/* APUE Simulator */
:root,
:root[data-theme="dark"] {
  --bg: #0d1117;
  --surface: #161b22;
  --border: #30363d;
  --text: #e6edf3;
  --text-dim: #7d8590;
  --accent: #e94560;
  --accent2: #00b4d8;
  --green: #06d6a0;
  --yellow: #ffd166;
  --purple: #8338ec;
  --font-mono: 'SF Mono', 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
  --font-sans: 'Inter', -apple-system, 'Segoe UI', sans-serif;
}

:root[data-theme="light"] {
  --bg: #f6f8fa;
  --surface: #ffffff;
  --border: #d0d7de;
  --text: #1f2328;
  --text-dim: #656d76;
  --accent: #cf222e;
  --accent2: #0969da;
  --green: #1a7f37;
  --yellow: #9a6700;
  --purple: #6639a6;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
header {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  flex-shrink: 0;
}

header h1 {
  font-size: 16px;
  font-weight: 700;
  color: var(--accent);
  font-family: var(--font-mono);
  white-space: nowrap;
}

.progress-indicator {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-dim);
  background: var(--bg);
  padding: 2px 8px;
  border-radius: 4px;
  border: 1px solid var(--border);
}

.visited-check {
  color: var(--green);
  font-size: 10px;
}

header .subtitle {
  font-size: 12px;
  color: var(--text-dim);
}

header .spacer { flex: 1; }

header button {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 13px;
  cursor: pointer;
}

header button:hover {
  background: var(--border);
  color: var(--text);
}

/* Layout */
.app-layout {
  flex: 1;
  display: flex;
  overflow: hidden;
}

/* Left sidebar */
.module-sidebar {
  width: 200px;
  min-width: 200px;
  background: var(--surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 8px 0;
  flex-shrink: 0;
}

.module-sidebar.collapsed {
  width: 0; min-width: 0; padding: 0; overflow: hidden;
}

nav { display: flex; flex-direction: column; }

.nav-group { margin-bottom: 4px; }

.nav-group-title {
  padding: 6px 14px;
  font-size: 10px;
  font-weight: 700;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  cursor: pointer;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-group-title::before {
  content: '\25BE';
  font-size: 8px;
  transition: transform 0.15s;
}

.nav-group.closed .nav-group-title::before {
  transform: rotate(-90deg);
}

.nav-group.closed > button { display: none; }

nav button {
  display: block;
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  border-left: 3px solid transparent;
  color: var(--text-dim);
  padding: 5px 14px 5px 18px;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.12s;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

nav button:hover { background: var(--bg); color: var(--text); }

nav button.active {
  background: var(--accent)18;
  border-left-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}

/* Main content */
main {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 16px 20px;
  gap: 12px;
  overflow-y: auto;
}

/* Scenario selector */
.scenario-selector {
  display: flex;
  align-items: center;
  gap: 10px;
}

.scenario-selector label {
  font-size: 12px;
  color: var(--text-dim);
  font-weight: 600;
}

.scenario-selector select {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  cursor: pointer;
  flex: 1;
  max-width: 400px;
}

/* Split pane: code + kernel state */
.split-pane {
  display: flex;
  gap: 16px;
  flex: 1;
  min-height: 0;
}

/* Code panel (left) */
.code-panel {
  width: 340px;
  min-width: 280px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.code-panel-header {
  padding: 8px 14px;
  font-size: 11px;
  font-weight: 600;
  color: var(--text-dim);
  border-bottom: 1px solid var(--border);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.code-lines {
  flex: 1;
  overflow-y: auto;
  padding: 8px 0;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
}

.code-line {
  padding: 2px 14px;
  white-space: pre-wrap;
  color: var(--text-dim);
  transition: all 0.15s;
  cursor: pointer;
  border-left: 3px solid transparent;
}

.code-line:hover {
  background: var(--bg);
}

.code-line.active {
  background: var(--accent2)18;
  color: var(--text);
  border-left-color: var(--accent2);
  font-weight: 500;
}

.code-line.past {
  color: var(--text);
  opacity: 0.7;
}

/* Kernel state panel (right) */
.kernel-panel {
  flex: 1;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: auto;
  padding: 16px;
  position: relative;
}

.kernel-panel-header {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
}

/* 3-column kernel diagram */
.kernel-diagram {
  display: flex;
  gap: 24px;
  align-items: flex-start;
  min-height: 200px;
  position: relative;
  z-index: 1;
}

