/* ==========================================================================
   FlowGit Landing Page — Axiom Design System
   Strictly implements DESIGN.md specifications
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:ital,wght@0,400;0,500;0,700;1,400&family=Inter:wght@400;500;600&display=swap');

:root {
  /* ── Axiom Colors ── */
  --color-void: #000000;
  --color-carbon: #111111;
  --color-graphite: #191919;
  --color-iron: #202020;
  --color-slate: #3a3a3a;
  --color-pewter: #505050;
  --color-steel: #606060;
  --color-ash: #7e7e7e;
  --color-fog: #b4b4b4;
  --color-chalk: #d9d9d9;
  --color-paper: #eeeeee;
  --color-ember: #da5c2c;
  --color-ember-hover: #e86b3a;
  --color-ember-active: #c54f22;

  /* Semantic Diff Colors (design-system-safe) */
  --diff-add-bg: #122414;
  --diff-add-border: #1e4522;
  --diff-add-text: #4ade80;
  --diff-del-bg: #271313;
  --diff-del-border: #4d2020;
  --diff-del-text: #f87171;

  /* ── Typography ── */
  --font-mono: 'BerkeleyMono', 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --font-sans: 'Inter', ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

  /* ── Type Scale ── */
  --text-caption: 12px;
  --leading-caption: 1.5;
  --text-body: 14px;
  --leading-body: 1.71;
  --text-heading-sm: 18px;
  --leading-heading-sm: 1.56;
  --text-heading: 20px;
  --leading-heading: 1.4;
  --text-heading-lg: 24px;
  --leading-heading-lg: 1.33;
  --text-display: 32px;
  --leading-display: 1.25;

  /* ── Spacing (8px Base Unit) ── */
  --spacing-8: 8px;
  --spacing-16: 16px;
  --spacing-24: 24px;
  --spacing-32: 32px;
  --spacing-40: 40px;
  --spacing-48: 48px;
  --spacing-64: 64px;
  --spacing-80: 80px;
  --spacing-96: 96px;

  /* ── Layout & Radii ── */
  --page-max-width: 1200px;
  --section-gap: 64px;
  --card-padding: 32px;
  --radius-sm: 2px;
  --radius-full: 9999px;
  --shadow-subtle: rgba(0, 0, 0, 0.05) 0px 1px 2px 0px;
}

/* ── Reset & Base ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  background-color: var(--color-void);
  color: var(--color-paper);
  font-family: var(--font-mono);
  font-size: var(--text-body);
  line-height: var(--leading-body);
  letter-spacing: 0px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background-color: var(--color-void);
  color: var(--color-paper);
  overflow-x: hidden;
  min-height: 100vh;
}

::selection {
  background-color: var(--color-ember);
  color: var(--color-paper);
}

/* ── Custom Monospace Scrollbars ── */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: var(--color-void);
}

::-webkit-scrollbar-thumb {
  background: var(--color-slate);
  border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-pewter);
}

/* ── Links & Common ── */
a {
  color: inherit;
  text-decoration: none;
}

code, pre {
  font-family: var(--font-mono);
}

/* ── Container ── */
.container {
  width: 100%;
  max-width: var(--page-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-24);
}

/* ── Top Announcement Banner ── */
.announcement-banner {
  background-color: var(--color-carbon);
  border-bottom: 1px solid var(--color-iron);
  font-size: var(--text-caption);
  color: var(--color-paper);
  padding: 10px var(--spacing-16);
  position: relative;
  z-index: 100;
}

.announcement-content {
  max-width: var(--page-max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-16);
}

.announcement-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--color-ember);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.announcement-badge .pulse-dot {
  width: 6px;
  height: 6px;
  border-radius: var(--radius-full);
  background-color: var(--color-ember);
  box-shadow: 0 0 6px var(--color-ember);
}

.announcement-text {
  color: var(--color-fog);
  display: flex;
  align-items: center;
  gap: 8px;
}

.announcement-link {
  color: var(--color-paper);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s ease;
}

.announcement-link:hover {
  color: var(--color-ember);
}

.announcement-close {
  background: none;
  border: none;
  color: var(--color-steel);
  font-family: var(--font-mono);
  font-size: 14px;
  cursor: pointer;
  padding: 2px 6px;
  line-height: 1;
}

