0a;
  border: 1px solid #222;
  color: var(--cga-green);
  font-family: inherit;
  font-size: 11px;
  padding: 3px 6px;
  border-radius: 3px;
  width: 100px;
}

/* Devices panel */
.device-badge {
  display: inline-block;
  background: #0a1a0a;
  color: var(--cga-green);
  font-size: 10px;
  padding: 2px 6px;
  border-radius: 2px;
  border: 1px solid #1a3a1a;
  margin: 2px;
}

.printer-output {
  background: #f5f0e0;
  color: #333;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  padding: 8px;
  border-radius: 3px;
  min-height: 60px;
  max-height: 120px;
  overflow-y: auto;
  border-top: 4px solid transparent;
  border-image: repeating-linear-gradient(90deg, #ccc 0px, #ccc 4px, transparent 4px, transparent 8px) 4;
}

.collapsible-header {
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.collapsible-header:hover { color: var(--cga-green); }

.collapse-arrow {
  font-size: 10px;
  transition: transform 0.2s;
}

.collapse-arrow.open { transform: rotate(90deg); }

.tab-bar {
  display: flex;
  gap: 2px;
  margin-bottom: 8px;
}

.tab-btn {
  font-family: inherit;
  font-size: 10px;
  padding: 4px 10px;
  background: #111;
  border: 1px solid var(--panel-border);
  color: var(--text-dim);
  cursor: pointer;
  border-radius: 3px 3px 0 0;
  transition: all 0.15s;
}

.tab-btn.active {
  background: var(--panel);
  color: var(--cga-green);
  border-bottom-color: var(--panel);
}

.footer {
  text-align: center;
  padding: 16px;
  font-size: 10px;
  color: var(--text-dim);
  margin-top: 10px;
  border-top: 1px solid var(--panel-border);
}

.footer a {
  color: var(--ibm-blue);
  text-decoration: none;
}

.footer a:hover { text-decoration: underline; }

/* Drop zone */
.drop-zone {
  border: 1px dashed #333;
  border-radius: 3px;
  padding: 8px;
  text-align: center;
  font-size: 10px;
  color: var(--text-dim);
  transition: all 0.2s;
  cursor: pointer;
}

.drop-zone:hover, .drop-zone.dragover {
  border-color: var(--ibm-blue);
  color: var(--ibm-blue);
  background: rgba(0,98,255,0.05);
}

/* Scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--panel); }
::-webkit-scrollbar-thumb { background: #333; border-radius: 3px; }

@media (max-width: 1100px) {
  .main-layout {
    grid-template-columns: 1fr;
    grid-template-rows: auto;
  }
  .sidebar-left, .sidebar-right { grid-column: 1; grid-row: auto; }
  .display-area { grid-column: 1; }
  .bottom-area { grid-column: 1; grid-template-columns: 1fr; }
}