.diagram-col {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
}

.col-fd { flex: 1.2; }
.col-fte { flex: 1.4; }
.col-vnode { flex: 1; }

.col-title {
  font-size: 10px;
  font-weight: 700;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 4px;
}

/* SVG arrow overlay */
.arrow-svg {
  position: absolute;
  top: 0;
  left: 0;
  pointer-events: none;
  z-index: 0;
}

/* Process box (fd column) */
.process-box {
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 8px;
}

.process-header {
  padding: 5px 10px;
  font-size: 11px;
  font-weight: 600;
  font-family: var(--font-mono);
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.pid-label {
  font-size: 10px;
  color: var(--text-dim);
  font-weight: 400;
}

/* fd row inside process box */
.fd-row {
  display: flex;
  align-items: center;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  border-bottom: 1px solid var(--border)33;
  transition: background 0.3s;
  gap: 8px;
}

.fd-row:last-child { border-bottom: none; }

.fd-row.added { background: var(--green)18; }
.fd-row.changed { background: var(--yellow)18; }

.fd-num {
  min-width: 60px;
  color: var(--text);
  font-weight: 500;
}

.fd-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent2);
  flex-shrink: 0;
  margin-left: auto;
}

/* FTE cards (file table column) */
.fte-card {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 0;
  font-family: var(--font-mono);
  font-size: 11px;
  transition: all 0.3s;
  position: relative;
}

.fte-card.anim-appear {
  border-color: var(--green);
  box-shadow: 0 0 8px var(--green)44;
}

.fte-card.anim-pulse {
  border-color: var(--yellow);
  box-shadow: 0 0 8px var(--yellow)44;
}

.fte-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.fte-card .fte-dot:first-child {
  background: var(--accent2);
  margin-left: 6px;
}

.fte-card .fte-dot:last-child {
  background: var(--purple);
  margin-right: 6px;
}

.fte-body {
  flex: 1;
  min-width: 0;
}

.fte-id {
  font-weight: 700;
  color: var(--accent2);
  font-size: 11px;
}

.fte-field {
  color: var(--text-dim);
  font-size: 10px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.fte-field span { color: var(--text); }

.fte-field.val-changed { color: var(--yellow); }

.diff-from {
  color: var(--text-dim);
  font-size: 9px;
  opacity: 0.7;
}

/* Vnode cards */
.vnode-card {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 0;
  font-family: var(--font-mono);
  font-size: 11px;
  position: relative;
}

.vnode-card.anim-appear {
  border-color: var(--green);
  box-shadow: 0 0 8px var(--green)44;
}

.vnode-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--purple);
  flex-shrink: 0;
  margin-left: 6px;
}

.vnode-body {
  flex: 1;
  min-width: 0;
  padding-right: 10px;
}

.vnode-path {
  font-weight: 700;
  color: var(--purple);
  font-size: 11px;
}

/* Animations */
@keyframes appear {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}

@keyframes pulse {
  0% { box-shadow: 0 0 0 0 var(--yellow)66; }
  50% { box-shadow: 0 0 12px 2px var(--yellow)44; }
  100% { box-shadow: 0 0 8px 0 var(--yellow)22; }
}

.anim-appear { animation: appear 0.35s ease-out; }
.anim-pulse { animation: pulse 0.6s ease-out; }

/* Figure badge */
.figure-badge {
  display: inline-block;
  background: var(--accent)22;
  color: var(--accent);
  border: 1px solid var(--accent)44;
  border-radius: 4px;
  padding: 2px 8px;
  font-size: 11px;
  font-family: var(--font-mono);
  font-weight: 600;
  margin-left: 8px;
}

/* Keyboard hint */
.key-hint {
  font-size: 11px;
  color: var(--text-dim);
  margin-left: auto;
  font-family: var(--font-mono);
  opacity: 0.6;
}

/* Syntax highlighting */
.syn-comment { color: var(--text-dim); font-style: italic; }
.syn-string { color: var(--green); }
.syn-type { color: var(--accent2); }
.syn-syscall { color: var(--accent); font-weight: 600; }
.syn-const { color: var(--yellow); }
.syn-num { color: var(--purple); }
.syn-tag {
  color: var(--green);
  font-weight: 700;
  font-size: 10px;
  background: var(--green)18;
  padding: 1px 4px;
  border-radius: 3px;
  border: 1px solid var(--green)33;
  margin-right: 4px;
}

/* Code line number */
.line-num {
  display: inline-block;
  width: 22px;
  text-align: right;
  color: var(--text-dim);
  opacity: 0.4;
  font-size: 10px;
  margin-right: 10px;
  user-select: none;
}

