/* ── FILE: pages/style.css ─────────────────────────────────────
   [v1.0] Design system + component styles — Big 4 consulting grade
   §04 full implementation */

/* ═══════ CSS CUSTOM PROPERTIES (§04.1) ═══════ */

/* ── LIGHT THEME (DEFAULT) ─────────────────────────────── */
[data-theme='light'], :root {
  --color-bg-base:      #F8F9FB;
  --color-bg-surface:   #FFFFFF;
  --color-bg-elevated:  #F1F5F9;
  --color-border:       #E2E8F0;
  --color-border-focus: #6366F1;
  --color-accent:       #6366F1;
  --color-accent-hover: #4F46E5;
  --color-accent-glow:  rgba(99,102,241,0.18);
  --color-text-primary: #0F172A;
  --color-text-secondary:#475569;
  --color-text-muted:   #94A3B8;
  --color-success:      #059669;
  --color-warning:      #D97706;
  --color-error:        #DC2626;
  --color-gold:         #B45309;
  --nav-bg:             rgba(255,255,255,0.82);
  --card-shadow:        0 1px 3px rgba(0,0,0,0.08);
  --modal-shadow:       0 8px 32px rgba(0,0,0,0.18);
  --dropdown-shadow:    0 2px 8px rgba(0,0,0,0.12);
}

/* ── DARK THEME ─────────────────────────────────────────── */
[data-theme='dark'] {
  --color-bg-base:      #0A0A0F;
  --color-bg-surface:   #111118;
  --color-bg-elevated:  #1A1A24;
  --color-border:       #2A2A38;
  --color-text-primary: #F0F0F5;
  --color-text-secondary:#9090A8;
  --color-text-muted:   #55556A;
  --color-gold:         #D4AF37;
  --nav-bg:             rgba(17,17,24,0.85);
  --card-shadow:        0 1px 3px rgba(0,0,0,0.3);
  --modal-shadow:       0 8px 32px rgba(0,0,0,0.5);
  --dropdown-shadow:    0 2px 8px rgba(0,0,0,0.4);
}

/* ── SPACING SYSTEM (4px grid) ── */
:root {
  --space-1:4px;  --space-2:8px;  --space-3:12px;  --space-4:16px;
  --space-5:20px; --space-6:24px; --space-8:32px;  --space-10:40px;
  --space-12:48px;--space-16:64px;--space-20:80px;
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ═══════ RESET & BASE ═══════ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--color-bg-base);
  color: var(--color-text-primary);
  line-height: 1.6;
  min-height: 100vh;
  transition: background-color var(--transition), color var(--transition);
}

/* ── Skip link (§06.9) ── */
.skip-link {
  position: absolute;
  top: -40px;
  left: 8px;
  background: var(--color-accent);
  color: #fff;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  z-index: 9999;
  font-size: 0.875rem;
  text-decoration: none;
}
.skip-link:focus { top: 8px; }

/* ═══════ NAVIGATION BAR (§04.2) ═══════ */
.nav-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 56px;
  background: var(--nav-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
  transition: box-shadow var(--transition);
}
.nav-bar.scrolled { box-shadow: var(--dropdown-shadow); }
.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-6);
}
.nav-left { display: flex; align-items: center; gap: var(--space-3); }
.nav-logo { display: flex; align-items: center; }
.nav-title {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-text-primary);
  letter-spacing: -0.02em;
}
.nav-right { display: flex; align-items: center; gap: var(--space-4); }
.nav-badge-live {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-success);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-success);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.6; transform: scale(1.3); }
}

.theme-toggle {
  background: none;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 6px;
  cursor: pointer;
  color: var(--color-text-secondary);
  display: flex;
  align-items: center;
  transition: all var(--transition);
}
.theme-toggle:hover { border-color: var(--color-accent); color: var(--color-accent); }
[data-theme='light'] .icon-moon { display: none; }
[data-theme='dark'] .icon-sun { display: none; }

