:root {
  --bg-app: #0f172a;
  --bg-panel: #1e293b;
  --bg-card: #162032;
  --bg-card-hover: #1f2d46;
  --bg-input: #0b1120;
  --border-color: #334155;
  --border-focus: #38bdf8;
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --accent: #38bdf8;
  --accent-soft: rgba(56, 189, 248, 0.15);
  --write-set: #10b981;
  --write-set-bg: rgba(16, 185, 129, 0.14);
  --write-reset: #f59e0b;
  --write-reset-bg: rgba(245, 158, 11, 0.14);

  /* PLC Variable Type Colors */
  --type-E-fg: #34d399;
  --type-E-bg: rgba(16, 185, 129, 0.14);
  --type-E-bd: rgba(52, 211, 153, 0.45);

  --type-B-fg: #60a5fa;
  --type-B-bg: rgba(59, 130, 246, 0.14);
  --type-B-bd: rgba(96, 165, 250, 0.45);

  --type-A-fg: #f472b6;
  --type-A-bg: rgba(236, 72, 153, 0.14);
  --type-A-bd: rgba(244, 114, 182, 0.45);

  --type-R-fg: #f87171;
  --type-R-bg: rgba(239, 68, 68, 0.14);
  --type-R-bd: rgba(248, 113, 113, 0.45);

  --type-T-fg: #fbbf24;
  --type-T-bg: rgba(245, 158, 11, 0.14);
  --type-T-bd: rgba(251, 191, 36, 0.45);

  --type-M-fg: #c084fc;
  --type-M-bg: rgba(168, 85, 247, 0.14);
  --type-M-bd: rgba(192, 132, 252, 0.45);

  --type-L-fg: #2dd4bf;
  --type-L-bg: rgba(20, 184, 166, 0.14);
  --type-L-bd: rgba(45, 212, 191, 0.45);

  --type-J-fg: #fb923c;
  --type-J-bg: rgba(249, 115, 22, 0.14);
  --type-J-bd: rgba(251, 146, 60, 0.45);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Inter, sans-serif;
  background-color: var(--bg-app);
  color: var(--text-main);
  height: 100vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.hidden {
  display: none !important;
}

/* Header / Topbar */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 1.25rem;
  background-color: var(--bg-panel);
  border-bottom: 1px solid var(--border-color);
  flex-shrink: 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 260px;
}

.brand-badge {
  background: linear-gradient(135deg, #0284c7, #2563eb);
  color: #fff;
  font-weight: 800;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  padding: 0.45rem 0.65rem;
  border-radius: 6px;
  box-shadow: 0 2px 8px rgba(2, 132, 199, 0.35);
}

.brand h1 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
}

.subtitle {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.search-wrapper {
  position: relative;
  flex: 1;
  max-width: 560px;
}

.search-wrapper input {
  width: 100%;
  padding: 0.55rem 2.2rem 0.55rem 0.9rem;
  background-color: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: var(--text-main);
  font-size: 0.88rem;
  outline: none;
  transition: border-color 0.15s;
}

.search-wrapper input:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.2);
}

.btn-ghost {
  position: absolute;
  right: 0.45rem;
  top: 50%;
  transform: translateY(-50%);
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.25rem 0.4rem;
  font-size: 0.85rem;
}

.topbar-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.mode-group,
.view-tabs {
  display: flex;
  align-items: center;
  background-color: var(--bg-input);
  padding: 0.2rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

.control-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  padding: 0 0.5rem;
}

.mode-btn,
.tab-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.38rem 0.7rem;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.15s;
}

.mode-btn.active,
.tab-btn.active {
  background-color: var(--bg-panel);
  color: var(--accent);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

/* Navigation Trail Bar */
.nav-trail-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.45rem 1.25rem;
  background-color: #131c2e;
  border-bottom: 1px solid var(--border-color);
  flex-shrink: 0;
  overflow-x: auto;
}

.nav-buttons {
  display: flex;
  gap: 0.35rem;
}

.btn-nav {
  background-color: var(--bg-panel);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  font-size: 0.76rem;
  font-weight: 600;
  padding: 0.25rem 0.6rem;
  border-radius: 5px;
  cursor: pointer;
}

.btn-nav:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-nav:not(:disabled):hover {
  border-color: var(--accent);
  color: var(--accent);
}

.breadcrumb-label {
  font-size: 0.75rem;
  color: var(--text-dim);
  white-space: nowrap;
}

.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex: 1;
  overflow-x: auto;
}