.code-line.active .line-num { opacity: 0.8; }

/* Process tree */
.process-tree {
  margin-bottom: 12px;
}

.ptree-container {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: flex-start;
}

.ptree-node {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 14px;
  min-width: 120px;
  font-family: var(--font-mono);
  font-size: 11px;
  display: flex;
  flex-direction: column;
  gap: 3px;
  transition: all 0.3s;
}

.ptree-node.running {
  border-color: var(--green)88;
}

.ptree-node.zombie {
  border-color: var(--accent)88;
  opacity: 0.7;
  background: var(--accent)08;
}

.ptree-pid {
  font-weight: 700;
  color: var(--accent2);
  font-size: 12px;
}

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

.ptree-program {
  color: var(--text-dim);
  font-size: 10px;
}

.ptree-state-badge {
  display: inline-block;
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 9px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  width: fit-content;
}

.ptree-state-badge.running {
  background: var(--green)22;
  color: var(--green);
  border: 1px solid var(--green)44;
}

.ptree-state-badge.zombie {
  background: var(--accent)22;
  color: var(--accent);
  border: 1px solid var(--accent)44;
}

.ptree-exit {
  color: var(--accent);
  font-size: 10px;
}

.ptree-fds {
  color: var(--text-dim);
  font-size: 10px;
}

/* Related module links */
.related-links {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
  padding: 6px 0;
  margin-top: 4px;
}

.related-label {
  font-size: 10px;
  color: var(--text-dim);
  font-weight: 600;
  text-transform: uppercase;
}

.related-btn {
  background: transparent;
  border: 1px dashed var(--accent2)66;
  color: var(--accent2);
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 10px;
  font-family: var(--font-mono);
  cursor: pointer;
  transition: all 0.15s;
}

.related-btn:hover {
  background: var(--accent2)18;
  border-style: solid;
}

/* Deadlock alert */
.deadlock-alert {
  background: var(--accent)22;
  border: 2px solid var(--accent);
  border-radius: 8px;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  color: var(--accent);
  text-align: center;
  margin-bottom: 12px;
}

/* Terminal mode badge */
.term-mode-badge {
  display: inline-block;
  padding: 6px 16px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 12px;
  border: 1px solid currentColor;
}

.term-buffer-section { margin-top: 12px; }

.term-buffer {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text);
  min-height: 28px;
}

.term-read-result {
  background: var(--green)15;
  border: 1px solid var(--green)44;
  border-radius: 4px;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--green);
}

/* PTY diagram */
.pty-diagram {
  display: flex;
  gap: 12px;
  align-items: stretch;
  margin-bottom: 16px;
}

.pty-side {
  flex: 1;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  transition: all 0.3s;
}

.pty-side-label { font-weight: 700; color: var(--accent2); font-size: 13px; margin-bottom: 4px; }
.pty-side-owner { color: var(--text); margin-bottom: 2px; }
.pty-side-fd { color: var(--text-dim); font-size: 10px; }

.pty-middle {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-width: 80px;
  gap: 4px;
}

.pty-arrow-line { font-size: 24px; color: var(--accent2); }

.pty-ld-box {
  background: var(--yellow)15;
  border: 1px solid var(--yellow)44;
  border-radius: 4px;
  padding: 4px 8px;
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--yellow);
  font-weight: 600;
  white-space: nowrap;
}

.pty-ld-flags { font-family: var(--font-mono); font-size: 9px; color: var(--text-dim); white-space: nowrap; }

.pty-flow-section { margin-bottom: 12px; }

.pty-flow-item {
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  border-bottom: 1px solid var(--border)33;
}

.pty-flow-dir { color: var(--accent2); font-weight: 600; min-width: 160px; }
.pty-flow-data { color: var(--green); }

.pty-typescript {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 12px;
  margin-bottom: 12px;
}

.pty-typescript-content {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text);
  margin: 0;
  white-space: pre-wrap;
}

/* Socket diagram */
.socket-diagram {
  display: flex;
  gap: 12px;
  align-items: stretch;
  margin-bottom: 12px;
}

.socket-endpoint {
  flex: 1;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  transition: all 0.3s;
}

.socket-ep-label {
  font-weight: 700;
  font-size: 13px;
  color: var(--text);
  margin-bottom: 6px;
}