/* ═══════ HERO SECTION (§04.3) ═══════ */
.hero {
  margin-top: 56px;
  padding: var(--space-16) var(--space-6) var(--space-12);
  background:
    radial-gradient(ellipse at 20% 50%, rgba(99,102,241,0.12) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 20%, rgba(99,102,241,0.08) 0%, transparent 50%),
    var(--color-bg-base);
  text-align: center;
  position: relative;
}
.hero-inner { max-width: 680px; margin: 0 auto; }
.hero-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--color-text-primary);
  margin-bottom: var(--space-3);
}
.hero-subtitle {
  font-size: 1.0625rem;
  color: var(--color-text-secondary);
  max-width: 560px;
  margin: 0 auto var(--space-5);
  line-height: 1.6;
}
.hero-meta { display: flex; justify-content: center; gap: var(--space-2); flex-wrap: wrap; }
.hero-badge {
  font-size: 0.6875rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--color-bg-elevated);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  letter-spacing: 0.04em;
}
.hero-badge--domain { background: rgba(99,102,241,0.1); color: var(--color-accent); border-color: rgba(99,102,241,0.2); }
.hero-line {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--color-accent), transparent);
  animation: shimmer 3s ease-in-out infinite;
}
@keyframes shimmer {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 1; }
}

/* ═══════ MAIN CONTENT (§04.4–04.6) ═══════ */
.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-8) var(--space-6);
}
.main-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
}
@media (min-width: 900px) {
  .main-grid { grid-template-columns: 380px 1fr; }
}

/* ── Card base ── */
.card {
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--card-shadow);
  padding: var(--space-6);
}

/* ── Section header ── */
.section-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}
.section-header-bar {
  width: 3px;
  height: 16px;
  background: var(--color-accent);
  border-radius: 2px;
}
.section-header-text {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.file-count {
  margin-left: auto;
  font-size: 0.6875rem;
  font-weight: 600;
  background: var(--color-accent);
  color: #fff;
  padding: 1px 8px;
  border-radius: 999px;
}

/* ── Presets (§06.13) ── */
.presets-row {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
  flex-wrap: wrap;
}
.presets-label {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  font-weight: 500;
}
.preset-btn {
  font-size: 0.6875rem;
  padding: 3px 10px;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: var(--color-bg-elevated);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  font-family: inherit;
}
.preset-btn:hover { border-color: var(--color-accent); color: var(--color-accent); }
.preset-clear {
  font-size: 0.6875rem;
  color: var(--color-text-muted);
  text-decoration: none;
}
.preset-clear:hover { color: var(--color-error); }

/* ── Validation summary (§06.12) ── */
.validation-summary {
  background: rgba(220,38,38,0.06);
  border: 1px solid rgba(220,38,38,0.2);
  border-radius: var(--radius-md);
  padding: var(--space-3) var(--space-4);
  margin-bottom: var(--space-4);
  animation: slideDown 300ms ease;
}
.validation-summary-title {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-error);
  margin-bottom: var(--space-1);
}
.validation-summary-list {
  list-style: none;
  padding: 0;
}
.validation-summary-list li {
  font-size: 0.8125rem;
  color: var(--color-error);
  padding: 2px 0;
}
.validation-summary-list li a {
  color: var(--color-error);
  text-decoration: underline;
  cursor: pointer;
}
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Drop zone ── */
.drop-zone {
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8) var(--space-4);
  text-align: center;
  cursor: pointer;
  transition: all var(--transition);
  background: var(--color-bg-elevated);
  margin-bottom: var(--space-4);
}
.drop-zone:hover, .drop-zone:focus-visible {
  border-color: var(--color-accent);
  background: var(--color-accent-glow);
}
.drop-zone.drag-over {
  border-color: var(--color-accent);
  background: var(--color-accent-glow);
  border-style: solid;
}
.drop-zone-icon { color: var(--color-text-muted); margin-bottom: var(--space-2); }
.drop-zone-text {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-primary);
  margin-bottom: var(--space-1);
}
.drop-zone-hint { font-size: 0.8125rem; color: var(--color-text-muted); }

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: inherit;
  font-size: 0.8125rem;
  font-weight: 600;
  padding: 0 var(--space-4);
  height: 40px;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
  min-width: 0;
}
.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}
.btn-primary {
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-hover));
  color: #fff;
}
.btn-primary:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px var(--color-accent-glow);
}
.btn-ghost {
  background: transparent;
  color: var(--color-accent);
  border: 1.5px solid var(--color-accent);
}
.btn-ghost:hover:not(:disabled) { background: var(--color-accent-glow); }
.btn-danger { background: var(--color-error); color: #fff; }
.btn-danger:hover:not(:disabled) { background: #B91C1C; }
.btn-sm { height: 30px; font-size: 0.75rem; padding: 0 var(--space-3); }