.announcement-close:hover {
  color: var(--color-paper);
}

/* ── Navigation Bar ── */
.nav-bar {
  position: sticky;
  top: 0;
  z-index: 90;
  background-color: var(--color-void);
  border-bottom: 1px solid var(--color-iron);
  height: 56px;
  display: flex;
  align-items: center;
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.brand-cluster {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.02em;
  color: var(--color-paper);
}

.brand-mark {
  color: var(--color-ember);
  font-size: 13px;
  line-height: 1;
}

.brand-badge {
  font-size: 11px;
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  background: var(--color-carbon);
  color: var(--color-steel);
  border: 1px solid var(--color-iron);
  letter-spacing: 0.04em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-24);
  list-style: none;
}

.nav-link {
  font-size: var(--text-body);
  color: var(--color-fog);
  transition: color 0.15s ease;
  position: relative;
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link:hover {
  color: var(--color-paper);
}

.nav-link .nav-index {
  color: var(--color-steel);
  font-size: 11px;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* ── Axiom Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1;
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  border: 1px solid transparent;
  transition: background-color 0.12s ease, border-color 0.12s ease, color 0.12s ease;
  white-space: nowrap;
}

.btn-sm {
  padding: 6px 12px;
  font-size: 12px;
}

.btn-lg {
  padding: 12px 20px;
  font-size: 15px;
}

/* Primary CTA: Filled Ember #da5c2c, #eeeeee text, 2px radius */
.btn-primary {
  background-color: var(--color-ember);
  color: var(--color-paper);
  font-weight: 700;
  border-color: var(--color-ember);
}

.btn-primary:hover {
  background-color: var(--color-ember-hover);
  border-color: var(--color-ember-hover);
}

.btn-primary:active {
  background-color: var(--color-ember-active);
}

/* Ghost Button: Transparent, 1px #3a3a3a border, #eeeeee text */
.btn-ghost {
  background-color: transparent;
  border-color: var(--color-slate);
  color: var(--color-paper);
  font-weight: 400;
}

.btn-ghost:hover {
  border-color: var(--color-pewter);
  background-color: var(--color-carbon);
}

.btn-secondary {
  background-color: var(--color-carbon);
  border-color: var(--color-iron);
  color: var(--color-paper);
}

.btn-secondary:hover {
  border-color: var(--color-slate);
  background-color: var(--color-graphite);
}

/* ── Typography & Headings ── */
.tag-label {
  font-size: var(--text-caption);
  color: var(--color-steel);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 400;
  margin-bottom: var(--spacing-8);
  display: block;
}

.heading-display {
  font-size: clamp(28px, 4vw, var(--text-display));
  line-height: var(--leading-display);
  font-weight: 700;
  color: var(--color-paper);
  letter-spacing: -0.02em;
}

.heading-lg {
  font-size: var(--text-heading-lg);
  line-height: var(--leading-heading-lg);
  font-weight: 700;
  color: var(--color-paper);
}

.heading-md {
  font-size: var(--text-heading);
  line-height: var(--leading-heading);
  font-weight: 700;
  color: var(--color-paper);
}

.heading-sm {
  font-size: var(--text-heading-sm);
  line-height: var(--leading-heading-sm);
  font-weight: 400;
  color: var(--color-paper);
}

.body-text {
  font-size: var(--text-body);
  line-height: var(--leading-body);
  color: var(--color-fog);
}

.muted-text {
  font-size: var(--text-caption);
  line-height: var(--leading-caption);
  color: var(--color-ash);
}

/* ── Hero Section ── */
.hero-section {
  position: relative;
  padding: var(--spacing-64) 0 var(--spacing-40) 0;
  overflow: hidden;
  background-color: var(--color-void);
}

.hero-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-40);
  position: relative;
  z-index: 2;
}

.hero-prompt {
  font-size: 13px;
  color: var(--color-ash);
  margin-bottom: var(--spacing-16);
  display: flex;
  align-items: center;
  gap: 8px;
}

.hero-prompt-dir {
  color: var(--color-ember);
  font-weight: 700;
}

.hero-prompt-cursor {
  display: inline-block;
  width: 8px;
  height: 15px;
  background-color: var(--color-ember);
  animation: blinkCursor 1s step-end infinite;
  vertical-align: text-bottom;
}

@keyframes blinkCursor {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.hero-headline {
  margin-bottom: var(--spacing-24);
  max-width: 900px;
}