.socket-ep-state {
  font-weight: 700;
  font-size: 12px;
  margin: 4px 0;
}

.socket-ep-field {
  color: var(--text-dim);
  font-size: 10px;
}

.socket-ep-field span {
  color: var(--text);
}

.socket-connection {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-width: 40px;
}

.socket-conn-label {
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--text-dim);
  text-transform: uppercase;
  margin-bottom: 4px;
  white-space: nowrap;
}

.socket-conn-line {
  width: 2px;
  height: 40px;
  background: var(--border);
  border-radius: 1px;
  transition: all 0.3s;
}

.socket-conn-line.socket-connected {
  background: var(--green);
  box-shadow: 0 0 8px var(--green)44;
  width: 3px;
}

.socket-timewait {
  background: var(--yellow)11;
  border: 1px solid var(--yellow)44;
  border-radius: 6px;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--yellow);
  margin-bottom: 12px;
}

/* Memory layout */
.mem-layout-container {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.mem-addr-label {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-dim);
  padding: 4px 0;
}

.mem-layout {
  width: 100%;
  max-width: 400px;
  min-height: 400px;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
}

.mem-segment {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  border-bottom: 1px solid var(--border)44;
  transition: all 0.3s;
  min-height: 30px;
}

.mem-segment.mem-changed {
  animation: pulse 0.6s ease-out;
}

.mem-segment.mem-env {
  background: var(--surface);
  border-left: 4px solid var(--text-dim);
  min-height: 0;
  padding: 4px 12px;
}

.mem-seg-label {
  font-weight: 700;
  font-size: 11px;
  margin-bottom: 2px;
}

.mem-seg-items {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.mem-seg-items span {
  font-size: 10px;
  color: var(--text-dim);
}

/* Daemon steps */
.daemon-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 8px;
  margin-bottom: 12px;
}

.daemon-attr {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  transition: all 0.3s;
}

.daemon-attr-changed {
  border-color: var(--green)88;
  box-shadow: 0 0 8px var(--green)22;
}

.daemon-attr-label {
  font-size: 9px;
  color: var(--text-dim);
  text-transform: uppercase;
  font-weight: 700;
  letter-spacing: 0.5px;
  margin-bottom: 2px;
}

.daemon-attr-value {
  color: var(--text);
  font-weight: 500;
  word-break: break-all;
}

.daemon-status {
  background: var(--accent2)15;
  border: 1px solid var(--accent2)44;
  border-radius: 6px;
  padding: 8px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  color: var(--accent2);
  text-align: center;
  margin-bottom: 12px;
}

.daemon-fds {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.daemon-fd {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-dim);
  padding: 2px 8px;
  background: var(--bg);
  border-radius: 3px;
}

/* Thread sync */
.thread-lanes {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.thread-lane {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 14px;
  min-width: 140px;
  flex: 1;
  font-family: var(--font-mono);
  font-size: 11px;
  transition: all 0.3s;
}

.thread-lane.thr-running { border-color: var(--green)66; }
.thread-lane.thr-blocked { border-color: var(--yellow)66; background: var(--yellow)08; }
.thread-lane.thr-terminated { border-color: var(--accent)66; opacity: 0.5; }

.thr-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4px;
}

.thr-name { font-weight: 700; color: var(--text); }

.thr-state-badge {
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 9px;
  font-weight: 700;
  text-transform: uppercase;
}

.thr-state-badge.thr-running { background: var(--green)22; color: var(--green); }
.thr-state-badge.thr-blocked { background: var(--yellow)22; color: var(--yellow); }
.thr-state-badge.thr-terminated { background: var(--accent)22; color: var(--accent); }

.thr-blocked-on {
  font-size: 10px;
  color: var(--yellow);
  margin-top: 2px;
}

/* Sync objects */
.sync-objects {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.sync-obj {
  display: flex;
  gap: 8px;
  align-items: flex-start;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  min-width: 150px;
}

.sync-icon { font-size: 18px; }

.sync-name { font-weight: 700; color: var(--accent2); margin-bottom: 2px; }

.sync-status { font-size: 10px; }
.sync-locked { color: var(--accent); font-weight: 600; }
.sync-shared { color: var(--accent2); font-weight: 600; }
.sync-free { color: var(--text-dim); }

.sync-wait { font-size: 10px; color: var(--yellow); margin-top: 2px; }

/* Session / Process Group diagram */
.session-box {
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: 10px;
  padding: 14px;
}

.session-header {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

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

.pg-box {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  margin-bottom: 10px;
  transition: all 0.3s;
}

