/* ==========================================================================
 * BBL 포스트 공통 스타일
 * - 글 페이지(posts/*.html)와 블로그 목록(blog.html)이 공유
 * - index.html의 디자인 토큰과 완전히 동일하게 맞춤
 * ========================================================================== */

/* ===== RESET ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; -webkit-text-size-adjust: 100%; }
body {
  font-family: 'Noto Sans KR', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  color: #d8d8e2;
  background: #08080c;
  line-height: 1.75;
  font-weight: 400;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }

/* ===== VARIABLES ===== */
:root {
  --primary: #2563EB;
  --primary-dark: #1d4ed8;
  --accent: #3b82f6;
  --accent-glow: rgba(37, 99, 235, 0.2);
  --warm: #60a5fa;
  --dark-bg: #08080c;
  --card-bg: #111118;
  --card-bg-hover: #16161e;
  --card-border: rgba(255,255,255,0.08);
  --text-primary: #ffffff;
  --text-secondary: #c8c8d8;
  --text-muted: #8e8ea2;
  --gradient-hero: linear-gradient(160deg, #08080c 0%, #0a0f1a 40%, #0c1222 100%);
  --max-width: 1200px;

  /* 테마 전환용 추가 변수 */
  --nav-bg-scrolled: rgba(8,8,12,0.94);
  --overlay-bg-heavy: rgba(8,8,12,0.98);
  --footer-bg: #050508;
  --blog-list-bg: #0a0a10;
  --post-cta-bg: linear-gradient(135deg, rgba(37,99,235,0.1), rgba(59,130,246,0.05));
  --post-cta-border: rgba(37,99,235,0.2);
  --blockquote-bg: rgba(37,99,235,0.06);
  --code-bg: rgba(255,255,255,0.06);
  --figure-caption-bg: rgba(0,0,0,0.3);
  --table-header-bg: rgba(37,99,235,0.1);
}

/* ===== 라이트 모드 오버라이드 ===== */
:root[data-theme="light"] {
  --dark-bg: #ffffff;
  --card-bg: #ffffff;
  --card-bg-hover: #f7f7fa;
  --card-border: rgba(10,10,30,0.10);
  --text-primary: #0a0a14;
  --text-secondary: #2d2d3a;
  --text-muted: #5a5a6e;
  --gradient-hero: linear-gradient(160deg, #ffffff 0%, #f5f7fb 40%, #eaf0f8 100%);

  --nav-bg-scrolled: rgba(255,255,255,0.94);
  --overlay-bg-heavy: rgba(255,255,255,0.98);
  --footer-bg: #f2f3f7;
  --blog-list-bg: #f8f9fc;
  --post-cta-bg: linear-gradient(135deg, rgba(37,99,235,0.08), rgba(59,130,246,0.04));
  --post-cta-border: rgba(37,99,235,0.25);
  --blockquote-bg: rgba(37,99,235,0.05);
  --code-bg: rgba(10,10,30,0.06);
  --figure-caption-bg: rgba(10,10,30,0.04);
  --table-header-bg: rgba(37,99,235,0.08);
  --accent-glow: rgba(37, 99, 235, 0.15);
}

/* 테마 전환 부드럽게 */
html, body, nav, footer, section, article, .blog-card, .latest-note-card,
.post-article, .post-cta, .post-body, .blog-hero, .blog-list-wrap,
.blog-filter-wrap, .filter-btn, .post-category, .blog-card-category,
input, textarea, select, button {
  transition: background-color 0.25s ease, border-color 0.25s ease, color 0.25s ease;
}