.hero-description {
  max-width: 680px;
  font-size: 15px;
  color: var(--color-fog);
  line-height: 1.7;
  margin-bottom: var(--spacing-32);
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--spacing-16);
  margin-bottom: var(--spacing-32);
}

.hero-install-pill {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: var(--color-carbon);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: 8px 14px;
  font-size: 13px;
  color: var(--color-fog);
}

.hero-install-pill code {
  color: var(--color-paper);
}

.copy-btn-inline {
  background: none;
  border: none;
  color: var(--color-steel);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-slate);
  transition: all 0.12s ease;
}

.copy-btn-inline:hover {
  color: var(--color-paper);
  border-color: var(--color-pewter);
}

.hero-telemetry-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--spacing-24);
  padding-top: var(--spacing-24);
  border-top: 1px solid var(--color-iron);
}

.telemetry-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--color-steel);
}

.telemetry-item .dot {
  width: 5px;
  height: 5px;
  background-color: var(--color-ember);
  border-radius: var(--radius-full);
}

/* Arrow Decoration Field (DESIGN.md specification) */
.arrow-field-background {
  position: absolute;
  top: 10px;
  right: 0;
  width: 480px;
  height: 360px;
  opacity: 0.18;
  pointer-events: none;
  user-select: none;
  font-size: 14px;
  line-height: 18px;
  letter-spacing: 10px;
  color: var(--color-slate);
  overflow: hidden;
  font-family: var(--font-mono);
  white-space: pre-wrap;
  z-index: 1;
}

/* ── Interactive Product Showcase ── */
.showcase-wrapper {
  margin-top: var(--spacing-40);
  background-color: var(--color-carbon);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: var(--shadow-subtle);
}

/* Window Chrome / Titlebar */
.app-chrome {
  height: 38px;
  background-color: var(--color-void);
  border-bottom: 1px solid var(--color-iron);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--spacing-16);
  user-select: none;
}

.app-window-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.window-dot {
  width: 10px;
  height: 10px;
  border-radius: var(--radius-full);
  background-color: var(--color-slate);
}

.window-dot.close { background-color: #ef4444; }
.window-dot.min { background-color: #f59e0b; }
.window-dot.max { background-color: #10b981; }

.app-window-title {
  font-size: 12px;
  color: var(--color-fog);
  display: flex;
  align-items: center;
  gap: 8px;
}

.app-window-status {
  font-size: 11px;
  color: var(--color-steel);
  display: flex;
  align-items: center;
  gap: 6px;
}

.status-indicator-green {
  width: 6px;
  height: 6px;
  background: #22c55e;
  border-radius: var(--radius-full);
}

/* Product Mock Tab Bar */
.product-tab-bar {
  display: flex;
  align-items: center;
  background-color: var(--color-carbon);
  border-bottom: 1px solid var(--color-iron);
  padding: 0 var(--spacing-8);
  overflow-x: auto;
}

.product-tab {
  padding: 10px 16px;
  font-size: 12px;
  color: var(--color-fog);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  font-family: var(--font-mono);
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.12s ease;
  white-space: nowrap;
}

.product-tab:hover {
  color: var(--color-paper);
  background-color: rgba(255, 255, 255, 0.02);
}

.product-tab.active {
  color: var(--color-paper);
  border-bottom-color: var(--color-ember);
  background-color: var(--color-graphite);
}

/* Histogram Activity Bar (DESIGN.md specification) */
.histogram-row {
  display: flex;
  align-items: flex-end;
  gap: 3px;
  height: 24px;
  padding: 6px 16px;
  background-color: #0c0c0c;
  border-bottom: 1px solid var(--color-iron);
  user-select: none;
}

.histogram-label {
  font-size: 10px;
  color: var(--color-steel);
  margin-right: 12px;
  white-space: nowrap;
}

.histogram-bars-container {
  display: flex;
  align-items: flex-end;
  gap: 3px;
  height: 100%;
  flex: 1;
  overflow: hidden;
}

.histogram-bar {
  width: 6px;
  background-color: var(--color-slate);
  border-radius: 1px;
  transition: height 0.3s ease, background-color 0.2s ease;
}

.histogram-bar.active-accent {
  background-color: var(--color-ember);
}

.histogram-bar:hover {
  background-color: var(--color-chalk);
}

/* ── Interactive View Canvas Container ── */
.showcase-viewport {
  position: relative;
  height: 520px;
  background-color: var(--color-void);
  overflow: hidden;
}