.pg-foreground {
  border-color: var(--green)88;
  background: var(--green)08;
}

.pg-background {
  border-color: var(--border);
  background: transparent;
}

.pg-header {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
}

.pg-label {
  font-weight: 700;
  color: var(--text);
}

.pg-badge {
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 9px;
  font-weight: 700;
  text-transform: uppercase;
}

.pg-fg-badge {
  background: var(--green)22;
  color: var(--green);
  border: 1px solid var(--green)44;
}

.pg-bg-badge {
  background: var(--border)44;
  color: var(--text-dim);
  border: 1px solid var(--border);
}

.pg-processes {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.session-proc {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 12px;
  min-width: 100px;
  font-family: var(--font-mono);
  font-size: 11px;
  transition: all 0.3s;
}

.session-proc.proc-running { border-color: var(--green)66; }
.session-proc.proc-stopped { border-color: var(--yellow)66; opacity: 0.7; background: var(--yellow)08; }
.session-proc.proc-zombie { border-color: var(--accent)66; opacity: 0.5; background: var(--accent)08; }

.session-proc-name {
  font-weight: 600;
  color: var(--text);
  margin-bottom: 2px;
}

.session-proc-pid {
  color: var(--accent2);
  font-size: 10px;
}

.session-proc-state {
  font-size: 9px;
  font-weight: 700;
  text-transform: uppercase;
  margin-top: 2px;
}

.session-proc-state.proc-running { color: var(--green); }
.session-proc-state.proc-stopped { color: var(--yellow); }
.session-proc-state.proc-zombie { color: var(--accent); }

.session-proc-leader {
  font-size: 9px;
  color: var(--text-dim);
  font-style: italic;
  margin-top: 1px;
}

/* Record lock diagram */
.lock-diagram {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  margin-bottom: 12px;
}

.lock-ruler {
  position: relative;
  height: 20px;
  margin-left: 60px;
  margin-bottom: 4px;
  border-bottom: 1px solid var(--border);
}

.ruler-mark {
  position: absolute;
  bottom: 2px;
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--text-dim);
  transform: translateX(-50%);
}

.lock-row {
  display: flex;
  align-items: center;
  margin-bottom: 6px;
}

.lock-pid {
  width: 56px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  flex-shrink: 0;
  text-align: right;
  padding-right: 8px;
}

.lock-bar {
  flex: 1;
  height: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  position: relative;
  overflow: hidden;
}

.lock-range {
  position: absolute;
  top: 2px;
  height: calc(100% - 4px);
  border-radius: 3px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s;
}

.lock-range.lock-read {
  background: var(--accent2)33;
  border: 1px solid var(--accent2)88;
}

.lock-range.lock-write {
  background: var(--accent)33;
  border: 1px solid var(--accent)88;
}

.lock-type-label {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
}

.lock-read .lock-type-label { color: var(--accent2); }
.lock-write .lock-type-label { color: var(--accent); }

.lock-legend {
  display: flex;
  gap: 16px;
  font-size: 11px;
  color: var(--text-dim);
  margin-bottom: 12px;
  padding-left: 60px;
}

.lock-legend-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

.lock-list-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 12px;
}

.lock-list-table th {
  text-align: left;
  padding: 4px 10px;
  font-size: 10px;
  color: var(--text-dim);
  font-weight: 600;
  text-transform: uppercase;
  border-bottom: 1px solid var(--border);
}

.lock-list-table td {
  padding: 4px 10px;
  border-bottom: 1px solid var(--border)33;
}

.lock-list-table tr.added td {
  background: var(--green)18;
}

.lock-type-r { color: var(--accent2); font-weight: 600; }
.lock-type-w { color: var(--accent); font-weight: 600; }

/* Pipe diagram */
.pipe-diagram {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  margin-bottom: 12px;
  transition: all 0.3s;
}

.pipe-diagram.pipe-wrote {
  border-color: var(--green)88;
  box-shadow: 0 0 8px var(--green)22;
}

.pipe-diagram.pipe-read-anim {
  border-color: var(--accent2)88;
  box-shadow: 0 0 8px var(--accent2)22;
}

.pipe-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
}

.pipe-label {
  font-weight: 700;
  color: var(--accent2);
  font-size: 13px;
}

.pipe-usage {
  color: var(--text-dim);
}

.pipe-badge {
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 9px;
  font-weight: 700;
  text-transform: uppercase;
}

.pipe-badge-closed {
  background: var(--accent)22;
  color: var(--accent);
  border: 1px solid var(--accent)44;
}

