/* ============================================================
   Yuja EDU Design Tokens v2 (Lemon Refresh)
   기준 문서: student/DESIGN.md
   모든 배움터 페이지가 이 파일 하나를 참조한다.
   <link rel="stylesheet" href="../shared/yuja-tokens.css">
   ============================================================ */

:root {
  /* Yuja Lemon System (Primary) */
  --color-yuja-lemon: #FFE135;
  --color-yuja-lemon-amber: #F5C800;
  --color-yuja-forest: #142814;
  --color-yuja-forest-mid: #1E3D1E;
  --color-yuja-lemon-tint: #FEFCE8;

  /* Leaf Green Points (Secondary) */
  --color-leaf-green: #4CAA48;
  --color-leaf-green-mid: #388E3C;
  --color-leaf-green-deep: #2D7A29;
  --color-leaf-green-light: #B8E0B5;
  --color-leaf-green-tint: #E8F5E7;

  /* Notion Canvas */
  --color-canvas: #FFFFFF;
  --color-canvas-cream: #F7F6F3;
  --color-surface: #F1F0EE;
  --color-surface-soft: #F8F7F5;
  --color-hairline: #E8E7E4;
  --color-hairline-strong: #D3D1CB;

  /* Text */
  --color-ink-deep: #1A1A1A;
  --color-ink: #37352F;
  --color-charcoal: #4B4945;
  --color-slate: #6F6E69;
  --color-steel: #9B9A97;
  --color-on-dark: #FFFFFF;
  --color-on-dark-muted: rgba(255, 255, 255, 0.70);

  /* Semantic */
  --color-success: #0F7B5C;
  --color-warning: #E67E22;
  --color-error: #C82014;

  /* Radius */
  --radius-xs: 4px;
  --radius-sm: 6px;
  --radius-md: 8px;      /* inputs, secondary buttons (Notion) */
  --radius-lg: 12px;     /* all cards */
  --radius-xl: 16px;
  --radius-full: 9999px; /* primary CTA buttons (Starbucks) */

  /* Button interaction (Starbucks) */
  --btn-press-scale: scale(0.95);
  --btn-height-pill: 50px;
  --btn-height-frap: 56px;

  /* Shadows */
  --shadow-subtle: rgba(15, 15, 15, 0.04) 0px 1px 2px;
  --shadow-card: rgba(15, 15, 15, 0.08) 0px 4px 12px 0px;
  --shadow-mockup: rgba(15, 15, 15, 0.18) 0px 20px 40px -8px;
  --shadow-modal: rgba(15, 15, 15, 0.14) 0px 14px 40px -8px;
  --shadow-frap: 0 0 6px rgba(0, 0, 0, 0.24), 0 8px 12px rgba(0, 0, 0, 0.14);

  /* Typography */
  --font-primary: "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-serif: "Noto Serif KR", "Malgun Gothic", serif;
  --font-mono: "JetBrains Mono", "Courier New", monospace;
  --letter-spacing-normal: -0.01em;
  --letter-spacing-display: -1.5px;
}

/* ============================================================
   공용 컴포넌트 (yj- prefix — 기존 페이지 클래스와 충돌 방지)
   ============================================================ */

/* --- 주 CTA: 풀-필 앰버 버튼 --- */
.yj-btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: var(--btn-height-pill);
  padding: 14px 28px;
  background: var(--color-yuja-lemon-amber);
  color: var(--color-ink-deep);
  font-family: var(--font-primary);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: var(--letter-spacing-normal);
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: transform 150ms ease, filter 150ms ease;
}
.yj-btn-primary:hover { filter: brightness(1.05); }
.yj-btn-primary:active { transform: var(--btn-press-scale); }

/* --- 세컨더리: Notion 8px 아웃라인 --- */
.yj-btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  background: transparent;
  color: var(--color-ink);
  font-family: var(--font-primary);
  font-size: 14px;
  font-weight: 500;
  border: 1px solid var(--color-hairline-strong);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background 150ms ease;
}
.yj-btn-secondary:hover { background: var(--color-surface); }

/* --- 다크 배경 위 화이트 필 버튼 --- */
.yj-btn-on-dark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: var(--btn-height-pill);
  padding: 14px 28px;
  background: var(--color-on-dark);
  color: var(--color-yuja-forest);
  font-family: var(--font-primary);
  font-size: 14px;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: transform 150ms ease;
}
.yj-btn-on-dark:active { transform: var(--btn-press-scale); }

/* --- 카드 --- */
.yj-card {
  background: var(--color-canvas);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

/* --- 뱃지 --- */
.yj-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  background: var(--color-leaf-green);
  color: #FFFFFF;
  font-family: var(--font-primary);
  font-size: 13px;
  font-weight: 600;
  border-radius: var(--radius-full);
}

/* --- 공통 토스트 (복사 성공 등) --- */
.yj-toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--color-yuja-forest);
  color: var(--color-on-dark);
  font-family: var(--font-primary);
  font-size: 15px;
  font-weight: 500;
  padding: 14px 24px;
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-frap);
  opacity: 0;
  pointer-events: none;
  transition: opacity 200ms ease, transform 200ms ease;
  z-index: 9500;
}
.yj-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* --- Forest 푸터 --- */
.yj-footer {
  background: var(--color-yuja-forest);
  color: var(--color-on-dark-muted);
  font-family: var(--font-primary);
  font-size: 14px;
  letter-spacing: var(--letter-spacing-normal);
  padding: 48px 32px;
  text-align: center;
}
.yj-footer a {
  color: var(--color-yuja-lemon);
  text-decoration: none;
  font-weight: 500;
}
.yj-footer a:hover { text-decoration: underline; }
.yj-footer .yj-footer-brand {
  color: var(--color-on-dark);
  font-weight: 700;
  font-size: 16px;
  margin-bottom: 8px;
}