@charset "UTF-8";
/**
 * Full Skin — Auto-generated by generate-full-skin.py
 * Primary: #4f46e5  Accent: #10b981
 * Do not edit manually — regenerate via Phase 6 pipeline.
 */

/* ═══ Base Overrides ═══ */

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

::selection { background: #e4e3fb; color: #272372; }
::-moz-selection { background: #e4e3fb; color: #272372; }

*:focus-visible {
  outline: 3px solid #4f46e5;
  outline-offset: 2px;
  border-radius: 4px;
}

/* ═══ Scrollbar ═══ */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: #f7f7fd; }
::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, #4f46e5 0%, #433bc2 100%);
  border-radius: 5px; border: 2px solid #f7f7fd;
}
::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(180deg, #433bc2 0%, #3731a0 100%);
}

/* ═══ Body Background ═══ */
body {
  background: linear-gradient(135deg, #f7f7fd 0%, #f8f9fa 60%, #f5fcf9 100%);
  background-attachment: fixed;
}

/* ═══ Typography ═══ */

.page-header h1 {
  font-size: 2rem;
  font-weight: 700;
  color: #231f67;
  line-height: 1.3;
  font-family: var(--font-heading, system-ui, sans-serif);
}

.page-header .subtitle {
  color: #2b267d;
  font-size: 1.05rem;
  margin-top: 0.4rem;
}

/* ═══ Hero — Archetype: minimal-clean ═══ */

.page-header {
  background: #ffffff;
  border-bottom: 1px solid #cdcbf7;
  padding: 1.5rem 1.5rem 1rem;
}
.hero {
  background: #ffffff;
  border-bottom: 1px solid #cdcbf7;
  padding: 3rem 2rem 2.5rem;
  text-align: center;
}
.hero h1 {
  font-size: 2.4rem; font-weight: 700; color: #1b1850;
  font-family: var(--font-heading);
}
.hero .subtitle {
  font-size: 1.1rem; color: #2b267d;
  margin-top: 0.75rem; max-width: 550px; margin-left: auto; margin-right: auto;
}
/* Hero stats */
.hero-stats { display: flex; justify-content: center; gap: 2rem; margin-top: 1.5rem; flex-wrap: wrap; }
.stat-item { text-align: center; padding: 0.8rem 1.2rem; background: #ffffff; border: 1px solid #cdcbf7; border-radius: 6px; }
.stat-number { display: block; font-size: 1.6rem; font-weight: 800; color: #4f46e5; font-family: var(--font-heading); }
.stat-label { display: block; font-size: 0.85rem; color: #6b7280; margin-top: 0.15rem; }


/* ═══ Breadcrumb ═══ */
.breadcrumb {
  background: #f7f7fd; border: 1px solid #cdcbf7;
  border-radius: 4px; padding: 0.6rem 1rem; margin-bottom: 1rem;
}
.breadcrumb ol { display: flex; flex-wrap: wrap; gap: 0.3rem; list-style: none; padding: 0; margin: 0; font-size: 0.875rem; color: #6b7280; }
.breadcrumb a { color: #4f46e5; text-decoration: none; }
.breadcrumb a:hover { color: #433bc2; text-decoration: underline; }
.breadcrumb li:not(:last-child)::after { content: '›'; color: #d1d5db; font-weight: 600; margin-left: 0.3rem; }
.breadcrumb li:last-child { color: var(--site-text, #1f2937); font-weight: 600; }


/* ═══ Set Switcher ═══ */
.set-switcher {
  background: white; border: 1px solid #cdcbf7;
  border-radius: 10px; box-shadow: 0 1px 3px rgba(79,70,229,0.06);
}
.set-switcher-label { font-size: 1rem; font-weight: 600; color: var(--site-text, #1f2937); }
.set-btn {
  background: white; border: 2px solid #cdcbf7;
  border-radius: 4px; color: var(--site-text, #1f2937);
  font-size: 1rem; font-weight: 600; cursor: pointer; transition: all 150ms ease;
}
.set-btn:hover { border-color: #4f46e5; background: #f0f0fc; }
.set-btn.active { background: #4f46e5; color: white; border-color: #433bc2; }

