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

:root {
  --bg:      #0f1117;
  --surface: #1a1d2e;
  --surface2:#252840;
  --border:  #2e3250;
  --accent:  #6c63ff;
  --accent2: #ff6584;
  --green:   #43e97b;
  --red:     #ff4d6d;
  --text:    #e8eaf6;
  --text2:   #9294a8;
  --radius:  12px;
  --shadow:  0 4px 24px rgba(0,0,0,0.4);

  --l1: #f59e0b;
  --l2: #06b6d4;
  --l3: #43e97b;
  --l4: #6c63ff;
  --l5: #ff6584;
  --l6: #98d843;

  --sig-high:    #43e97b;
  --sig-low:     #ff4d6d;
  --sig-unknown: #9294a8;
  --electron:    #60a5fa;
  --hole:        #f87171;
  --current:     #fbbf24;
}

html, body { height: 100%; overflow: hidden; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  line-height: 1.5;
}

/* ── App Shell ── */
#app {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

/* ── Header ── */
#main-header {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 24px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow);
}
#main-header h1 {
  font-size: 1.4rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.subtitle {
  color: var(--text2);
  font-size: 0.78rem;
  margin-top: 1px;
}
.back-link {
  color: var(--text2);
  text-decoration: none;
  font-size: 0.85rem;
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  transition: all 150ms;
}
.back-link:hover { color: var(--text); border-color: var(--accent); }

/* ── Layer Nav ── */
#layer-nav {
  flex-shrink: 0;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 20px;
}
.layer-nav-track {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 8px 0;
  overflow-x: auto;
  scrollbar-width: none;
}
.layer-nav-track::-webkit-scrollbar { display: none; }
.layer-nav-arrow {
  color: var(--border);
  font-size: 0.9rem;
  padding: 0 2px;
  flex-shrink: 0;
}
.layer-nav-btn {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 7px 14px;
  border-radius: 8px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text2);
  cursor: pointer;
  white-space: nowrap;
  font-size: 0.82rem;
  font-weight: 600;
  transition: all 150ms;
  flex-shrink: 0;
}
.layer-nav-btn:hover { background: var(--surface2); color: var(--text); }
.layer-nav-btn.active { background: var(--surface2); border-color: var(--border); color: var(--text); }
.layer-nav-btn[data-layer="1"].active { color: var(--l1); border-color: var(--l1); }
.layer-nav-btn[data-layer="2"].active { color: var(--l2); border-color: var(--l2); }
.layer-nav-btn[data-layer="3"].active { color: var(--l3); border-color: var(--l3); }
.layer-nav-btn[data-layer="4"].active { color: var(--l4); border-color: var(--l4); }
.layer-nav-btn[data-layer="5"].active { color: var(--l5); border-color: var(--l5); }
.layer-nav-btn[data-layer="6"].active { color: var(--l6); border-color: var(--l6); }
.layer-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 20px; height: 20px;
  border-radius: 50%;
  background: var(--surface2);
  font-size: 0.72rem;
  font-weight: 700;
  flex-shrink: 0;
}

/* ── Workspace ── */
#workspace {
  flex: 1;
  overflow: hidden;
  position: relative;
}
.layer-section {
  display: none;
  width: 100%;
  height: 100%;
}
.layer-section.active {
  display: flex;
  flex-direction: column;
  animation: layerEnter 280ms ease;
}
@keyframes layerEnter {
  from { opacity: 0; transform: scale(0.97) translateY(4px); }
  to   { opacity: 1; transform: scale(1)    translateY(0);   }
}

/* ── Layer Layout ── */
.layer-layout {
  display: grid;
  grid-template-columns: 1fr 270px;
  gap: 14px;
  padding: 14px;
  height: 100%;
  overflow: hidden;
}
.layer-canvas-area {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.canvas-label {
  padding: 10px 14px 8px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text2);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.canvas-label code {
  background: var(--surface2);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.85em;
  color: var(--accent);
}
.layer-canvas-area canvas,
.layer-canvas-area svg {
  flex: 1;
  min-height: 0;
  display: block;
}
.layer-canvas-area canvas { width: 100% !important; }

.layer-controls-area {
  display: flex;
  flex-direction: column;
  gap: 10px;
  overflow-y: auto;
  min-height: 0;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}

/* ── Control Cards ── */
.control-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  flex-shrink: 0;
}
.control-card h3 {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text2);
  margin-bottom: 10px;
}
.control-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 5px 0;
  border-bottom: 1px solid var(--border);
}
.control-row:last-child { border-bottom: none; }
.control-label {
  font-size: 0.82rem;
  color: var(--text2);
  flex-shrink: 0;
}