.crumb-btn {
  background-color: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.74rem;
  padding: 0.18rem 0.5rem;
  border-radius: 4px;
  cursor: pointer;
  white-space: nowrap;
}

.crumb-btn.active {
  border-color: var(--accent);
  color: var(--accent);
  background-color: var(--accent-soft);
}

.crumb-sep {
  color: var(--text-dim);
  font-size: 0.75rem;
}

.legend-pills {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex-shrink: 0;
}

.type-pill {
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.15rem 0.45rem;
  border-radius: 4px;
  border: 1px solid transparent;
  white-space: nowrap;
}

.type-E, .type-EA { color: var(--type-E-fg); background: var(--type-E-bg); border-color: var(--type-E-bd); }
.type-B { color: var(--type-B-fg); background: var(--type-B-bg); border-color: var(--type-B-bd); }
.type-A, .type-SA { color: var(--type-A-fg); background: var(--type-A-bg); border-color: var(--type-A-bd); }
.type-R { color: var(--type-R-fg); background: var(--type-R-bg); border-color: var(--type-R-bd); }
.type-T { color: var(--type-T-fg); background: var(--type-T-bg); border-color: var(--type-T-bd); }
.type-M, .type-C { color: var(--type-M-fg); background: var(--type-M-bg); border-color: var(--type-M-bd); }
.type-L { color: var(--type-L-fg); background: var(--type-L-bg); border-color: var(--type-L-bd); }
.type-J, .type-S { color: var(--type-J-fg); background: var(--type-J-bg); border-color: var(--type-J-bd); }

/* Workspace Split Layout */
.workspace {
  display: grid;
  grid-template-columns: 1fr 450px;
  flex: 1;
  min-height: 0;
}

.main-pane {
  display: flex;
  flex-direction: column;
  min-height: 0;
  border-right: 1px solid var(--border-color);
}

.filter-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  padding: 0.6rem 1.25rem;
  background-color: var(--bg-panel);
  border-bottom: 1px solid var(--border-color);
  flex-shrink: 0;
}

.filter-item {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.filter-item select {
  background-color: var(--bg-input);
  color: var(--text-main);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 0.35rem 0.6rem;
  font-size: 0.8rem;
  outline: none;
}

.type-filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.filter-chip {
  background-color: var(--bg-input);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.76rem;
  font-weight: 600;
  padding: 0.3rem 0.6rem;
  border-radius: 6px;
  cursor: pointer;
}

.filter-chip.active {
  background-color: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
}

.filter-stats {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-left: auto;
}

.scroll-container {
  flex: 1;
  overflow-y: auto;
  padding: 1rem 1.25rem;
}

/* Section Headers in Program */
.section-header {
  position: sticky;
  top: -1rem;
  z-index: 5;
  background-color: rgba(15, 23, 42, 0.95);
  backdrop-filter: blur(6px);
  padding: 0.55rem 0.85rem;
  margin: 1rem 0 0.5rem 0;
  border-left: 3px solid var(--accent);
  border-bottom: 1px solid var(--border-color);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.02em;
}

.section-header:first-child {
  margin-top: 0;
}

/* Sequential Equation Row */
.eq-card {
  display: grid;
  grid-template-columns: 74px 1fr 270px;
  align-items: center;
  gap: 0.85rem;
  padding: 0.65rem 0.85rem;
  margin-bottom: 0.45rem;
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  transition: background-color 0.15s, border-color 0.15s, box-shadow 0.2s;
}

.eq-card:hover {
  background-color: var(--bg-card-hover);
}

.eq-card.selected-seq {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.25);
  background-color: #1a2942;
}

.eq-card.flash-highlight {
  animation: pulseHighlight 1.8s ease-out;
}

@keyframes pulseHighlight {
  0% { box-shadow: 0 0 0 4px rgba(56, 189, 248, 0.75); background-color: #1e3a5f; }
  100% { box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.25); }
}

.seq-badge {
  font-family: "JetBrains Mono", "Fira Code", monospace;
  font-size: 0.84rem;
  font-weight: 700;
  color: #38bdf8;
  background-color: rgba(56, 189, 248, 0.1);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: 6px;
  padding: 0.3rem 0.45rem;
  text-align: center;
  cursor: pointer;
}

.eq-formula {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.28rem;
  font-family: "JetBrains Mono", "Fira Code", monospace;
}

.op-token {
  color: #94a3b8;
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0 0.12rem;
}

.op-bracket {
  color: #f59e0b;
  font-weight: 800;
  font-size: 1rem;
  padding: 0 0.1rem;
}

