/* =========================================================
   신동영T 통합과학 연구소 - 공통 스타일
   디자인 방향: 흰 배경 · 얇은 선 · 짙은 남색 포인트 · 심플
   ========================================================= */

/* ---------- 폰트 (Pretendard - 한국어 웹 최적화) ---------- */
@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/variable/pretendardvariable-dynamic-subset.css');

/* ---------- 리셋 ---------- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* ---------- 색상·치수 변수 (한 곳에서 전체 디자인 제어) ---------- */
:root {
  --color-primary: #0a2540;         /* 짙은 남색 (메인 포인트) */
  --color-primary-soft: #1a3a5c;    /* hover용 약간 밝은 남색 */
  --color-text: #1a1a1a;            /* 본문 글자 */
  --color-text-muted: #6b6b6b;      /* 보조 글자 */
  --color-border: #e8e8e8;          /* 얇은 선 */
  --color-bg: #ffffff;              /* 배경 (흰색) */
  --color-bg-subtle: #fafafa;       /* 살짝 어두운 배경 (구역 구분용) */

  --max-width: 1100px;
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 2rem;
  --space-lg: 4rem;
  --space-xl: 6rem;

  --font-sans: 'Pretendard Variable', Pretendard, -apple-system, BlinkMacSystemFont,
               'Apple SD Gothic Neo', 'Malgun Gothic', sans-serif;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.15s;
}
a:hover { color: var(--color-primary-soft); }

img { max-width: 100%; display: block; }

/* ---------- 레이아웃 컨테이너 ---------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ---------- 헤더 ---------- */
.site-header {
  border-bottom: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 100;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1.25rem;
  padding-bottom: 1.25rem;
}
.site-logo {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: -0.02em;
}
.site-logo:hover { color: var(--color-primary-soft); }
.site-nav {
  display: flex;
  gap: 2rem;
  list-style: none;
}
.site-nav a {
  color: var(--color-text);
  font-size: 0.95rem;
  font-weight: 500;
  position: relative;
  padding: 0.25rem 0;
}
.site-nav a:hover { color: var(--color-primary); }
.site-nav a.active {
  color: var(--color-primary);
  font-weight: 600;
}
.site-nav a.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-primary);
}

/* 모바일 메뉴 토글 버튼 */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  font-size: 1.5rem;
  color: var(--color-primary);
}

/* ---------- 히어로 (홈 첫 화면) ---------- */
.hero {
  padding: var(--space-xl) 0 var(--space-lg);
  border-bottom: 1px solid var(--color-border);
  position: relative;
  overflow: hidden;
}
.hero-content {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: var(--space-lg);
  align-items: center;
}
.hero-text .eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--color-primary);
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-primary);
}
.hero-text h1 {
  font-size: clamp(2rem, 4.5vw, 3.25rem);
  font-weight: 800;
  color: var(--color-primary);
  letter-spacing: -0.035em;
  line-height: 1.15;
  margin-bottom: 1.25rem;
}
.hero-text .lead {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
  max-width: 32ch;
}
.hero-cta-group {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* 상승 곡선 그래픽 (슬로건의 시각적 메타포) */
.hero-graphic {
  position: relative;
  height: 280px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.hero-graphic svg {
  width: 100%;
  height: 100%;
}

/* ---------- 버튼 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  background: var(--color-primary);
  color: white;
  border-radius: 4px;
  font-weight: 500;
  font-size: 0.95rem;
  font-family: inherit;
  border: 1px solid var(--color-primary);
  cursor: pointer;
  transition: all 0.15s;
}
.btn:hover {
  background: var(--color-primary-soft);
  border-color: var(--color-primary-soft);
  color: white;
}
.btn-outline {
  background: transparent;
  color: var(--color-primary);
}
.btn-outline:hover {
  background: var(--color-primary);
  color: white;
}

/* ---------- 페이지 헤더 (홈이 아닌 페이지 상단) ---------- */
.page-header {
  padding: var(--space-lg) 0 var(--space-md);
  border-bottom: 1px solid var(--color-border);
}
.page-header .eyebrow {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--color-primary);
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}
.page-header h1 {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: -0.025em;
  line-height: 1.2;
}
.page-header .subtitle {
  margin-top: 0.75rem;
  color: var(--color-text-muted);
  max-width: 60ch;
}

/* ---------- 섹션 ---------- */
section {
  padding: var(--space-lg) 0;
}
section + section {
  border-top: 1px solid var(--color-border);
}
section h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}
section h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-text);
}
section p {
  margin-bottom: var(--space-sm);
  color: var(--color-text);
}
section p.muted { color: var(--color-text-muted); }

