/* ==========================================================================
   Haegyung × Oxygen 6 Design Tokens & Component Recipes
   Source: 2026-09-22 Context Lens (Warm Paper / Petrol Teal / Burnt Sienna)
   ========================================================================== */

:root {
  /* 1. Surfaces & Canvas */
  --hg-color-surface: #F9F8F6;          /* Warm Paper */
  --hg-color-surface-card: #FFFFFF;     /* Pure Card Surface */
  --hg-color-surface-soft: #F2EFE9;     /* Soft Inset / Worksheet */
  --hg-color-surface-dark: #121518;     /* Dark Canvas */
  --hg-color-surface-dark-card: #1B1F23;/* Dark Card Surface */

  /* 2. Inks & Typography */
  --hg-color-ink: #1F2428;              /* Graphite Primary */
  --hg-color-ink-muted: #5C646C;        /* Secondary Caption */
  --hg-color-ink-light: #F9F8F6;        /* Inverse Ink */
  --hg-color-line: #E2DDD5;             /* Hairline Border */
  --hg-color-line-dark: #2D3339;        /* Dark Hairline */

  /* 3. Semantic Pigments (Brand & Judgment Vectors) */
  --hg-color-primary: #134E5E;          /* Petrol Teal (맥락 렌즈 / 코어 안료) */
  --hg-color-accent: #C85A32;           /* Burnt Sienna (미세 강조 / 닻) */
  --hg-color-problem: #134E5E;          /* 질문 / 문제 정의 (Petrol Teal) */
  --hg-color-evidence: #2D6A4F;         /* 근거 / 출처 (Forest Green) */
  --hg-color-control: #B07D1C;          /* 경계 / 비주장 패널 (Warm Ochre) */
  --hg-color-action: #1F2428;           /* 실행 / 주 CTA (Graphite) */
  --hg-color-transfer: #6B7280;         /* 전이 / 다음 생각 (Slate Grey) */

  /* 4. Font Families */
  --hg-font-body: -apple-system, BlinkMacSystemFont, "Pretendard", "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  --hg-font-heading: "Noto Serif KR", Georgia, "Times New Roman", serif;
  --hg-font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  /* 5. Typography Scales */
  --hg-text-xs: 0.75rem;                /* 12px */
  --hg-text-small: 0.84375rem;          /* 13.5px */
  --hg-text-body: 1rem;                 /* 16px */
  --hg-text-md: 1.125rem;               /* 18px */
  --hg-text-lg: 1.3125rem;              /* 21px */
  --hg-text-h2: clamp(1.5rem, 2.8vw, 2.25rem);
  --hg-text-h1: clamp(2.25rem, 4.5vw, 3.75rem);

  --hg-leading-body: 1.78;
  --hg-leading-snug: 1.35;
  --hg-leading-tight: 1.15;

  /* 6. Spacing Scale */
  --hg-space-1: 0.25rem;                /* 4px */
  --hg-space-2: 0.5rem;                 /* 8px */
  --hg-space-3: 0.75rem;                /* 12px */
  --hg-space-4: 1rem;                   /* 16px */
  --hg-space-5: 1.5rem;                 /* 24px */
  --hg-space-6: 2rem;                   /* 32px */
  --hg-space-7: 3rem;                   /* 48px */
  --hg-space-8: 4.5rem;                 /* 72px */
  --hg-space-9: 6.5rem;                 /* 104px */

  /* 7. Layout Boundaries */
  --hg-content-max: 44rem;              /* 704px 최적 독해 폭 */
  --hg-page-max: 76rem;                 /* 1216px 전체 그리드 폭 */
  --hg-rail-width: 14rem;               /* 224px 좌우 레일 폭 */