.op-equals {
  color: #e2e8f0;
  font-weight: 800;
  font-size: 0.95rem;
  margin: 0 0.25rem;
  padding: 0.1rem 0.35rem;
  background: rgba(255, 255, 255, 0.07);
  border-radius: 4px;
}

.timer-meta-badge {
  font-size: 0.74rem;
  color: var(--type-T-fg);
  background: rgba(245, 158, 11, 0.1);
  border: 1px dashed rgba(251, 191, 36, 0.4);
  padding: 0.18rem 0.45rem;
  border-radius: 4px;
}

/* Interactive Variable Chip inside Equation */
.var-chip {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 0.2rem 0.48rem;
  border-radius: 6px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.1s, box-shadow 0.15s, filter 0.15s;
  text-align: center;
  line-height: 1.15;
}

.var-chip:hover {
  transform: translateY(-1px);
  filter: brightness(1.15);
}

.var-chip.active-var {
  box-shadow: 0 0 0 2px #fff, 0 0 10px var(--accent);
}

.var-chip-top {
  font-family: "JetBrains Mono", "Fira Code", monospace;
  font-size: 0.8rem;
  font-weight: 700;
}

.var-chip.negated .var-chip-top {
  text-decoration: overline;
}

.var-chip-sub {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 0.66rem;
  font-weight: 500;
  opacity: 0.88;
  max-width: 110px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.var-chip.rhs-chip {
  border-width: 2px;
}

.eq-target-summary {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  border-left: 2px solid var(--border-color);
  padding-left: 0.75rem;
  font-size: 0.78rem;
}

.target-Action-tag {
  display: inline-block;
  font-size: 0.66rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.1rem 0.38rem;
  border-radius: 4px;
  width: fit-content;
}

.tag-SET, .tag-ASSIGN { color: var(--write-set); background: var(--write-set-bg); }
.tag-RESET { color: var(--write-reset); background: var(--write-reset-bg); }
.tag-CALL, .tag-RETURN { color: var(--type-L-fg); background: var(--type-L-bg); }
.tag-JUMP, .tag-BRANCH, .tag-GOTO { color: var(--type-J-fg); background: var(--type-J-bg); }
.tag-NOP { color: var(--text-dim); background: rgba(255, 255, 255, 0.05); }

.target-comment-text {
  color: var(--text-main);
  font-weight: 500;
  line-height: 1.25;
}

.target-mnemo-text {
  color: var(--text-muted);
  font-family: monospace;
  font-size: 0.72rem;
}

/* Variables Dictionary Table */
.vars-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.82rem;
}

.vars-table th {
  position: sticky;
  top: -1rem;
  background-color: var(--bg-panel);
  color: var(--text-muted);
  text-align: left;
  padding: 0.65rem 0.75rem;
  border-bottom: 2px solid var(--border-color);
  font-weight: 600;
}

.vars-table td {
  padding: 0.55rem 0.75rem;
  border-bottom: 1px solid var(--border-color);
}

.vars-table tr {
  cursor: pointer;
  transition: background-color 0.12s;
}

.vars-table tbody tr:hover {
  background-color: var(--bg-card-hover);
}

.vars-table tbody tr.active-row {
  background-color: rgba(56, 189, 248, 0.12);
}

.count-badge {
  display: inline-block;
  padding: 0.12rem 0.45rem;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 700;
  background-color: rgba(255, 255, 255, 0.07);
}

/* Right Inspector Pane */
.inspector-pane {
  background-color: var(--bg-panel);
  display: flex;
  flex-direction: column;
  min-height: 0;
  overflow-y: auto;
}

.inspector-content {
  padding: 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}

.inspector-empty {
  text-align: center;
  padding: 3rem 1.25rem;
  color: var(--text-muted);
}

.inspector-empty h3 {
  color: var(--text-main);
  margin-bottom: 0.5rem;
  font-size: 1rem;
}

.inspector-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 1rem;
}

.var-header-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.6rem;
}

.var-big-code {
  font-family: "JetBrains Mono", monospace;
  font-size: 1.25rem;
  font-weight: 800;
  padding: 0.25rem 0.65rem;
  border-radius: 6px;
}

.var-mnemo-badge {
  font-family: monospace;
  font-size: 0.92rem;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.2rem 0.55rem;
  border-radius: 5px;
  font-weight: 700;
}

.var-comment-box {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 0.65rem;
  line-height: 1.35;
}

.var-meta-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem;
  font-size: 0.76rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-color);
  padding-top: 0.6rem;
}