.pipe-flow {
  display: flex;
  align-items: center;
  gap: 8px;
}

.pipe-endpoints {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 80px;
}

.pipe-endpoint {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  text-align: center;
  color: var(--text);
}

.pipe-endpoint.writer {
  border-color: var(--green)88;
  color: var(--green);
}

.pipe-endpoint.reader {
  border-color: var(--accent2)88;
  color: var(--accent2);
}

.pipe-endpoint.closed {
  border-style: dashed;
  color: var(--text-dim);
  opacity: 0.5;
}

.pipe-fd {
  font-size: 9px;
  color: var(--text-dim);
}

.pipe-arrow {
  color: var(--text-dim);
  font-size: 14px;
  flex-shrink: 0;
}

.pipe-buffer-container {
  flex: 1;
  min-width: 0;
}

.pipe-buffer {
  height: 36px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  display: flex;
  overflow: hidden;
}

.pipe-chunk {
  background: var(--green)44;
  border-right: 1px solid var(--green)66;
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 0;
  transition: width 0.3s;
}

.chunk-label {
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--green);
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  padding: 0 4px;
}

.pipe-empty {
  color: var(--text-dim);
  font-size: 12px;
  padding: 20px;
  text-align: center;
}

/* Pipe process list */
.pipe-process-list {
  margin-top: 8px;
}

.pipe-proc {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  border-bottom: 1px solid var(--border)33;
}

.pipe-proc.zombie { opacity: 0.5; }

.pipe-proc-name {
  font-weight: 600;
  color: var(--text);
  min-width: 80px;
}

.pipe-proc-pid {
  color: var(--accent2);
  min-width: 50px;
}

.pipe-proc-fds {
  color: var(--text-dim);
}

/* Signal grid */
.signal-grid {
  overflow-x: auto;
}

.sig-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 12px;
}

.sig-header th {
  text-align: left;
  padding: 6px 10px;
  font-size: 10px;
  color: var(--text-dim);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  border-bottom: 2px solid var(--border);
}

.sig-table tr {
  opacity: 0.45;
  transition: all 0.3s;
}

.sig-table tr.sig-active {
  opacity: 1;
}

.sig-table tr:hover {
  opacity: 1;
  background: var(--bg);
}

.sig-name {
  padding: 4px 10px;
  font-weight: 500;
  color: var(--text);
  border-bottom: 1px solid var(--border)33;
  white-space: nowrap;
}

.sig-cell {
  padding: 4px 10px;
  border-bottom: 1px solid var(--border)33;
  text-align: center;
  transition: background 0.3s;
}

.sig-cell.cell-added {
  background: var(--green)22;
}

.sig-cell.cell-removed {
  background: var(--accent)15;
}

.sig-cell.cell-changed {
  background: var(--yellow)22;
}

.sig-disp {
  text-align: left;
}

.bit-off {
  display: inline-block;
  width: 14px;
  height: 14px;
  border-radius: 3px;
  background: var(--border)44;
  border: 1px solid var(--border);
}

.bit-on {
  display: inline-block;
  width: 14px;
  height: 14px;
  border-radius: 3px;
  animation: appear 0.3s ease-out;
}

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

.disp-ignore {
  color: var(--text-dim);
  font-size: 11px;
  font-style: italic;
}

.disp-handler {
  color: var(--accent);
  font-weight: 600;
  font-size: 11px;
}

/* Signal event log */
.signal-log-section {
  margin-top: 16px;
}

.signal-log {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  max-height: 150px;
  overflow-y: auto;
}

.log-entry {
  padding: 2px 0;
  color: var(--text-dim);
  border-bottom: 1px solid var(--border)22;
}

.log-entry.log-new {
  color: var(--text);
  font-weight: 500;
  animation: appear 0.3s ease-out;
}

.log-entry.log-data-flow {
  background: var(--green)11;
  border-left: 2px solid var(--green)66;
  padding-left: 8px;
  color: var(--green);
}

/* Controls */
.controls {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 0;
}

.controls .step-info {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-dim);
  margin-left: 8px;
}

button.btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}

button.btn:hover { background: var(--border); }
button.btn:disabled { opacity: 0.4; cursor: default; }

button.btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

/* Lesson panel */
.lesson-panel {
  background: var(--accent2)11;
  border: 1px solid var(--accent2)44;
  color: var(--text);
  padding: 10px 14px;
  border-radius: 6px;
  font-size: 12px;
  line-height: 1.7;
  border-left: 3px solid var(--accent2);
}