  /* 8. Shapes & Elevations */
  --hg-radius-sm: 0.25rem;              /* 4px */
  --hg-radius-md: 0.5rem;               /* 8px */
  --hg-border-width: 1px;
  --hg-focus-ring: 0 0 0 3px color-mix(in srgb, var(--hg-color-primary) 30%, transparent);
  --hg-motion-fast: 160ms cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme="dark"], body.dark-mode {
  --hg-color-surface: var(--hg-color-surface-dark);
  --hg-color-surface-card: var(--hg-color-surface-dark-card);
  --hg-color-surface-soft: #181C20;
  --hg-color-ink: #F0EDE6;
  --hg-color-ink-muted: #9BA3AF;
  --hg-color-line: var(--hg-color-line-dark);
  --hg-color-primary: #38BDF8;
  --hg-color-accent: #FB923C;
  --hg-color-problem: #38BDF8;
  --hg-color-evidence: #34D399;
  --hg-color-control: #FBBF24;
  --hg-color-action: #F9F8F6;
  --hg-color-transfer: #9CA3AF;
}

.hg-shell {
  background-color: var(--hg-color-surface);
  color: var(--hg-color-ink);
  font-family: var(--hg-font-body);
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  margin: 0;
  padding: 0;
}

.hg-header {
  border-bottom: var(--hg-border-width) solid var(--hg-color-line);
  padding: var(--hg-space-4) var(--hg-space-6);
  position: sticky;
  top: 0;
  background-color: color-mix(in srgb, var(--hg-color-surface) 92%, transparent);
  backdrop-filter: blur(8px);
  z-index: 100;
}

.hg-nav-inner {
  max-width: var(--hg-page-max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.hg-brand-logo {
  display: inline-flex;
  align-items: center;
  gap: var(--hg-space-3);
  text-decoration: none;
}

.hg-symbol-icon {
  width: 28px;
  height: 28px;
  display: inline-block;
  flex-shrink: 0;
  vertical-align: middle;
}

.hg-wordmark {
  font-family: var(--hg-font-heading);
  font-size: var(--hg-text-lg);
  font-weight: 700;
  color: var(--hg-color-ink);
  letter-spacing: -0.01em;
  line-height: 1;
}

.hg-nav-links {
  display: flex;
  gap: var(--hg-space-5);
  list-style: none;
  margin: 0;
  padding: 0;
}

.hg-nav-link {
  color: var(--hg-color-ink-muted);
  text-decoration: none;
  font-size: var(--hg-text-small);
  font-weight: 500;
  transition: color var(--hg-motion-fast);
}

.hg-nav-link:hover, .hg-nav-link.active {
  color: var(--hg-color-primary);
}

.hg-section {
  padding-block: var(--hg-space-8);
  border-bottom: var(--hg-border-width) solid var(--hg-color-line);
}

.hg-container {
  max-width: var(--hg-page-max);
  margin: 0 auto;
  padding-inline: var(--hg-space-6);
}

.hg-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
  gap: var(--hg-space-7);
  align-items: center;
}

.hg-eyebrow {
  display: inline-block;
  color: var(--hg-color-primary);
  font-size: var(--hg-text-small);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: var(--hg-space-3);
}

.hg-title-hero {
  font-family: var(--hg-font-heading);
  font-size: var(--hg-text-h1);
  line-height: var(--hg-leading-tight);
  color: var(--hg-color-ink);
  letter-spacing: -0.02em;
  margin: 0 0 var(--hg-space-5) 0;
  word-break: keep-all;
}

.hg-lead {
  font-size: var(--hg-text-md);
  line-height: var(--hg-leading-body);
  color: var(--hg-color-ink-muted);
  margin-bottom: var(--hg-space-6);
  word-break: keep-all;
}

.hg-rails-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--hg-space-6);
  margin-top: var(--hg-space-6);
}

.hg-worksheet-card {
  background-color: var(--hg-color-surface-card);
  border: var(--hg-border-width) solid var(--hg-color-line);
  border-radius: var(--hg-radius-md);
  padding: var(--hg-space-6);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform var(--hg-motion-fast), border-color var(--hg-motion-fast);
}

.hg-worksheet-card:hover {
  border-color: var(--hg-color-primary);
  transform: translateY(-2px);
}

.hg-card-tag {
  font-size: var(--hg-text-xs);
  font-weight: 700;
  color: var(--hg-color-accent);
  margin-bottom: var(--hg-space-2);
}

.hg-card-title {
  font-family: var(--hg-font-heading);
  font-size: var(--hg-text-lg);
  font-weight: 600;
  color: var(--hg-color-ink);
  margin: 0 0 var(--hg-space-3) 0;
}