.meta-label {
  color: var(--text-dim);
  display: block;
  font-size: 0.7rem;
}

.meta-value {
  color: var(--text-main);
  font-weight: 600;
}

.xref-section-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  margin-bottom: 0.6rem;
}

.xref-list {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.xref-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.7rem 0.8rem;
  transition: border-color 0.15s;
}

.xref-item:hover {
  border-color: var(--accent);
}

.xref-item.xref-write-set {
  border-left: 4px solid var(--write-set);
}

.xref-item.xref-write-reset {
  border-left: 4px solid var(--write-reset);
}

.xref-item.xref-read {
  border-left: 4px solid #38bdf8;
}

.xref-item-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.45rem;
}

.btn-jump-seq {
  background-color: var(--accent-soft);
  border: 1px solid rgba(56, 189, 248, 0.4);
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.22rem 0.6rem;
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.15s;
}

.btn-jump-seq:hover {
  background-color: var(--accent);
  color: #0f172a;
}

.xref-role-badge {
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.12rem 0.45rem;
  border-radius: 4px;
}

.role-WRITE_SET { color: var(--write-set); background: var(--write-set-bg); }
.role-WRITE_RESET { color: var(--write-reset); background: var(--write-reset-bg); }
.role-READ_NORM { color: #38bdf8; background: rgba(56, 189, 248, 0.14); }
.role-READ_NOT { color: #f472b6; background: rgba(244, 114, 182, 0.14); }
.role-TIMER_USE, .role-TIMER_PRESET { color: #fbbf24; background: rgba(251, 191, 36, 0.14); }
.role-CALL_CALC { color: var(--type-L-fg); background: var(--type-L-bg); }

.calc-entry-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0.45rem 0.75rem;
  margin: 0.75rem 0 0.25rem 0;
  background: rgba(20, 184, 166, 0.12);
  border: 1px solid rgba(45, 212, 191, 0.4);
  border-left: 4px solid var(--type-L-fg);
  border-radius: 6px;
  font-size: 0.8rem;
  color: #5eead4;
  font-weight: 600;
}

.calc-entry-callers {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.btn-branch-jump {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  background-color: rgba(249, 115, 22, 0.14);
  border: 1px solid rgba(251, 146, 60, 0.45);
  color: var(--type-J-fg);
  font-family: "JetBrains Mono", monospace;
  font-size: 0.76rem;
  font-weight: 700;
  padding: 0.2rem 0.5rem;
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.15s;
}

.btn-branch-jump:hover {
  background-color: var(--type-J-fg);
  color: #0f172a;
}

.calc-const-badge {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.8rem;
  font-weight: 700;
  color: #fde68a;
  background: rgba(251, 191, 36, 0.12);
  border: 1px solid rgba(251, 191, 36, 0.3);
  padding: 0.16rem 0.45rem;
  border-radius: 5px;
}

.calc-func-badge {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.76rem;
  font-weight: 700;
  color: #c084fc;
  background: rgba(168, 85, 247, 0.14);
  border: 1px solid rgba(192, 132, 252, 0.35);
  padding: 0.16rem 0.45rem;
  border-radius: 5px;
}

.calc-return-badge {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.76rem;
  font-weight: 700;
  color: var(--type-L-fg);
  background: var(--type-L-bg);
  border: 1px solid var(--type-L-bd);
  padding: 0.18rem 0.5rem;
  border-radius: 5px;
}

.filter-checkbox-label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.79rem;
  color: var(--text-muted);
  cursor: pointer;
  user-select: none;
}

.seq-badge.calc-badge {
  color: var(--type-L-fg);
  background-color: var(--type-L-bg);
  border-color: var(--type-L-bd);
}

.xref-eq-preview {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.22rem;
  margin-bottom: 0.4rem;
  padding: 0.4rem;
  background-color: rgba(15, 23, 42, 0.65);
  border-radius: 6px;
}

.xref-context-desc {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.origin-banner {
  padding: 0.6rem 0.75rem;
  border-radius: 6px;
  font-size: 0.79rem;
  background-color: rgba(45, 212, 191, 0.1);
  border: 1px solid rgba(45, 212, 191, 0.35);
  color: #5eead4;
  line-height: 1.35;
}

@media (max-width: 1100px) {
  .workspace {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 360px;
  }
  .eq-card {
    grid-template-columns: 64px 1fr;
  }
  .eq-target-summary {
    grid-column: 1 / -1;
    border-left: none;
    border-top: 1px solid var(--border-color);
    padding-left: 0;
    padding-top: 0.4rem;
  }
}