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ===== NAV (index.html과 동일) ===== */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  padding: 14px 0; transition: all 0.4s ease;
  background: var(--nav-bg-scrolled);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid var(--card-border);
}
.nav.scrolled { padding: 12px 0; }
.nav .container { display: flex; align-items: center; justify-content: space-between; }
.nav-logo {
  font-family: 'Inter', sans-serif;
  font-size: 1.5rem; font-weight: 800; color: var(--text-primary);
  display: flex; align-items: baseline; gap: 10px; letter-spacing: -0.5px;
}
.nav-logo-brand {
  font-family: 'Inter', sans-serif;
  font-size: 1.75rem; font-weight: 900; letter-spacing: -1px;
  color: var(--text-primary);
}
.nav-logo-blue { color: var(--primary); }
.nav-logo-sub {
  font-family: 'Noto Sans KR', sans-serif;
  font-size: 0.7rem; color: var(--text-muted); font-weight: 500;
  letter-spacing: 0.3px;
}
.nav-links { display: flex; gap: 28px; align-items: center; }
.nav-links a {
  font-size: 0.92rem; font-weight: 500; color: var(--text-secondary);
  transition: color 0.3s; position: relative;
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 0;
  width: 0; height: 2px; background: var(--primary); transition: width 0.3s;
}
.nav-links a:hover::after { width: 100%; }
.nav-cta {
  background: var(--primary) !important; color: #fff !important;
  padding: 10px 24px; border-radius: 8px; font-weight: 600 !important;
  transition: all 0.3s !important;
}
.nav-cta:hover { background: var(--primary-dark) !important; transform: translateY(-1px); }
.nav-cta::after { display: none !important; }

.mobile-toggle {
  display: none; flex-direction: column; gap: 5px;
  cursor: pointer; background: none; border: none; padding: 4px;
}
.mobile-toggle span {
  width: 24px; height: 2px; background: var(--text-primary);
  border-radius: 2px; transition: all 0.3s;
}

/* ===== THEME TOGGLE (다크/라이트) ===== */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 10px;
  background: transparent;
  border: 1px solid var(--card-border);
  border-radius: 50px;
  cursor: pointer;
  transition: all 0.25s ease;
  font-family: inherit;
  color: var(--text-secondary);
}
.theme-toggle:hover { border-color: rgba(37,99,235,0.4); }
.theme-toggle::after { display: none !important; }
.theme-icon {
  width: 14px; height: 14px; flex-shrink: 0;
  transition: color 0.25s ease, opacity 0.25s ease;
}
.theme-toggle .icon-sun { color: var(--text-muted); opacity: 0.5; }
.theme-toggle .icon-moon { color: var(--text-primary); opacity: 1; }
:root[data-theme="light"] .theme-toggle .icon-sun { color: var(--primary); opacity: 1; }
:root[data-theme="light"] .theme-toggle .icon-moon { color: var(--text-muted); opacity: 0.5; }
.theme-track {
  width: 30px; height: 16px;
  background: var(--card-bg-hover);
  border-radius: 50px;
  position: relative;
  transition: background 0.25s ease;
}
:root[data-theme="light"] .theme-track { background: #d4d4dc; }
.theme-knob {
  position: absolute; top: 2px; left: 2px;
  width: 12px; height: 12px;
  background: var(--primary);
  border-radius: 50%;
  transition: left 0.25s ease, background 0.25s ease;
}
:root[data-theme="light"] .theme-knob { left: 16px; }
@media (max-width: 768px) {
  .theme-toggle { padding: 5px 8px; gap: 6px; }
  .theme-icon { width: 12px; height: 12px; }
  .theme-track { width: 26px; height: 14px; }
  .theme-knob { width: 10px; height: 10px; }
  :root[data-theme="light"] .theme-knob { left: 14px; }
}

/* ===== BUTTON ===== */
.btn {
  padding: 15px 34px; border-radius: 10px; font-size: 0.95rem; font-weight: 600;
  cursor: pointer; border: none; transition: all 0.3s ease;
  display: inline-flex; align-items: center; gap: 8px; font-family: inherit;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 32px var(--accent-glow); }
.btn-outline { background: transparent; color: var(--text-primary); border: 1px solid rgba(255,255,255,0.15); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-2px); }