.view-panel {
  display: none;
  width: 100%;
  height: 100%;
}

.view-panel.active {
  display: block;
}

/* ── TAB 1: Blueprint DAG Graph View ── */
.blueprint-graph-container {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  cursor: grab;
  /* Blueprint dot-grid canvas */
  background-color: #000000;
  background-image: radial-gradient(#202020 1px, transparent 1px);
  background-size: 24px 24px;
}

.blueprint-graph-container:active {
  cursor: grabbing;
}

.graph-controls-toolbar {
  position: absolute;
  top: 14px;
  left: 14px;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 8px;
  background-color: rgba(17, 17, 17, 0.95);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  backdrop-filter: blur(8px);
}

.graph-search-input {
  background: var(--color-void);
  border: 1px solid var(--color-iron);
  color: var(--color-paper);
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  width: 140px;
}

.graph-search-input:focus {
  outline: 1px solid var(--color-ember);
}

.graph-tool-btn {
  background: var(--color-graphite);
  border: 1px solid var(--color-iron);
  color: var(--color-fog);
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.12s ease;
}

.graph-tool-btn:hover {
  background: var(--color-slate);
  color: var(--color-paper);
}

.graph-hint {
  position: absolute;
  top: 14px;
  right: 14px;
  z-index: 20;
  font-size: 11px;
  color: var(--color-steel);
  background: rgba(17, 17, 17, 0.85);
  padding: 4px 8px;
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  pointer-events: none;
}

/* SVG DAG Elements */
.graph-svg-root {
  width: 100%;
  height: 100%;
  user-select: none;
}

.dag-edge {
  fill: none;
  stroke-width: 2px;
  stroke-linecap: round;
  transition: stroke 0.2s ease;
}

/* Node cards rendered via foreignObject or SVG rect */
.node-card {
  cursor: pointer;
  transition: transform 0.15s ease, filter 0.15s ease;
}

.node-card:hover {
  filter: brightness(1.2);
}

.node-card.selected rect.node-base {
  stroke: var(--color-ember) !important;
  stroke-width: 2px !important;
}

/* Minimap Radar */
.graph-minimap {
  position: absolute;
  bottom: 14px;
  right: 14px;
  width: 140px;
  height: 90px;
  background-color: rgba(17, 17, 17, 0.9);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  z-index: 20;
  overflow: hidden;
  pointer-events: none;
}

.minimap-viewport-box {
  position: absolute;
  border: 1px solid var(--color-ember);
  background-color: rgba(218, 92, 44, 0.15);
  pointer-events: none;
}

/* Interactive Commit Inspector Drawer */
.commit-inspector-drawer {
  position: absolute;
  top: 0;
  right: 0;
  width: 380px;
  height: 100%;
  background-color: var(--color-carbon);
  border-left: 1px solid var(--color-iron);
  z-index: 30;
  padding: var(--spacing-16);
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: -4px 0 16px rgba(0, 0, 0, 0.5);
}

.commit-inspector-drawer.open {
  transform: translateX(0);
}

.inspector-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--color-iron);
  padding-bottom: 12px;
  margin-bottom: 12px;
}

.inspector-hash {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-paper);
}

.inspector-close-btn {
  background: none;
  border: none;
  color: var(--color-steel);
  font-family: var(--font-mono);
  font-size: 16px;
  cursor: pointer;
}

.inspector-close-btn:hover {
  color: var(--color-paper);
}

.inspector-body {
  flex: 1;
  overflow-y: auto;
  font-size: 12px;
}

.inspector-field {
  margin-bottom: 10px;
}

.inspector-field-label {
  color: var(--color-steel);
  font-size: 11px;
  text-transform: uppercase;
  margin-bottom: 2px;
}

.inspector-field-val {
  color: var(--color-fog);
  line-height: 1.4;
}

.inspector-diff-preview {
  margin-top: 14px;
  background-color: var(--color-void);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: 8px;
  font-size: 11px;
  overflow-x: auto;
}

/* ── TAB 2: Staging & Changes View ── */
.staging-view-grid {
  display: grid;
  grid-template-columns: 320px 1fr;
  height: 100%;
}

.staging-sidebar {
  background-color: var(--color-carbon);
  border-right: 1px solid var(--color-iron);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.staging-section-header {
  padding: 10px 14px;
  background-color: var(--color-graphite);
  border-bottom: 1px solid var(--color-iron);
  font-size: 12px;
  font-weight: 700;
  color: var(--color-paper);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.staging-file-list {
  flex: 1;
  overflow-y: auto;
}