/* ═══ Buttons ═══ */
.btn {
  font-size: 1rem; font-weight: 600; cursor: pointer;
  border: 2px solid transparent; border-radius: 4px;
  background: white; color: var(--site-text, #1f2937);
  box-shadow: 0 1px 3px rgba(79,70,229,0.06); transition: all 150ms ease;
}
.btn:hover { box-shadow: 0 4px 8px rgba(79,70,229,0.12); transform: translateY(-1px); }
.btn-primary { background: #4f46e5; color: white; border-color: #433bc2; }
.btn-primary:hover { background: #433bc2; }
.btn-success, .btn-answers { background: #10b981; color: white; border-color: #0d9d6d; }
.btn-success:hover, .btn-answers:hover { background: #0d9d6d; }
.btn-check { background: #f59e0b; color: white; border-color: #d97706; }
.btn-check:hover { background: #d97706; }
.btn:focus-visible { outline: 3px solid #4f46e5; outline-offset: 3px; }


/* ═══ Intro Section ═══ */
.intro, .intro-section {
  background: linear-gradient(135deg, #f2f2fd 0%, #e9e8fb 100%);
  border: 1px solid #cdcbf7;
  border-radius: 10px; padding: 1.25rem 1.5rem; margin: 1rem 0;
}
.intro h3, .intro-section h3 { font-weight: 600; color: #231f67; }
.intro p, .intro-section p { color: #4a4a5a; line-height: 1.7; }
.intro strong, .intro-section strong { color: #1b1850; }

/* ═══ Body Content / Worksheet ═══ */
.body-content {
  background: white;
  border-radius: 0 0 10px 10px;
  border: 1px solid #cdcbf7; border-top: none;
}
.problems-grid { border-top: 2px solid #cdcbf7; }
.problem { border-bottom: 1px solid #f3f4f6; font-size: 1.125rem; color: var(--site-text, #1f2937); }

/* ═══ Variant Chip ═══ */
.variant-chip {
  font-size: 0.8rem; font-weight: 600; padding: 0.25rem 0.6rem; border-radius: 999px;
  color: #433bc2; background: #f0f0fc; border: 1px solid #afabf3;
}


/* ═══ Category Cards — Archetype: pill-shape ═══ */

.section-header { margin: 1.5rem 0 1rem; }
.section-header h2 { font-size: 1.5rem; font-weight: 700; color: var(--site-text, #1f2937); font-family: var(--font-heading); }
.section-header p { color: #6b7280; margin-top: 0.25rem; }
.categories-section { padding: 0 0.5rem; }

.categories-grid { display: flex; flex-wrap: wrap; gap: 0.8rem; margin: 1rem 0; justify-content: center; }
.category-card {
  display: flex; flex-direction: column; align-items: center; gap: 0.4rem;
  padding: 1rem 2rem; background: white;
  border: 2px solid #cdcbf7; border-radius: 999px;
  box-shadow: 0 1px 4px rgba(79,70,229,0.06); text-decoration: none; color: inherit;
  text-align: center; transition: all 180ms ease; min-width: 180px;
}
.category-card:hover { border-color: #4f46e5; background: #f7f7fd; box-shadow: 0 4px 12px rgba(79,70,229,0.12); }
.category-icon { font-size: 1.8rem; line-height: 1; }
.category-card h3 { font-weight: 600; font-size: 0.95rem; color: var(--site-text); margin: 0; }
.category-card p { font-size: 0.8rem; color: #6b7280; display: none; }
.category-meta { font-size: 0.8rem; font-weight: 600; color: #4f46e5; }

/* ═══ Subcategory Cards — Archetype: left-accent ═══ */
.subcategories-section { margin: 1.5rem 0; }
.difficulty-icon { font-size: 1.3rem; }

.subcategories-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; }
.subcategory-card {
  display: flex; flex-direction: column; gap: 0.4rem;
  padding: 1.25rem 1rem; background: white;
  border: 2px solid #cdcbf7; border-left: 4px solid #4f46e5;
  border-radius: 6px; text-decoration: none; color: inherit;
  transition: all 180ms ease;
}
.subcategory-card:hover { border-color: #4f46e5; box-shadow: 0 4px 12px rgba(79,70,229,0.12); transform: translateY(-1px); }
.subcategory-card h3 { font-weight: 600; color: var(--site-text); }
.subcategory-card p { font-size: 0.85rem; color: #6b7280; }
.subcategory-arrow { font-size: 0.85rem; font-weight: 600; color: #4f46e5; margin-top: auto; }

