/* ═══════════════════════════════════════════
   Design tokens — light (default)
   ═══════════════════════════════════════════ */
:root {
  /* Sidebar / hero gradient — intentionally dark in both themes */
  --fc-gradient-from: rgb(5, 39, 103);
  --fc-gradient-to: #3a0647;

  /* Page surfaces */
  --fc-bg:             #f0f2f5;
  --fc-surface:        #ffffff;
  --fc-surface-hover:  #f9fafb;
  --fc-surface-subtle: #f3f4f6;
  --fc-surface-raised: #f8fafc;

  /* Text */
  --fc-text:           #111827;
  --fc-text-heading:   #1a1a2e;
  --fc-text-secondary: #334155;
  --fc-text-muted:     #64748b;
  --fc-text-subtle:    #9ca3af;

  /* Borders */
  --fc-border:         #e2e8f0;
  --fc-border-subtle:  #f1f5f9;
  --fc-border-strong:  #d1d5db;

  /* Blue (word groups, study, form focus) */
  --fc-blue:           #1b6ec2;
  --fc-blue-hover:     #1861ac;
  --fc-blue-bg:        #e0edff;
  --fc-blue-bg-hover:  #bfdbfe;
  --fc-blue-focus:     rgba(27, 110, 194, 0.2);

  /* Purple accent (brand, AI Platforms, newer UI) */
  --fc-purple:         #7c3aed;
  --fc-purple-hover:   #6d28d9;
  --fc-purple-bg:      #f5f3ff;
  --fc-purple-bg-hover:#ede9fe;
  --fc-purple-subtle:  #e9d5ff;
  --fc-purple-glow:    rgba(124, 58, 237, 0.35);

  /* Semantic */
  --fc-success:        #16a34a;
  --fc-success-bg:     #f0fdf4;
  --fc-success-border: #bbf7d0;
  --fc-danger:         #dc2626;
  --fc-danger-bg:      #fef2f2;
  --fc-danger-border:  #fca5a5;
  --fc-danger-bg-hover:#fee2e2;
  --fc-warning-bg:     #fff7ed;
  --fc-warning-text:   #c2410c;

  /* Amber / yellow (learned badge) */
  --fc-amber-bg:       #fef9c3;
  --fc-amber-text:     #a16207;

  /* Indigo (AI example chips) */
  --fc-indigo-bg:      #f0f4ff;
  --fc-indigo-border:  #c7d2fe;
  --fc-indigo-text:    #1e1b4b;

  /* Shadows */
  --fc-shadow-sm: 0 1px 3px rgba(0, 0, 0, .06);
  --fc-shadow-md: 0 4px 12px rgba(0, 0, 0, .10);
  --fc-shadow-lg: 0 8px 24px rgba(0, 0, 0, .14);
}

/* ═══════════════════════════════════════════
   Design tokens — dark
   ═══════════════════════════════════════════ */
[data-theme="dark"] {
  --fc-bg:             #0f1117;
  --fc-surface:        #1a1d2e;
  --fc-surface-hover:  #222538;
  --fc-surface-subtle: #1e2132;
  --fc-surface-raised: #1e2132;

  --fc-text:           #e2e8f0;
  --fc-text-heading:   #f1f5f9;
  --fc-text-secondary: #cbd5e1;
  --fc-text-muted:     #94a3b8;
  --fc-text-subtle:    #64748b;

  --fc-border:         #2d3748;
  --fc-border-subtle:  #1e2533;
  --fc-border-strong:  #374151;

  --fc-blue:           #60a5fa;
  --fc-blue-hover:     #3b82f6;
  --fc-blue-bg:        #1e3a5f;
  --fc-blue-bg-hover:  #1a3352;
  --fc-blue-focus:     rgba(96, 165, 250, 0.25);

  --fc-purple:         #a78bfa;
  --fc-purple-hover:   #8b5cf6;
  --fc-purple-bg:      #1e1b4b;
  --fc-purple-bg-hover:#2d2165;
  --fc-purple-subtle:  #3730a3;
  --fc-purple-glow:    rgba(167, 139, 250, 0.35);

  --fc-success:        #4ade80;
  --fc-success-bg:     #052e16;
  --fc-success-border: #14532d;
  --fc-danger:         #f87171;
  --fc-danger-bg:      #1c0a0a;
  --fc-danger-border:  #7f1d1d;
  --fc-danger-bg-hover:#2c0f0f;
  --fc-warning-bg:     #1c0f00;
  --fc-warning-text:   #fb923c;

  --fc-amber-bg:       #1c1800;
  --fc-amber-text:     #facc15;

  --fc-indigo-bg:      #1e1b4b;
  --fc-indigo-border:  #3730a3;
  --fc-indigo-text:    #a5b4fc;

  --fc-shadow-sm: 0 1px 4px rgba(0, 0, 0, .30);
  --fc-shadow-md: 0 4px 16px rgba(0, 0, 0, .40);
  --fc-shadow-lg: 0 8px 28px rgba(0, 0, 0, .55);
}

/* ═══════════════════════════════════════════
   Theme toggle icons
   CSS-driven so the correct icon shows from the very first render
   (before Blazor's interactive circuit connects and reads localStorage).
   ═══════════════════════════════════════════ */
.theme-icon--sun  { display: none; }
[data-theme="dark"] .theme-icon--sun  { display: inline; }
[data-theme="dark"] .theme-icon--moon { display: none; }