.btn-cta {
  width: 100%;
  height: 48px;
  min-width: 160px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-hover));
  color: #fff;
  font-size: 0.9375rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-4);
  font-family: inherit;
}
.btn-cta:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px var(--color-accent-glow);
}
.btn-cta:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-cta.loading { pointer-events: none; }
.btn-cta.success {
  background: var(--color-success);
}
.btn-cta-shortcut {
  font-size: 0.6875rem;
  opacity: 0.7;
  font-weight: 400;
}

.input-actions { display: flex; gap: var(--space-2); margin-bottom: var(--space-4); }

/* ── File queue ── */
.file-list {
  list-style: none;
  max-height: 160px;
  overflow-y: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-2);
}
.file-list-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-size: 0.8125rem;
  border-bottom: 1px solid var(--color-border);
  cursor: pointer;
  transition: background var(--transition);
}
.file-list-item:last-child { border-bottom: none; }
.file-list-item:hover { background: var(--color-bg-elevated); }
.file-list-item.selected { background: var(--color-accent-glow); }
.file-list-item-name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-list-item-check {
  width: 16px; height: 16px;
  border: 1.5px solid var(--color-border);
  border-radius: 3px;
  flex-shrink: 0;
  transition: all var(--transition);
}
.file-list-item.selected .file-list-item-check {
  background: var(--color-accent);
  border-color: var(--color-accent);
}
.file-queue-actions { display: flex; gap: var(--space-2); justify-content: flex-end; }

/* ── Offline banner (§06.14) ── */
.offline-banner {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  background: rgba(217,119,6,0.1);
  border: 1px solid rgba(217,119,6,0.3);
  border-radius: var(--radius-md);
  font-size: 0.8125rem;
  color: var(--color-warning);
  margin-top: var(--space-3);
}

/* ── Session stats (§06.11) ── */
.session-stats {
  margin-top: var(--space-4);
  text-align: center;
}
.session-stats-text {
  font-size: 0.6875rem;
  color: var(--color-text-muted);
}

/* ═══════ OUTPUT PANEL ═══════ */
.output-panel {
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--card-shadow);
  padding: var(--space-6);
  border-top: 3px solid var(--color-accent);
  min-height: 400px;
}

/* ── Skeleton (§04.7) ── */
.skeleton-bar {
  height: 16px;
  background: var(--color-bg-elevated);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-3);
  animation: shimmerSkeleton 1.5s ease-in-out infinite;
}
.skeleton-bar--wide { width: 60%; }
.skeleton-bar--medium { width: 80%; }
.skeleton-bar--full { width: 100%; }
.skeleton-row { display: flex; gap: var(--space-3); margin-bottom: var(--space-4); }
.skeleton-card {
  flex: 1;
  height: 72px;
  background: var(--color-bg-elevated);
  border-radius: var(--radius-md);
  animation: shimmerSkeleton 1.5s ease-in-out infinite;
}
@keyframes shimmerSkeleton {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

/* ── Empty state (§04.9) ── */
.empty-state {
  text-align: center;
  padding: var(--space-16) var(--space-6);
}
.empty-state-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin: var(--space-4) 0 var(--space-2);
}
.empty-state-text { font-size: 0.875rem; color: var(--color-text-muted); }

/* ── Error state (§04.9) ── */
.error-state {
  text-align: center;
  padding: var(--space-10) var(--space-6);
  background: rgba(220,38,38,0.04);
  border-radius: var(--radius-md);
}
.error-state-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-error);
  margin: var(--space-3) 0 var(--space-2);
}
.error-state-text {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
}

/* ── Results container ── */
.results-container { animation: fadeInUp 300ms ease; }
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Metrics row ── */
.metrics-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--space-3);
  margin-bottom: var(--space-5);
}
.metric-card {
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  text-align: center;
}
.metric-value {
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 2px;
  font-variant-numeric: tabular-nums;
}
.metric-label {
  font-size: 0.6875rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* ── Confidence (§06.7) ── */
.confidence-row { margin-bottom: var(--space-3); }
.confidence-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 3px 12px;
  border-radius: 999px;
}
.confidence-badge--high { background: rgba(5,150,105,0.12); color: var(--color-success); }
.confidence-badge--review { background: rgba(217,119,6,0.12); color: var(--color-warning); }

/* ── Processing time (§06.10) ── */
.processing-time {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}
.processing-time--slow { color: var(--color-warning); }