/* ═══ Worksheet Grid — Archetype: compact-tile ═══ */
.worksheets-section { margin: 1.5rem 0; }

.worksheets-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 0.75rem; }
.worksheet-card {
  display: flex; flex-direction: column; align-items: center; gap: 0.3rem;
  padding: 1rem; background: white;
  border: 2px solid #cdcbf7; border-radius: 6px;
  text-decoration: none; color: inherit; text-align: center; transition: all 180ms ease;
}
.worksheet-card:hover { border-color: #4f46e5; background: #f7f7fd; }
.worksheet-number { font-weight: 700; font-size: 1.1rem; color: #4f46e5; }
.worksheet-problems { font-size: 0.8rem; color: #9ca3af; }

/* ═══ Content Toggle — Archetype: plus-minus ═══ */

.body-content--collapsible {
  margin: 1rem 0; border: 1px solid #cdcbf7;
  border-radius: 10px; overflow: hidden;
}
.content-toggle { border: none; }

.content-toggle summary {
  padding: 0.9rem 1.25rem; font-weight: 600; font-size: 0.95rem; color: #231f67;
  cursor: pointer; background: #f7f7fd; border-bottom: 1px solid transparent;
  transition: background 150ms ease; list-style: none;
}
.content-toggle summary::-webkit-details-marker { display: none; }
.content-toggle summary::before {
  content: '+'; display: inline-flex; align-items: center; justify-content: center;
  width: 1.2rem; height: 1.2rem; margin-right: 0.6rem; font-size: 1rem; font-weight: 700;
  color: white; background: #4f46e5; border-radius: 50%;
  transition: transform 200ms ease;
}
.content-toggle[open] summary::before { content: '−'; background: #10b981; }
.content-toggle summary:hover { background: #e9e8fb; }
.content-toggle[open] summary { border-bottom-color: #cdcbf7; }
.content-toggle-panel { padding: 1.25rem 1.5rem; }
.content-toggle-panel h2 { font-size: 1.3rem; font-weight: 700; color: #1b1850; margin: 1rem 0 0.5rem; }
.content-toggle-panel h3 { font-size: 1.1rem; font-weight: 600; color: #231f67; margin: 0.75rem 0 0.4rem; }
.content-toggle-panel p { line-height: 1.7; color: #374151; margin: 0.4rem 0; }
.content-toggle-panel ul, .content-toggle-panel ol { padding-left: 1.25rem; margin: 0.5rem 0; color: #374151; }
.content-toggle-panel li { margin: 0.3rem 0; line-height: 1.6; }
.content-toggle-panel strong { color: #1b1850; }


/* ═══ Score Panel — Archetype: progress-bar ═══ */

.score-panel {
  display: none; background: white; border: 1px solid #cdcbf7;
  border-radius: 6px; padding: 1.25rem 1.5rem;
  margin-top: 1rem; transition: all 200ms ease;
}
.score-panel.score-visible { display: block; animation: scoreSlide 300ms ease-out; }
@keyframes scoreSlide { from { opacity: 0; transform: translateX(-20px); } to { opacity: 1; transform: translateX(0); } }
.score-inner { position: relative; }
.score-inner::after {
  content: ""; display: block; height: 6px; margin-top: 0.75rem;
  background: #cdcbf7; border-radius: 3px; overflow: hidden;
}
.score-icon { font-size: 1.5rem; line-height: 1; }
.score-detail { font-size: 1rem; font-weight: 600; color: var(--site-text); }
.score-pct { font-size: 1.6rem; font-weight: 800; color: #4f46e5; font-family: var(--font-heading); }

/* ═══ Content Section ═══ */
.content-section { padding: 1.5rem; margin: 1rem 0; }
.content-section h2 { font-family: var(--font-heading); color: #1b1850; font-weight: 700; margin-bottom: 0.75rem; }
.content-section h3 { color: #231f67; font-weight: 600; }
.content-section p { line-height: 1.7; color: #374151; }