/* ── Buttons ── */
.btn-group {
  display: flex;
  gap: 4px;
}
.btn-group.vertical { flex-direction: column; width: 100%; }

.input-btn, .gate-btn, .op-btn {
  padding: 5px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--text2);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 150ms;
}
.input-btn:hover, .gate-btn:hover, .op-btn:hover { color: var(--text); border-color: var(--accent); }
.input-btn.active, .gate-btn.active, .op-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.op-btn { width: 100%; text-align: center; padding: 7px; }

.toggle-btn {
  padding: 5px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--text2);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 150ms;
}
.toggle-btn.active { background: #43e97b22; border-color: var(--green); color: var(--green); }

.action-btn {
  width: 100%;
  padding: 8px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--text);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 150ms;
}
.action-btn:hover { border-color: var(--accent); color: var(--accent); }
.primary-btn {
  background: linear-gradient(135deg, var(--accent), #8b5cf6);
  border-color: transparent;
  color: #fff;
}
.primary-btn:hover { opacity: 0.9; color: #fff; }

.status-badge {
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}
.status-badge.on  { background: #43e97b22; color: var(--green); border: 1px solid var(--green); }
.status-badge.off { background: #ff4d6d22; color: var(--red);   border: 1px solid var(--red);   }

.val-badge {
  padding: 3px 10px;
  border-radius: 6px;
  background: var(--surface2);
  color: var(--accent);
  font-size: 0.82rem;
  font-family: 'Consolas', monospace;
  font-weight: 700;
  border: 1px solid var(--border);
}

/* ── Slider ── */
.slider {
  flex: 1;
  height: 4px;
  appearance: none;
  background: var(--surface2);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}
.slider::-webkit-slider-thumb {
  appearance: none;
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: 2px solid var(--bg);
}
.slider::-moz-range-thumb {
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: 2px solid var(--bg);
}

/* ── Number input ── */
.num-input {
  width: 60px;
  padding: 5px 8px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--text);
  font-size: 0.85rem;
  text-align: center;
}
.num-input:focus { outline: none; border-color: var(--accent); }

/* ── Legend ── */
.legend-row {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--text2);
  padding: 3px 0;
}
.legend-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* ── Sublayer Tabs ── */
.sublayer-tabs {
  display: flex;
  gap: 4px;
  padding: 10px 12px 0;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.sublayer-tab {
  padding: 6px 16px;
  border-radius: 6px 6px 0 0;
  border: 1px solid var(--border);
  border-bottom: none;
  background: var(--surface2);
  color: var(--text2);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 150ms;
  margin-bottom: -1px;
}
.sublayer-tab:hover { color: var(--text); }
.sublayer-tab.active {
  background: var(--surface);
  color: var(--text);
  border-bottom-color: var(--surface);
}

/* ── Embedded Truth Table ── */
.embedded-truth-table {
  padding: 10px 14px;
  flex-shrink: 0;
  overflow-x: auto;
  border-top: 1px solid var(--border);
}
.embedded-truth-table table {
  border-collapse: collapse;
  font-size: 0.82rem;
  font-family: 'Consolas', monospace;
}
.embedded-truth-table th {
  padding: 4px 14px;
  background: var(--surface2);
  color: var(--text2);
  font-weight: 700;
  text-transform: uppercase;
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  border: 1px solid var(--border);
}
.embedded-truth-table td {
  padding: 5px 14px;
  text-align: center;
  border: 1px solid var(--border);
  color: var(--text2);
  transition: all 200ms;
}
.embedded-truth-table tr.active-row td {
  color: var(--text);
  background: var(--surface2);
}
.embedded-truth-table td.val-1 { color: var(--green); font-weight: 700; }
.embedded-truth-table td.val-0 { color: var(--red); }

/* ── Output Display ── */
.output-display {
  font-family: 'Consolas', monospace;
  font-size: 0.9rem;
}
.output-line {
  display: flex;
  justify-content: space-between;
  padding: 5px 0;
  border-bottom: 1px solid var(--border);
}
.output-line:last-child { border-bottom: none; }
.output-key { color: var(--text2); font-size: 0.82rem; }
.output-val { font-weight: 700; }
.output-val.high { color: var(--green); }
.output-val.low  { color: var(--red);   }

/* ── Info Body ── */
.info-body {
  font-size: 0.82rem;
  color: var(--text2);
  line-height: 1.6;
}