/* ═══════════════════════════════════════════
   Base
   ═══════════════════════════════════════════ */
html, body {
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  background-color: var(--fc-bg);
  color: var(--fc-text);
}

a, .btn-link {
  color: var(--fc-blue);
}

.btn-primary {
  color: #fff;
  background-color: var(--fc-blue);
  border-color: var(--fc-blue-hover);
}

.btn:focus, .btn:active:focus, .btn-link.nav-link:focus,
.form-control:focus, .form-check-input:focus {
  box-shadow: 0 0 0 0.1rem var(--fc-surface), 0 0 0 0.25rem var(--fc-blue);
}

/* ═══════════════════════════════════════════
   Shared form elements (overrides Bootstrap
   where our pages define custom .form-control)
   ═══════════════════════════════════════════ */
.form-control {
  background-color: var(--fc-surface);
  color: var(--fc-text);
  border-color: var(--fc-border-strong);
}

.form-control:focus {
  background-color: var(--fc-surface);
  color: var(--fc-text);
  border-color: var(--fc-blue);
  box-shadow: 0 0 0 3px var(--fc-blue-focus);
}

.form-select {
  background-color: var(--fc-surface);
  color: var(--fc-text);
  border-color: var(--fc-border-strong);
}

/* ═══════════════════════════════════════════
   Layout helpers
   ═══════════════════════════════════════════ */
.content {
  padding-top: 1.1rem;
}

/* Page header */
.page-header {
  margin-bottom: 1.75rem;
}

.page-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--fc-text-heading);
  margin: 0 0 0.25rem;
}

.page-subtitle {
  color: var(--fc-text-muted);
  margin: 0;
  font-size: 0.95rem;
}

.back-link {
  display: inline-block;
  font-size: 0.875rem;
  color: var(--fc-text-muted);
  text-decoration: none;
  margin-bottom: 0.5rem;
  transition: color 0.15s;
}

.back-link:hover {
  color: var(--fc-blue);
  text-decoration: none;
}

/* Section title */
.section-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--fc-text-heading);
  margin-bottom: 0.75rem;
}

/* Loading state */
.loading-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 4rem 2rem;
  color: var(--fc-text-muted);
}

.spinner {
  width: 2.5rem;
  height: 2.5rem;
  border: 3px solid var(--fc-border);
  border-top-color: var(--fc-blue);
  border-radius: 50%;
  animation: fc-spin 0.7s linear infinite;
  margin-bottom: 1rem;
}

@keyframes fc-spin {
  to { transform: rotate(360deg); }
}

/* Empty state */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 4rem 2rem;
  color: var(--fc-text-muted);
  text-align: center;
}

.empty-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
}

/* ═══════════════════════════════════════════
   Shared form layout
   ═══════════════════════════════════════════ */
.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--fc-text-secondary);
  margin-bottom: 0.4rem;
}

.required-star {
  color: var(--fc-danger);
  margin-left: 2px;
}

.form-hint {
  font-size: 0.775rem;
  color: var(--fc-text-subtle);
  margin-top: 0.3rem;
}

.form-hint-inline {
  color: var(--fc-text-subtle);
  font-weight: 400;
  font-size: 0.8rem;
}

.form-error {
  display: block;
  font-size: 0.8rem;
  color: var(--fc-danger);
  margin-top: 0.3rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-actions {
  display: flex;
  gap: 0.75rem;
  justify-content: flex-end;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--fc-border-subtle);
}

/* ═══════════════════════════════════════════
   Shared card / surface
   ═══════════════════════════════════════════ */
.create-card {
  background: var(--fc-surface);
  border: 1px solid var(--fc-border);
  border-radius: 0.75rem;
  padding: 2rem;
  max-width: 520px;
  box-shadow: var(--fc-shadow-sm);
}

/* ═══════════════════════════════════════════
   Shared buttons
   ═══════════════════════════════════════════ */
.btn-submit {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--fc-gradient-from), var(--fc-blue));
  color: white;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 0.6rem 1.5rem;
  border: none;
  border-radius: 0.5rem;
  cursor: pointer;
  transition: opacity 0.15s, transform 0.15s;
}

.btn-submit:hover:not(:disabled) {
  opacity: 0.9;
  transform: translateY(-1px);
}

.btn-submit:disabled {
  opacity: 0.65;
  cursor: not-allowed;
}

.btn-spinner {
  width: 1rem;
  height: 1rem;
  border: 2px solid rgba(255, 255, 255, 0.4);
  border-top-color: white;
  border-radius: 50%;
  animation: fc-spin 0.7s linear infinite;
  display: inline-block;
}

/* ═══════════════════════════════════════════
   Alerts
   ═══════════════════════════════════════════ */
.alert {
  border-radius: 0.5rem;
  padding: 0.75rem 1rem;
  font-size: 0.875rem;
}

.alert-danger {
  background: var(--fc-danger-bg);
  color: var(--fc-danger);
  border: 1px solid var(--fc-danger-border);
}

/* ═══════════════════════════════════════════
   Bootstrap overrides for dark mode
   ═══════════════════════════════════════════ */
h1:focus { outline: none; }

.valid.modified:not([type=checkbox]) { outline: 1px solid var(--fc-success); }
.invalid { outline: 1px solid var(--fc-danger); }
.validation-message { color: var(--fc-danger); }

.darker-border-checkbox.form-check-input { border-color: var(--fc-text-subtle); }

.blazor-error-boundary {
  background: url(data:image/svg+xml;base64,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) no-repeat 1rem/1.8rem, #b32121;
  padding: 1rem 1rem 1rem 3.7rem;
  color: white;
}

.blazor-error-boundary::after { content: "An error has occurred." }