.staging-file-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 14px;
  border-bottom: 1px solid #1a1a1a;
  font-size: 12px;
  cursor: pointer;
  transition: background 0.1s ease;
}

.staging-file-row:hover {
  background-color: var(--color-graphite);
}

.staging-file-name {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--color-paper);
}

.file-status-letter {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 16px;
  height: 16px;
  font-size: 10px;
  font-weight: 700;
  border-radius: var(--radius-sm);
}

.status-m { background-color: #78350f; color: #fde047; }
.status-a { background-color: #14532d; color: #4ade80; }
.status-d { background-color: #7f1d1d; color: #f87171; }
.status-u { background-color: #374151; color: #9ca3af; }

.staging-action-btn {
  background: none;
  border: 1px solid var(--color-slate);
  color: var(--color-fog);
  font-size: 11px;
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-family: var(--font-mono);
}

.staging-action-btn:hover {
  color: var(--color-paper);
  border-color: var(--color-pewter);
}

.commit-form-panel {
  padding: 14px;
  border-top: 1px solid var(--color-iron);
  background-color: #0d0d0d;
}

.commit-textarea {
  width: 100%;
  height: 70px;
  background-color: var(--color-void);
  border: 1px solid var(--color-iron);
  color: var(--color-paper);
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 8px;
  border-radius: var(--radius-sm);
  resize: none;
  margin-bottom: 8px;
}

.commit-textarea:focus {
  outline: 1px solid var(--color-ember);
}

.commit-form-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.char-counter {
  font-size: 11px;
  color: var(--color-steel);
}

.staging-diff-preview-pane {
  background-color: var(--color-void);
  padding: var(--spacing-16);
  overflow-y: auto;
  font-size: 12px;
}

/* ── TAB 3: Advanced Diff Viewer View ── */
.diff-viewer-shell {
  height: 100%;
  display: flex;
  flex-direction: column;
}

.diff-toolbar {
  padding: 10px 16px;
  background-color: var(--color-graphite);
  border-bottom: 1px solid var(--color-iron);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.diff-file-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-paper);
  display: flex;
  align-items: center;
  gap: 8px;
}

.diff-toggle-group {
  display: flex;
  align-items: center;
  border: 1px solid var(--color-slate);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.diff-toggle-btn {
  background: var(--color-carbon);
  color: var(--color-fog);
  border: none;
  padding: 4px 10px;
  font-size: 11px;
  font-family: var(--font-mono);
  cursor: pointer;
}

.diff-toggle-btn.active {
  background-color: var(--color-slate);
  color: var(--color-paper);
}

.diff-content-body {
  flex: 1;
  overflow: auto;
  background-color: var(--color-void);
  font-size: 12px;
  line-height: 1.5;
}

.diff-line {
  display: flex;
  width: 100%;
  min-width: 600px;
}

.diff-num-col {
  width: 48px;
  text-align: right;
  padding: 0 8px;
  color: var(--color-steel);
  user-select: none;
  border-right: 1px solid var(--color-iron);
  font-size: 11px;
}

.diff-text-col {
  padding: 0 12px;
  white-space: pre;
  flex: 1;
}

.diff-line.added {
  background-color: var(--diff-add-bg);
  color: var(--diff-add-text);
}

.diff-line.deleted {
  background-color: var(--diff-del-bg);
  color: var(--diff-del-text);
}

.diff-line.hunk-header {
  background-color: var(--color-carbon);
  color: var(--color-ember);
  font-weight: 700;
  border-top: 1px solid var(--color-iron);
  border-bottom: 1px solid var(--color-iron);
}

/* ── TAB 4: Branch Matrix View ── */
.branches-matrix-shell {
  padding: var(--spacing-24);
  height: 100%;
  overflow-y: auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-24);
}

.branch-group-box {
  background-color: var(--color-carbon);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: var(--spacing-16);
}

.branch-group-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-paper);
  margin-bottom: var(--spacing-16);
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--color-iron);
  padding-bottom: 8px;
}

.branch-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background-color: var(--color-graphite);
  border: 1px solid var(--color-iron);
  margin-bottom: 8px;
  font-size: 12px;
}

.branch-item.current {
  border-left: 2px solid var(--color-ember);
}

.branch-name {
  font-weight: 700;
  color: var(--color-paper);
  display: flex;
  align-items: center;
  gap: 8px;
}