/* ═══ Interactive Answer Input ═══ */
.answer-input {
  border: 2px solid #cdcbf7; border-radius: 4px;
  background: #ffffff; color: var(--site-text, #1f2937);
  font-family: inherit; font-size: 1rem; font-weight: 600;
  transition: border-color 150ms ease, box-shadow 150ms ease;
}
.answer-input:focus {
  border-color: #4f46e5; box-shadow: 0 0 0 3px rgba(79,70,229,0.12);
}

/* Problem states */
.problem.is-correct .answer-input { border-color: #10b981; background: #f0faf7; color: #0c8a60; }
.problem.is-wrong .answer-input { border-color: #ef4444; background: #fef2f2; color: #991b1b; }
.problem.is-empty .answer-input { border-color: #f59e0b; background: #fffbeb; }
.problem.is-correct { border-left-color: #10b981 !important; }
.problem.is-wrong { border-left-color: #ef4444 !important; }

/* Problem hover */
.problem { transition: transform 180ms ease, box-shadow 180ms ease; }
.problem:hover { transform: translateX(2px); }

/* Problem number badge */
.problem .num {
  background: #f0f0fc; color: #4f46e5;
  font-weight: 700; font-family: var(--font-heading);
}

/* Answer badge */
.problem .answer {
  background: #e7f8f2; color: #0c8a60;
  font-weight: 700; border-radius: 4px;
}

/* ═══ Score Retry Button ═══ */
.score-retry {
  background: #f0f0fc; color: #4f46e5;
  border: 2px solid #afabf3; cursor: pointer;
  transition: all 150ms ease;
}
.score-retry:hover {
  background: #4f46e5; color: white; border-color: #433bc2;
}

/* ═══ Utility Animations ═══ */
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes slideUp { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }
.fade-in { animation: fadeIn 300ms ease-out; }
.slide-up { animation: slideUp 300ms ease-out; }


/* ═══ SEO Components — Archetype: gradient-fill ═══ */
/* hover=scale, grid=2col-auto, palette=monochrome */

.seo-components { margin: 1.5rem 0; }
.seo-components--primary { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.4rem; }
.seo-components--secondary { margin-top: 1rem; }
.seo-more-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 1.4rem; }

.seo-block {
  background: linear-gradient(135deg, #f2f2fd 0%, #e9e8fb 100%);
  border: 1px solid #b8b5f4;
  border-radius: 6px;
  padding: 1.15rem 1.25rem;
  box-shadow: 0 1px 3px rgba(79,70,229,0.06);
  transition: box-shadow 200ms ease, transform 200ms ease;
}
.seo-block:hover { transform: scale(1.02); }

/* -- SEO Card -- header-band accent -- */
.seo-card {
  background: var(--site-background, #ffffff);
  border-color: var(--site-border, #e5e7eb);
  border-top: none;
}

.seo-card::before {
  background: var(--site-primary, #3b82f6);
}

.seo-card:hover {
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--site-primary, #3b82f6) 15%, transparent);
}

/* Card band color per SEO type */
.seo-card.features::before  { background: var(--site-primary, #3b82f6); }
.seo-card.benefits::before  { background: var(--site-accent, #10b981); }
.seo-card.faq::before       { background: var(--site-primary-dark, #1d4ed8); }
.seo-card.tips::before      { background: #f59e0b; }
.seo-card.steps::before     { background: var(--site-accent-hover, #059669); }
.seo-card.tutorial::before  { background: var(--site-accent, #10b981); }
.seo-card.examples::before  { background: #06b6d4; }
.seo-card.use-cases::before { background: #ec4899; }
.seo-card.common-mistakes::before { background: #ef4444; }
.seo-card.practice::before  { background: #f97316; }
.seo-card.requirements::before { background: #6366f1; }
.seo-card.resources::before { background: #14b8a6; }
.seo-card.next-steps::before { background: var(--site-primary, #3b82f6); }
.seo-card.summary::before   { background: #64748b; }
.seo-card.related::before   { background: #a855f7; }