/* ==========================================================================
 *  POST ARTICLE (개별 글 페이지)
 * ========================================================================== */
.post-article {
  padding: 130px 0 80px;
  background: var(--gradient-hero);
  min-height: 80vh;
}
.post-container { max-width: 780px; margin: 0 auto; padding: 0 24px; }

.post-meta-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 28px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--card-border);
}
.post-back {
  font-size: 0.88rem;
  color: var(--text-muted);
  transition: color 0.3s;
  font-weight: 500;
}
.post-back:hover { color: var(--primary); }
.post-meta-row {
  display: flex; align-items: center; gap: 10px;
  font-size: 0.82rem; color: var(--text-muted);
  font-family: 'Inter', sans-serif;
}
.post-category {
  display: inline-block;
  padding: 4px 12px;
  background: rgba(37,99,235,0.12);
  border: 1px solid rgba(37,99,235,0.3);
  border-radius: 50px;
  color: var(--accent);
  font-weight: 600;
  font-size: 0.75rem;
  letter-spacing: 0.5px;
}
.post-dot { opacity: 0.5; }

.post-title {
  font-size: clamp(1.9rem, 4vw, 2.8rem);
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: 32px;
}
.post-lead {
  font-size: 1.18rem;
  line-height: 1.8;
  color: var(--text-secondary);
  font-weight: 400;
  padding-left: 20px;
  border-left: 3px solid var(--primary);
  margin-bottom: 48px;
}

/* === POST BODY TYPOGRAPHY === */
.post-body {
  font-size: 1.02rem;
  line-height: 1.9;
  color: #d8d8e2;
}
.post-body h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 56px 0 20px;
  letter-spacing: -0.01em;
  line-height: 1.4;
}
.post-body h2::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 1.25rem;
  background: var(--primary);
  border-radius: 2px;
  margin-right: 12px;
  vertical-align: -3px;
}
.post-body h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 36px 0 14px;
}
.post-body p {
  margin-bottom: 20px;
  color: #d8d8e2;
}
.post-body strong { color: var(--text-primary); font-weight: 700; }
.post-body em { color: var(--warm); font-style: normal; font-weight: 600; }

.post-body a {
  color: var(--accent);
  border-bottom: 1px solid rgba(59,130,246,0.3);
  transition: all 0.2s;
}
.post-body a:hover { color: var(--warm); border-bottom-color: var(--warm); }

.post-body code {
  background: rgba(255,255,255,0.06);
  padding: 2px 8px;
  border-radius: 4px;
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-size: 0.9em;
  color: var(--warm);
}

.post-body blockquote {
  margin: 32px 0;
  padding: 24px 28px;
  background: rgba(37,99,235,0.06);
  border-left: 4px solid var(--primary);
  border-radius: 0 12px 12px 0;
  font-size: 1.02rem;
  line-height: 1.8;
  color: var(--text-secondary);
  font-style: normal;
}
.post-body blockquote p { margin-bottom: 0; }
.post-body blockquote p + p { margin-top: 12px; }

.post-body ul, .post-body ol {
  margin: 20px 0 28px 8px;
  padding-left: 20px;
}
.post-body ul li, .post-body ol li {
  margin-bottom: 10px;
  line-height: 1.8;
  position: relative;
  padding-left: 4px;
}
.post-body ul li { list-style: none; }
.post-body ul li::before {
  content: '';
  position: absolute;
  left: -18px;
  top: 0.8em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary);
}
.post-body ol {
  list-style: none;
  counter-reset: postlist;
}
.post-body ol li {
  counter-increment: postlist;
  padding-left: 8px;
}
.post-body ol li::before {
  content: counter(postlist) ".";
  position: absolute;
  left: -24px;
  top: 0;
  color: var(--primary);
  font-weight: 700;
  font-family: 'Inter', sans-serif;
}