.branch-stats {
  font-size: 11px;
  color: var(--color-fog);
  display: flex;
  align-items: center;
  gap: 8px;
}

.sync-badge {
  color: #38bdf8;
}

/* ── Features Deep Dive Section ── */
.section-wrapper {
  padding: var(--spacing-80) 0;
  border-bottom: 1px solid var(--color-iron);
}

.section-header {
  margin-bottom: var(--spacing-48);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-24);
}

/* Axiom Card: #191919 background, 2px radius, 32px padding */
.axiom-card {
  background-color: var(--color-graphite);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: var(--card-padding);
  position: relative;
  transition: border-color 0.15s ease;
}

.axiom-card:hover {
  border-color: var(--color-slate);
}

/* Editorial / Signature card: 2px solid #da5c2c left border */
.axiom-card.editorial {
  border-left: 2px solid var(--color-ember);
}

.card-num {
  font-size: 11px;
  color: var(--color-steel);
  margin-bottom: var(--spacing-16);
  letter-spacing: 0.08em;
}

.card-title {
  font-size: var(--text-heading-sm);
  font-weight: 700;
  color: var(--color-paper);
  margin-bottom: 12px;
}

.card-body {
  font-size: var(--text-body);
  line-height: var(--leading-body);
  color: var(--color-fog);
  margin-bottom: var(--spacing-24);
}

.card-list {
  list-style: none;
  font-size: 12px;
  color: var(--color-fog);
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-top: 1px solid var(--color-iron);
  padding-top: var(--spacing-16);
}

.card-list li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.card-list li::before {
  content: '>';
  color: var(--color-ember);
  font-weight: 700;
}

/* ── Interactive Command & Architecture Section ── */
.arch-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-32);
  align-items: flex-start;
}

.terminal-box {
  background-color: var(--color-carbon);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.terminal-tab-header {
  display: flex;
  align-items: center;
  background-color: var(--color-void);
  border-bottom: 1px solid var(--color-iron);
}

.terminal-tab-btn {
  background: none;
  border: none;
  color: var(--color-fog);
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 10px 16px;
  cursor: pointer;
  border-bottom: 2px solid transparent;
}

.terminal-tab-btn.active {
  color: var(--color-paper);
  border-bottom-color: var(--color-ember);
  background-color: var(--color-carbon);
}

.terminal-code-body {
  padding: var(--spacing-24);
  font-size: 13px;
  line-height: 1.6;
  color: var(--color-paper);
  position: relative;
  overflow-x: auto;
}

.terminal-code-body pre {
  margin: 0;
}

.copy-floating-btn {
  position: absolute;
  top: 14px;
  right: 14px;
  background: var(--color-graphite);
  border: 1px solid var(--color-iron);
  color: var(--color-fog);
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.12s ease;
}

.copy-floating-btn:hover {
  border-color: var(--color-slate);
  color: var(--color-paper);
}

/* Architecture Table */
.data-table-container {
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  overflow-x: auto;
  background-color: var(--color-carbon);
}

.axiom-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
  text-align: left;
}

.axiom-table th {
  background-color: var(--color-graphite);
  color: var(--color-paper);
  font-weight: 700;
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-iron);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-size: 11px;
}

.axiom-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-iron);
  color: var(--color-fog);
}

.axiom-table tr:last-child td {
  border-bottom: none;
}

.axiom-table tr:hover td {
  background-color: var(--color-graphite);
}

/* ── Customer / Developer Case Studies (DESIGN.md specification) ── */
.testimonials-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-24);
}

.case-study-card {
  background-color: var(--color-graphite);
  border-radius: var(--radius-sm);
  padding: var(--card-padding);
  border: 1px solid var(--color-iron);
  border-left: 2px solid var(--color-ember); /* Category mark */
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.case-study-logo {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-paper);
  letter-spacing: 0.05em;
  margin-bottom: var(--spacing-16);
  display: flex;
  align-items: center;
  gap: 8px;
}

.case-study-headline {
  font-size: var(--text-heading-sm);
  font-weight: 400;
  color: var(--color-paper);
  margin-bottom: 14px;
}

.case-study-quote-block {
  background-color: var(--color-carbon);
  padding: var(--spacing-16);
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-iron);
  font-size: var(--text-body);
  font-style: italic;
  color: var(--color-fog);
  margin-bottom: var(--spacing-24);
  line-height: 1.6;
}