.seo-components--secondary .seo-block { background: #f7f7fd; }
.seo-block.tutorial { border-left: 3px solid #4e46e5; }
.seo-block.examples { border-left: 3px solid #ae46e5; }
.seo-block.use-cases { border-left: 3px solid #e546bc; }
.seo-block.common-mistakes { border-left: 3px solid #e5465c; }
.seo-block.practice { border-left: 3px solid #e58e46; }
.seo-block.requirements { border-left: 3px solid #dbe546; }
.seo-block.resources { border-left: 3px solid #7ce546; }
.seo-block.next-steps { border-left: 3px solid #46e56e; }
.seo-block.summary { border-left: 3px solid #46e5ce; }
.seo-block.related { border-left: 3px solid #469ce5; }

/* ── SEO block typography ── */
.seo-block h2 { font-size: 1.15rem; font-weight: 700; color: #1b1850; margin: 0 0 0.6rem; font-family: var(--font-heading); }
.seo-block h3 { font-size: 1rem; font-weight: 600; color: #231f67; margin: 0.6rem 0 0.4rem; }
.seo-block h4 { font-size: 0.95rem; font-weight: 600; color: #2b267d; margin: 0.5rem 0 0.3rem; }
.seo-block p { font-size: 0.92rem; line-height: 1.65; color: #374151; margin: 0.35rem 0; }
.seo-block ul, .seo-block ol { padding-left: 1.2rem; margin: 0.4rem 0; }
.seo-block li { font-size: 0.92rem; line-height: 1.55; color: #374151; margin: 0.25rem 0; }
.seo-block strong { color: #1b1850; }
.seo-block a { color: #4f46e5; text-decoration: none; }
.seo-block a:hover { text-decoration: underline; }

/* ── FAQ details ── */
.seo-block details { border-bottom: 1px solid #d3d0f8; padding: 0.5rem 0; }
.seo-block details:last-child { border-bottom: none; }
.seo-block details summary { font-weight: 600; font-size: 0.92rem; cursor: pointer; list-style: none; color: #231f67; }
.seo-block details summary::-webkit-details-marker { display: none; }
.seo-block details summary::before { content: "▸"; margin-right: 0.4rem; color: #4f46e5; display: inline-block; transition: transform 150ms ease; }
.seo-block details[open] summary::before { transform: rotate(90deg); }
.seo-block details p { padding: 0.3rem 0 0.3rem 1rem; color: #4b5563; font-size: 0.88rem; }


/* ═══ Page Navigation ═══ */
.page-navigation {
  display: flex; justify-content: space-between; align-items: center; gap: 0.5rem;
  margin-top: 1.5rem; padding: 1rem; background: white;
  border: 1px solid #cdcbf7; border-radius: 10px;
  box-shadow: 0 1px 3px rgba(79,70,229,0.06);
}
.btn-nav {
  display: inline-flex; align-items: center; padding: 0.5rem 1rem;
  border-radius: 4px; color: #4f46e5;
  text-decoration: none; font-weight: 500; font-size: 0.95rem; transition: background 150ms ease;
}
.btn-nav:hover { background: #f7f7fd; }
.btn-nav.disabled { color: #d1d5db; cursor: not-allowed; }


/* ═══ Print Styles ═══ */
/* Removed: all print rules are now consolidated in platform layer:
   - print-base.css (dedicated print route)
   - main.css @media print (browser Ctrl+P path)
   - print-profile-*.css (site-type-specific density) */


/* ═══ Responsive ═══ */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.8rem; }
  .hero .subtitle { max-width: 100%; }
  .hero-stats { gap: 1.2rem; }
  .stat-number { font-size: 1.3rem; }
  .hero::after { display: none; }
  .categories-grid { gap: 0.5rem; } .category-card { min-width: 140px; padding: 0.75rem 1.2rem; }
  .subcategories-grid { grid-template-columns: 1fr; }
  .worksheets-grid { grid-template-columns: repeat(auto-fit, minmax(100px, 1fr)); }
  .seo-components--primary { grid-template-columns: 1fr; }
  .seo-more-grid { grid-template-columns: 1fr; }
  .page-navigation { flex-wrap: wrap; justify-content: center; }
}

@media (max-width: 480px) {
  .hero { padding: 1.5rem 1rem; }
  .hero h1 { font-size: 1.5rem; }
  .hero-stats { flex-direction: column; gap: 0.8rem; }
  .categories-grid { grid-template-columns: 1fr; }
  .subcategories-grid { grid-template-columns: 1fr; }
}