.post-figure {
  margin: 40px 0;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  overflow: hidden;
}
.post-figure img {
  width: 100%;
  height: auto;
  display: block;
}
.post-figure figcaption {
  padding: 14px 20px;
  font-size: 0.85rem;
  color: var(--text-muted);
  border-top: 1px solid var(--card-border);
  background: rgba(0,0,0,0.3);
  text-align: center;
}

/* 표 스타일 */
.post-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 32px 0;
  font-size: 0.93rem;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  overflow: hidden;
}
.post-body th, .post-body td {
  padding: 14px 18px;
  text-align: left;
  border-bottom: 1px solid var(--card-border);
}
.post-body th {
  background: rgba(37,99,235,0.1);
  color: var(--text-primary);
  font-weight: 700;
  font-size: 0.88rem;
  letter-spacing: 0.2px;
}
.post-body tr:last-child td { border-bottom: none; }

/* === POST CTA (글 하단 서비스 유도) === */
.post-cta {
  margin-top: 80px;
  padding: 44px 36px;
  background: linear-gradient(135deg, rgba(37,99,235,0.1), rgba(59,130,246,0.05));
  border: 1px solid rgba(37,99,235,0.2);
  border-radius: 20px;
  text-align: center;
}
.post-cta h3 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 12px;
  line-height: 1.4;
}
.post-cta p {
  font-size: 0.98rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
}
.post-cta-buttons {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ==========================================================================
 *  BLOG INDEX (blog.html - 목록 페이지)
 * ========================================================================== */
.blog-hero {
  padding: 140px 0 60px;
  background: var(--gradient-hero);
  position: relative;
  overflow: hidden;
}
.blog-hero::before {
  content: '';
  position: absolute;
  top: -30%;
  right: -15%;
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(37,99,235,0.08) 0%, transparent 55%);
  border-radius: 50%;
  pointer-events: none;
}
.blog-hero .container { position: relative; z-index: 2; }
.blog-hero-label {
  font-family: 'Inter', sans-serif;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 14px;
}
.blog-hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.4rem);
  font-weight: 900;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: 22px;
}
.blog-hero h1 .gradient-text {
  background: linear-gradient(135deg, var(--primary), var(--warm));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.blog-hero-desc {
  font-size: 1.08rem;
  color: var(--text-secondary);
  max-width: 640px;
  line-height: 1.85;
}

/* === CATEGORY FILTER === */
.blog-filter-wrap {
  padding: 40px 0 20px;
  background: var(--dark-bg);
  border-top: 1px solid var(--card-border);
}
.blog-filter {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
}
.filter-label {
  font-family: 'Inter', sans-serif;
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-right: 8px;
}
.filter-btn {
  padding: 8px 18px;
  border-radius: 50px;
  border: 1px solid var(--card-border);
  background: transparent;
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.25s;
  font-family: inherit;
}
.filter-btn:hover {
  border-color: rgba(37,99,235,0.5);
  color: var(--text-primary);
}
.filter-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

/* === POST LIST GRID === */
.blog-list-wrap {
  padding: 40px 0 110px;
  background: var(--dark-bg);
}
.blog-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.blog-card {
  display: flex;
  flex-direction: column;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 18px;
  padding: 28px 26px 30px;
  transition: all 0.35s ease;
  cursor: pointer;
  text-decoration: none;
  min-height: 260px;
}
.blog-card:hover {
  background: var(--card-bg-hover);
  border-color: rgba(37,99,235,0.3);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.35);
}
.blog-card-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.78rem;
  color: var(--text-muted);
  font-family: 'Inter', sans-serif;
  margin-bottom: 18px;
}
.blog-card-category {
  display: inline-block;
  padding: 4px 11px;
  background: rgba(37,99,235,0.12);
  border: 1px solid rgba(37,99,235,0.3);
  border-radius: 50px;
  color: var(--accent);
  font-weight: 600;
  font-size: 0.72rem;
  letter-spacing: 0.4px;
}
.blog-card-title {
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.42;
  letter-spacing: -0.01em;
  margin-bottom: 14px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.blog-card:hover .blog-card-title { color: var(--warm); }
.blog-card-summary {
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 20px;
}
.blog-card-footer {
  margin-top: auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 16px;
  border-top: 1px solid var(--card-border);
  font-size: 0.8rem;
  color: var(--text-muted);
}
.blog-card-arrow {
  color: var(--primary);
  font-weight: 700;
  font-size: 0.9rem;
  transition: transform 0.3s;
}
.blog-card:hover .blog-card-arrow { transform: translateX(4px); }