.hg-card-desc {
  font-size: var(--hg-text-small);
  line-height: var(--hg-leading-body);
  color: var(--hg-color-ink-muted);
  margin: 0 0 var(--hg-space-5) 0;
}

.hg-reading-grid {
  display: grid;
  grid-template-columns: var(--hg-rail-width) minmax(0, var(--hg-content-max)) var(--hg-rail-width);
  gap: var(--hg-space-6);
  justify-content: center;
}

.hg-orientation-rail {
  font-size: var(--hg-text-small);
  color: var(--hg-color-ink-muted);
  border-right: var(--hg-border-width) solid var(--hg-color-line);
  padding-right: var(--hg-space-4);
  position: sticky;
  top: 5rem;
  align-self: start;
}

.hg-prose {
  font-size: var(--hg-text-body);
  line-height: var(--hg-leading-body);
  color: var(--hg-color-ink);
  word-break: keep-all;
  overflow-wrap: anywhere;
}

.hg-prose p {
  margin-bottom: var(--hg-space-5);
}

.hg-prose h2 {
  font-family: var(--hg-font-heading);
  font-size: var(--hg-text-h2);
  line-height: var(--hg-leading-snug);
  margin-top: var(--hg-space-7);
  margin-bottom: var(--hg-space-4);
}

.hg-judgment-rail {
  border-left: var(--hg-border-width) solid var(--hg-color-line);
  padding-left: var(--hg-space-4);
  position: sticky;
  top: 5rem;
  align-self: start;
}

.hg-vector-item {
  padding: var(--hg-space-3) var(--hg-space-3);
  margin-bottom: var(--hg-space-3);
  border-left: 3px solid transparent;
  font-size: var(--hg-text-small);
}

.hg-vector--problem { border-color: var(--hg-color-problem); background: color-mix(in srgb, var(--hg-color-problem) 6%, transparent); }
.hg-vector--evidence { border-color: var(--hg-color-evidence); background: color-mix(in srgb, var(--hg-color-evidence) 6%, transparent); }
.hg-vector--control { border-color: var(--hg-color-control); background: color-mix(in srgb, var(--hg-color-control) 6%, transparent); }
.hg-vector--action { border-color: var(--hg-color-action); background: color-mix(in srgb, var(--hg-color-action) 6%, transparent); }
.hg-vector--transfer { border-color: var(--hg-color-transfer); background: color-mix(in srgb, var(--hg-color-transfer) 6%, transparent); }

a:focus-visible, button:focus-visible, input:focus-visible {
  box-shadow: var(--hg-focus-ring);
  outline: 2px solid var(--hg-color-primary);
  outline-offset: 2px;
}

.hg-cta-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--hg-color-primary);
  color: #FFFFFF;
  font-size: var(--hg-text-small);
  font-weight: 600;
  min-height: 44px;
  padding: var(--hg-space-2) var(--hg-space-5);
  border-radius: var(--hg-radius-sm);
  border: 1px solid var(--hg-color-primary);
  text-decoration: none;
  cursor: pointer;
  transition: opacity var(--hg-motion-fast), background-color var(--hg-motion-fast);
}

.hg-cta-primary:hover {
  opacity: 0.92;
}

.hg-cta-primary:focus-visible {
  box-shadow: var(--hg-focus-ring);
  outline: none;
}

.hg-link-secondary {
  color: var(--hg-color-primary);
  font-size: var(--hg-text-small);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 4px;
  display: inline-flex;
  align-items: center;
  min-height: 36px;
}

.hg-footer {
  padding-block: var(--hg-space-8);
  background-color: var(--hg-color-surface-soft);
  color: var(--hg-color-ink-muted);
  font-size: var(--hg-text-small);
}

.hg-footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--hg-space-6);
}

@media (max-width: 1024px) {
  .hg-reading-grid {
    grid-template-columns: minmax(0, 1fr);
  }
  .hg-orientation-rail, .hg-judgment-rail {
    position: static;
    border: none;
    padding: 0;
  }
  .hg-hero-grid {
    grid-template-columns: minmax(0, 1fr);
  }
  .hg-rails-grid {
    grid-template-columns: minmax(0, 1fr);
  }
  .hg-footer-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

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