/* ── Pipeline Track ── */
.pipeline-track {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.pipeline-stage {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 7px 18px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface2);
  transition: all 250ms;
  cursor: default;
}
.pipeline-stage.active {
  border-color: var(--accent);
  background: rgba(108,99,255,0.15);
  box-shadow: 0 0 12px rgba(108,99,255,0.3);
}
.ps-num { font-size: 0.68rem; color: var(--text2); }
.ps-label { font-size: 0.82rem; font-weight: 700; color: var(--text); }
.pipeline-stage.active .ps-label { color: var(--accent); }
.pipeline-arrow { color: var(--border); font-size: 1rem; }

/* ── Step Footer ── */
#step-footer {
  flex-shrink: 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 10px 20px;
}
.step-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}
.step-btn {
  padding: 7px 16px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--text);
  font-weight: 600;
  font-size: 0.82rem;
  cursor: pointer;
  transition: all 150ms;
  white-space: nowrap;
}
.step-btn:hover { border-color: var(--accent); color: var(--accent); }
.step-btn:disabled { opacity: 0.35; cursor: not-allowed; }
.step-btn:disabled:hover { border-color: var(--border); color: var(--text); }
.step-btn--primary {
  background: linear-gradient(135deg, var(--accent), #8b5cf6);
  border-color: transparent;
  color: #fff;
}
.step-btn--primary:hover { opacity: 0.9; color: #fff; }
.step-btn--layer {
  font-size: 0.75rem;
  padding: 7px 12px;
  color: var(--text2);
}
.step-btn--play { border-color: var(--green); color: var(--green); }
.step-btn--play.playing { background: #43e97b22; }
.step-indicator {
  font-family: 'Consolas', monospace;
  font-size: 0.88rem;
  color: var(--text2);
  min-width: 52px;
  text-align: center;
  flex-shrink: 0;
}
.step-sep { margin: 0 2px; }
#step-current { color: var(--text); font-weight: 700; }

.info-panel {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 9px 13px;
  min-height: 44px;
}
.info-panel-icon {
  color: var(--accent);
  font-size: 1rem;
  flex-shrink: 0;
  margin-top: 1px;
}
.info-text {
  font-size: 0.84rem;
  color: var(--text);
  line-height: 1.55;
}

/* ── Transition Overlay ── */
.transition-overlay {
  position: fixed;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: rgba(15,17,23,0.92);
  z-index: 9999;
  backdrop-filter: blur(10px);
}
.transition-overlay.hidden { display: none; }
.transition-zoom-ring {
  width: 100px; height: 100px;
  border-radius: 50%;
  border: 3px solid var(--accent);
  animation: zoomRing 0.55s ease forwards;
}
@keyframes zoomRing {
  from { transform: scale(0.2); opacity: 1; }
  to   { transform: scale(5);   opacity: 0; }
}
.transition-label {
  margin-top: 28px;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text);
  animation: fadeUp 0.35s 0.1s both;
}
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0);    }
}

/* ── SVG Wire Animations ── */
.wire-animated {
  stroke-dasharray: 6 10;
  animation: dashFlow 0.7s linear infinite;
}
@keyframes dashFlow {
  to { stroke-dashoffset: -16; }
}
.element-glow {
  filter: drop-shadow(0 0 5px currentColor);
}
.element-pulse {
  animation: elPulse 1s ease infinite;
}
@keyframes elPulse {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0.55; }
}

/* ── Register Display ── */
.reg-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 0;
  border-bottom: 1px solid var(--border);
  gap: 8px;
}
.reg-row:last-child { border-bottom: none; }
.reg-name {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text2);
  width: 28px;
  flex-shrink: 0;
}
.reg-bits {
  display: flex;
  gap: 3px;
}
.reg-bit {
  width: 22px; height: 22px;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: var(--surface2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.78rem;
  font-weight: 700;
  font-family: 'Consolas', monospace;
  cursor: pointer;
  transition: all 150ms;
  color: var(--text2);
}
.reg-bit.b1 { color: var(--green); background: #43e97b15; border-color: #43e97b44; }
.reg-bit:hover { border-color: var(--accent); color: var(--accent); }
.reg-val {
  font-size: 0.75rem;
  color: var(--text2);
  font-family: 'Consolas', monospace;
  width: 28px;
  text-align: right;
}

/* ── Responsive ── */
@media (max-width: 900px) {
  .layer-layout {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr auto;
  }
  .layer-controls-area {
    flex-direction: row;
    overflow-x: auto;
    overflow-y: visible;
    max-height: 160px;
  }
  .control-card { min-width: 200px; }
}
@media (max-width: 600px) {
  .layer-label { display: none; }
  .step-btn--layer { display: none; }
  #main-header h1 { font-size: 1.1rem; }
  .layer-layout { gap: 8px; padding: 8px; }
}