.blog-empty {
  text-align: center;
  padding: 80px 20px;
  color: var(--text-muted);
  background: var(--card-bg);
  border: 1px dashed var(--card-border);
  border-radius: 20px;
  grid-column: 1 / -1;
}
.blog-empty h3 {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 8px;
}

/* ==========================================================================
 *  FOOTER (index.html과 동일)
 * ========================================================================== */
.footer { padding: 48px 0 28px; background: var(--footer-bg); border-top: 1px solid var(--card-border); }
.footer-top { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 20px; }
.footer-logo { display: flex; flex-direction: column; }
.footer-logo-brand {
  font-family: 'Inter', sans-serif;
  font-size: 1.7rem; font-weight: 900; letter-spacing: -1px; color: var(--text-primary);
}
.footer-logo-blue { color: var(--primary); }
.footer-logo-sub { font-size: 0.72rem; color: var(--text-muted); margin-top: 2px; }
.footer-nav { display: flex; gap: 24px; flex-wrap: wrap; }
.footer-nav a { font-size: 0.82rem; color: var(--text-muted); transition: color 0.3s; }
.footer-nav a:hover { color: var(--text-primary); }
.footer-bottom {
  margin-top: 28px; padding-top: 22px; border-top: 1px solid var(--card-border);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px;
}
.footer-bottom p { font-size: 0.75rem; color: var(--text-muted); }

/* ==========================================================================
 *  RESPONSIVE
 * ========================================================================== */
@media (max-width: 900px) {
  .blog-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; gap: 0;
    background: var(--overlay-bg-heavy);
    backdrop-filter: blur(24px);
    padding: 16px 24px 20px;
    border-bottom: 1px solid var(--card-border);
  }
  .nav-links.active { display: flex; }
  .nav-links a { padding: 12px 0; width: 100%; }
  .mobile-toggle { display: flex; }
  .nav-logo-sub { display: none; }
  .nav-logo-brand { font-size: 1.55rem; }

  .post-article { padding: 100px 0 60px; }
  .post-container { padding: 0 20px; }
  .post-title { font-size: 1.7rem; }
  .post-lead { font-size: 1.05rem; padding-left: 16px; }
  .post-body { font-size: 0.98rem; }
  .post-body h2 { font-size: 1.3rem; margin: 40px 0 16px; }
  .post-body h3 { font-size: 1.05rem; }
  .post-cta { padding: 32px 22px; margin-top: 56px; }
  .post-cta h3 { font-size: 1.18rem; }
  .post-meta-top { flex-direction: column; align-items: flex-start; }

  .blog-hero { padding: 110px 0 44px; }
  .blog-hero h1 { font-size: 1.9rem; }
  .blog-hero-desc { font-size: 1rem; }
  .blog-list-wrap { padding: 30px 0 72px; }
  .blog-grid { grid-template-columns: 1fr; gap: 16px; }
  .blog-card { padding: 24px 22px 26px; }
  .blog-filter { gap: 8px; }
  .filter-btn { padding: 7px 14px; font-size: 0.82rem; }
  .filter-label { width: 100%; margin-bottom: 6px; }

  .footer-top { flex-direction: column; align-items: flex-start; gap: 18px; }
  .footer-nav { gap: 18px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}