/* ---------- 2단 컬럼 ---------- */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

/* ---------- 카드 그리드 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}
.card {
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: var(--color-bg);
  transition: border-color 0.15s, transform 0.15s;
}
.card:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}
.card .meta {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 0.5rem;
  display: flex;
  gap: 0.75rem;
  align-items: center;
}
.card .tag {
  display: inline-block;
  padding: 0.15rem 0.6rem;
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  font-size: 0.75rem;
  color: var(--color-primary);
  font-weight: 500;
}
.card h3 {
  color: var(--color-text);
  margin-bottom: 0.5rem;
}
.card p {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  margin-bottom: 1rem;
}
.card .card-action {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-primary);
}
.card .card-action::after {
  content: ' →';
  transition: transform 0.15s;
  display: inline-block;
}
.card:hover .card-action::after {
  transform: translateX(3px);
}

/* ---------- 강의 정보 박스 (시간표 페이지) ---------- */
.subject-box {
  padding: 2rem;
  border: 1px solid var(--color-border);
  border-radius: 8px;
}
.subject-box .subject-label {
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-primary);
  font-weight: 600;
  margin-bottom: 0.5rem;
}
.subject-box h3 {
  font-size: 1.35rem;
  color: var(--color-primary);
  margin-bottom: 0.5rem;
}
.subject-box .target {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  margin-bottom: 1.25rem;
}
.subject-box ul {
  list-style: none;
  padding: 0;
}
.subject-box li {
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 0.95rem;
}
.subject-box li:last-child { border-bottom: none; }

/* ---------- 시간표 ---------- */
.schedule-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: var(--space-sm);
  font-size: 0.95rem;
}
.schedule-table th,
.schedule-table td {
  padding: 0.875rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}
.schedule-table th {
  font-weight: 600;
  color: var(--color-primary);
  background: var(--color-bg-subtle);
  font-size: 0.85rem;
  letter-spacing: 0.02em;
}

/* ---------- 출강지역 ---------- */
.region-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}
.region-card {
  padding: 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  text-align: center;
}
.region-card .region-name {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}
.region-card .region-info {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* ---------- 필터 (학습자료실) ---------- */
.filter-bar {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--color-border);
}
.filter-btn {
  padding: 0.5rem 1rem;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  font-size: 0.875rem;
  color: var(--color-text-muted);
  cursor: pointer;
  font-family: inherit;
  transition: all 0.15s;
}
.filter-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.filter-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: white;
}

/* ---------- 블로그 포스트 리스트 ---------- */
.post-list {
  list-style: none;
}
.post-item {
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--color-border);
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: var(--space-md);
  align-items: baseline;
}
.post-item:first-child { padding-top: 0; }
.post-item:last-child { border-bottom: none; }
.post-date {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  font-variant-numeric: tabular-nums;
}
.post-content h3 {
  font-size: 1.15rem;
  margin-bottom: 0.35rem;
}
.post-content h3 a {
  color: var(--color-text);
}
.post-content h3 a:hover { color: var(--color-primary); }
.post-content .excerpt {
  font-size: 0.95rem;
  color: var(--color-text-muted);
}
.post-content .tag {
  display: inline-block;
  font-size: 0.75rem;
  padding: 0.1rem 0.55rem;
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  color: var(--color-primary);
  margin-bottom: 0.4rem;
  font-weight: 500;
}

/* ---------- 푸터 ---------- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) 0 var(--space-md);
  margin-top: var(--space-xl);
  background: var(--color-bg-subtle);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}
.footer-grid h4 {
  color: var(--color-primary);
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}
.footer-grid p,
.footer-grid a,
.footer-grid li {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  line-height: 1.8;
  list-style: none;
}
.footer-grid a:hover { color: var(--color-primary); }
.site-footer .copyright {
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
  font-size: 0.85rem;
  color: var(--color-text-muted);
  text-align: center;
}

/* ---------- 반응형 (모바일 768px 이하) ---------- */
@media (max-width: 768px) {
  .hero-content {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
  .hero-graphic { height: 200px; }
  .two-col { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .post-item {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }
}

@media (max-width: 720px) {
  .menu-toggle { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: 1rem var(--space-md);
    gap: 0;
  }
  .site-nav.open { display: flex; }
  .site-nav a {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--color-border);
    width: 100%;
  }
  .site-nav a:last-child { border-bottom: none; }
}