/* ── Search row ── */
.search-row {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
  flex-wrap: wrap;
}
.search-input-wrap {
  position: relative;
  flex: 1;
  min-width: 200px;
}
.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-muted);
  pointer-events: none;
}
.search-input {
  width: 100%;
  height: 40px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  color: var(--color-text-primary);
  font-family: inherit;
  font-size: 0.8125rem;
  padding: 0 var(--space-4) 0 36px;
  transition: all var(--transition);
}
.search-input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-glow);
}
.search-input::placeholder { color: var(--color-text-muted); font-style: italic; }

.filter-select {
  height: 40px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  color: var(--color-text-primary);
  font-family: inherit;
  font-size: 0.8125rem;
  padding: 0 var(--space-3);
  cursor: pointer;
  transition: all var(--transition);
}
.filter-select:focus {
  outline: none;
  border-color: var(--color-accent);
}

.record-count {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  font-weight: 500;
  white-space: nowrap;
}

/* ── Data table ── */
.table-container {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
  max-height: 500px;
  overflow-y: auto;
}
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8125rem;
}
.data-table th {
  position: sticky;
  top: 0;
  background: var(--color-accent);
  color: #fff;
  padding: var(--space-2) var(--space-3);
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  white-space: nowrap;
  cursor: pointer;
  user-select: none;
  text-align: left;
  z-index: 1;
}
.data-table th:hover { background: var(--color-accent-hover); }
.data-table td {
  padding: var(--space-2) var(--space-3);
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
  max-width: 200px;
  overflow: hidden;
  text-overflow: ellipsis;
}
.data-table tr:nth-child(even) td { background: var(--color-bg-elevated); }
.data-table tr:hover td { background: var(--color-accent-glow); }
.data-table td.numeric {
  font-variant-numeric: tabular-nums;
  text-align: right;
  font-family: 'Inter', monospace;
}
.data-table td.center { text-align: center; }
.data-table td.status-ok { color: var(--color-success); font-weight: 600; }
.data-table td.status-error { color: var(--color-error); font-weight: 600; }

/* ── Audit breakdown (§06.8) ── */
.audit-breakdown {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
}
.audit-breakdown-summary {
  padding: var(--space-3) var(--space-4);
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  cursor: pointer;
  user-select: none;
}
.audit-breakdown-summary:hover { color: var(--color-accent); }
.audit-breakdown-content {
  padding: 0 var(--space-4) var(--space-4);
  font-size: 0.8125rem;
  line-height: 1.8;
}
.audit-step {
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-border);
  display: flex;
  gap: var(--space-3);
}
.audit-step:last-child { border-bottom: none; }
.audit-step-field { font-weight: 600; min-width: 180px; color: var(--color-text-secondary); }
.audit-step-value { color: var(--color-text-primary); }
.audit-step-formula { color: var(--color-text-muted); font-style: italic; font-size: 0.75rem; }

/* ── Export row ── */
.export-row {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
  margin-bottom: var(--space-3);
}

/* ── Result timestamp ── */
.result-timestamp {
  font-size: 0.6875rem;
  color: var(--color-text-muted);
  text-align: right;
}

/* ═══════ HISTORY DRAWER (§06.1) ═══════ */
.history-drawer {
  margin-top: var(--space-6);
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-4) var(--space-6);
}
.history-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-3);
}
.history-header h3 {
  font-size: 0.9375rem;
  font-weight: 600;
}
.history-item {
  padding: var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-2);
  font-size: 0.8125rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}
.history-item-info { flex: 1; }
.history-item-time { font-size: 0.6875rem; color: var(--color-text-muted); }
.history-item-summary { color: var(--color-text-secondary); }

/* ═══════ ABOUT SECTION (§05) ═══════ */
.about-section {
  background: linear-gradient(180deg, var(--color-bg-base), var(--color-bg-elevated));
  padding: var(--space-16) var(--space-6);
}
.about-inner { max-width: 1200px; margin: 0 auto; }
.about-title {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-3);
  text-align: center;
}
.about-summary {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  text-align: center;
  max-width: 640px;
  margin: 0 auto var(--space-8);
  line-height: 1.6;
}
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-4);
  margin-bottom: var(--space-8);
}
.feature-card {
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  display: flex;
  gap: var(--space-3);
  align-items: flex-start;
  transition: all var(--transition);
}
.feature-card:hover { box-shadow: var(--card-shadow); transform: translateY(-2px); }
.feature-card-icon { color: var(--color-accent); flex-shrink: 0; }
.feature-card-name { font-size: 0.875rem; font-weight: 600; margin-bottom: 2px; }
.feature-card-desc { font-size: 0.8125rem; color: var(--color-text-secondary); line-height: 1.5; }