.case-study-footer {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: var(--spacing-16);
}

.case-study-avatar {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  background-color: var(--color-iron);
  border: 1px solid var(--color-slate);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 700;
  color: var(--color-paper);
}

.case-study-author-info {
  display: flex;
  flex-direction: column;
}

.case-study-name {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-paper);
}

.case-study-role {
  font-size: 12px;
  color: var(--color-steel);
}

.case-study-link {
  font-size: 13px;
  color: var(--color-paper);
  text-decoration: underline;
  text-underline-offset: 3px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: color 0.12s ease;
}

.case-study-link:hover {
  color: var(--color-ember);
}

/* ── Download Matrix Section ── */
.download-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-24);
  margin-bottom: var(--spacing-40);
}

.download-card {
  background-color: var(--color-carbon);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: var(--card-padding);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
}

.download-card.highlight {
  border-color: var(--color-ember);
  background-color: var(--color-graphite);
}

.download-badge-recom {
  position: absolute;
  top: 14px;
  right: 14px;
  font-size: 10px;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background-color: var(--color-ember);
  color: var(--color-paper);
  font-weight: 700;
  letter-spacing: 0.05em;
}

.download-card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-paper);
  margin-bottom: 6px;
}

.download-card-meta {
  font-size: 12px;
  color: var(--color-steel);
  margin-bottom: var(--spacing-24);
}

.download-card-details {
  list-style: none;
  font-size: 12px;
  color: var(--color-fog);
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: var(--spacing-32);
}

.download-card-details li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--color-iron);
  padding-bottom: 6px;
}

.sys-reqs-strip {
  background-color: var(--color-carbon);
  border: 1px solid var(--color-iron);
  border-radius: var(--radius-sm);
  padding: var(--spacing-16) var(--spacing-24);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-16);
  font-size: 12px;
  color: var(--color-fog);
}

/* ── Keyboard Shortcuts Bottom Bar ── */
.kbd-bar {
  background-color: var(--color-carbon);
  border-top: 1px solid var(--color-iron);
  padding: 12px 0;
  font-size: 12px;
}

.kbd-items-wrapper {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-24);
  color: var(--color-steel);
}

.kbd-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

kbd {
  background: var(--color-graphite);
  border: 1px solid var(--color-slate);
  border-radius: var(--radius-sm);
  padding: 2px 6px;
  color: var(--color-paper);
  font-size: 11px;
  font-family: var(--font-mono);
}

/* ── Footer ── */
.site-footer {
  background-color: var(--color-void);
  border-top: 1px solid var(--color-iron);
  padding: var(--spacing-64) 0 var(--spacing-32) 0;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-48);
  margin-bottom: var(--spacing-64);
}

.footer-col-title {
  font-size: 12px;
  font-weight: 700;
  color: var(--color-paper);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--spacing-16);
}

.footer-link-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 13px;
}

.footer-link {
  color: var(--color-fog);
  transition: color 0.15s ease;
}

.footer-link:hover {
  color: var(--color-paper);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--color-iron);
  padding-top: var(--spacing-24);
  font-size: 12px;
  color: var(--color-steel);
}

/* ── Toast Feedback Notification ── */
.toast-notice {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background-color: var(--color-carbon);
  border: 1px solid var(--color-ember);
  border-radius: var(--radius-sm);
  padding: 10px 18px;
  font-size: 12px;
  color: var(--color-paper);
  display: flex;
  align-items: center;
  gap: 8px;
  z-index: 1000;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.8);
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.toast-notice.show {
  opacity: 1;
  transform: translateY(0);
}

/* ── Responsive Breakpoints ── */
@media (max-width: 1024px) {
  .feature-grid,
  .testimonials-row,
  .download-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .arch-grid {
    grid-template-columns: 1fr;
  }

  .footer-top {
    grid-template-columns: 1fr 1fr;
  }

  .nav-links {
    display: none;
  }
}

@media (max-width: 680px) {
  .feature-grid,
  .testimonials-row,
  .download-grid {
    grid-template-columns: 1fr;
  }

  .staging-view-grid {
    grid-template-columns: 1fr;
  }

  .staging-diff-preview-pane {
    display: none;
  }

  .branches-matrix-shell {
    grid-template-columns: 1fr;
  }

  .footer-top {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
  }
}