.ideal-for { text-align: center; }
.ideal-for-label {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-right: var(--space-2);
}
.pill {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 500;
  padding: 4px 14px;
  border-radius: 999px;
  background: var(--color-accent-glow);
  color: var(--color-accent);
  margin: var(--space-1);
}

/* ═══════ FOOTER (§07.1) ═══════ */
.footer {
  padding: var(--space-6);
  border-top: 1px solid var(--color-border);
}
.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.footer-text { font-size: 0.8125rem; color: var(--color-text-secondary); }
.footer-link {
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition);
}
.footer-link:hover { text-decoration: underline; color: var(--color-accent); }

/* ═══════ MODAL (§07.2) ═══════ */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeIn 200ms ease;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.modal-card {
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--modal-shadow);
  max-width: 480px;
  width: 90%;
  padding: var(--space-8);
  position: relative;
  text-align: center;
  animation: modalIn 200ms ease;
}
.modal-card--wide { max-width: 560px; text-align: left; }
@keyframes modalIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
.modal-close {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  background: none;
  border: none;
  font-size: 1.25rem;
  color: var(--color-text-muted);
  cursor: pointer;
  padding: var(--space-1);
  line-height: 1;
  transition: color var(--transition);
}
.modal-close:hover { color: var(--color-text-primary); }
.modal-avatar {
  width: 80px;
  height: 80px;
  margin: 0 auto var(--space-4);
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-hover));
  display: flex;
  align-items: center;
  justify-content: center;
}
.avatar-initials {
  font-size: 1.5rem;
  font-weight: 700;
  color: #fff;
}
.modal-name {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: var(--space-1);
}
.modal-title-text {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
}
.modal-bio {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: var(--space-5);
}
.modal-social {
  display: flex;
  justify-content: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}
.social-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1.5px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: all var(--transition);
}
.social-btn:hover { border-color: var(--color-accent); color: var(--color-accent); }
.modal-creds {
  display: flex;
  justify-content: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}
.cred-pill {
  font-size: 0.6875rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--color-bg-elevated);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}

/* ── Shortcuts modal ── */
.shortcuts-grid {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-2) var(--space-4);
  margin-top: var(--space-4);
}
.shortcut-key {
  font-family: 'Inter', monospace;
  font-size: 0.75rem;
  font-weight: 600;
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 2px 8px;
  white-space: nowrap;
}
.shortcut-desc {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  align-self: center;
}

/* ═══════ TOAST NOTIFICATIONS (§04.8) ═══════ */
.toast-container {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  z-index: 300;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  max-width: 380px;
}
.toast {
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--modal-shadow);
  padding: var(--space-3) var(--space-4);
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  animation: toastIn 300ms ease;
  font-size: 0.8125rem;
}
.toast.removing { animation: toastOut 200ms ease forwards; }
@keyframes toastIn { from { opacity: 0; transform: translateX(110%); } to { opacity: 1; transform: translateX(0); } }
@keyframes toastOut { to { opacity: 0; transform: translateX(110%); } }
.toast-icon { flex-shrink: 0; margin-top: 2px; }
.toast-success .toast-icon { color: var(--color-success); }
.toast-error .toast-icon { color: var(--color-error); }
.toast-warning .toast-icon { color: var(--color-warning); }
.toast-info .toast-icon { color: var(--color-accent); }
.toast-body { flex: 1; }
.toast-close {
  background: none;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  font-size: 1rem;
  padding: 0;
  line-height: 1;
  flex-shrink: 0;
}
.toast-close:hover { color: var(--color-text-primary); }

/* ═══════ RESPONSIVE (§04.10) ═══════ */
@media (max-width: 640px) {
  .hero { padding: var(--space-10) var(--space-4) var(--space-8); }
  .hero-title { font-size: 1.5rem; }
  .main-content { padding: var(--space-4); }
  .nav-inner { padding: 0 var(--space-4); }
  .metrics-row { grid-template-columns: repeat(2, 1fr); }
  .export-row { flex-direction: column; }
  .export-row .btn { width: 100%; }
  .footer-inner { flex-direction: column; gap: var(--space-3); text-align: center; }
}

/* ═══════ FOCUS VISIBLE (§06.9) ═══════ */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}
button:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ═══════ SCROLLBAR ═══════ */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--color-bg-elevated); }
::-webkit-scrollbar-thumb { background: var(--color-border); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--color-text-muted); }