/* =============================================
   Yunhwan's Dev Blog - Woowahan-inspired theme
   ============================================= */

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

:root {
  --primary: #2AC1BC;
  --primary-dark: #219A96;
  --primary-light: #E8F8F7;
  --text: #292929;
  --text-secondary: #6B6B6B;
  --text-light: #999;
  --bg: #FFFFFF;
  --bg-gray: #F8F9FA;
  --border: #EAEAEA;
  --card-shadow: 0 1px 4px rgba(0, 0, 0, 0.04), 0 4px 12px rgba(0, 0, 0, 0.03);
  --card-shadow-hover: 0 4px 12px rgba(0, 0, 0, 0.08), 0 8px 24px rgba(0, 0, 0, 0.06);
  --max-width: 780px;
  --header-height: 64px;
  --radius: 12px;
}

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

body {
  font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--text);
  background: var(--bg-gray);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  height: auto;
}

/* =============================================
   Header
   ============================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: var(--header-height);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-text {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  padding: 6px 14px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: 8px;
  transition: all 0.2s ease;
}

.nav-link:hover {
  color: var(--primary);
  background: var(--primary-light);
}

.nav-link.active {
  color: var(--primary);
  font-weight: 700;
}

/* =============================================
   Content Area
   ============================================= */
.site-content {
  min-height: calc(100vh - var(--header-height) - 80px);
}

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

.content-inner--wide {
  max-width: 1080px;
}

/* =============================================
   Hero
   ============================================= */
.hero {
  position: relative;
  padding: 72px 24px 56px;
  text-align: center;
  background: linear-gradient(135deg, #E8F8F7 0%, #F0F4FF 50%, #FFF5F0 100%);
  border-bottom: 1px solid var(--border);
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 50%, rgba(42, 193, 188, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 30%, rgba(137, 180, 250, 0.08) 0%, transparent 50%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  max-width: var(--max-width);
  margin: 0 auto;
}

.hero-greeting {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 8px;
}

.hero-title {
  font-size: 2rem;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.04em;
  line-height: 1.3;
}

.hero-divider {
  width: 40px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), #89B4FA);
  margin: 20px auto;
  border-radius: 2px;
}

.hero-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 400;
  letter-spacing: -0.01em;
}

/* =============================================
   Category & Tag Filter
   ============================================= */
.category-filter {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 28px 24px;
  max-width: var(--max-width);
  margin: 0 auto;
}

.filter-group {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.filter-label {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-light);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  min-width: 64px;
  flex-shrink: 0;
}

.category-tab {
  padding: 5px 14px;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 20px;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: inherit;
}

.category-tab:hover {
  color: var(--primary);
  border-color: var(--primary);
}

.category-tab.active {
  color: #fff;
  background: var(--primary);
  border-color: var(--primary);
}

/* =============================================
   Post Card List
   ============================================= */
.post-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding-top: 24px;
  padding-bottom: 80px;
}

.post-card {
  background: var(--bg);
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  overflow: hidden;
  transition: all 0.25s ease;
}

.post-card:hover {
  box-shadow: var(--card-shadow-hover);
  transform: translateY(-2px);
}

.post-card-link {
  display: flex;
  flex-direction: row;
}

.post-card-thumbnail {
  flex-shrink: 0;
  width: 240px;
  min-height: 160px;
  overflow: hidden;
}

.post-card-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.post-card:hover .post-card-thumbnail img {
  transform: scale(1.05);
}

.post-card-body {
  flex: 1;
  padding: 28px 32px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.post-card-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  font-size: 0.82rem;
  color: var(--text-light);
}

.post-card-category {
  display: inline-block;
  padding: 2px 10px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--primary);
  background: var(--primary-light);
  border-radius: 20px;
  letter-spacing: 0.02em;
}

.post-card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.5;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.post-card-excerpt {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 12px;
}

/* =============================================
   Post Layout (2-column)
   ============================================= */
.post-layout {
  display: grid;
  grid-template-columns: 1fr 220px;
  gap: 48px;
  align-items: start;
}

.post-sidebar {
  padding-top: 60px;
}

.sidebar-sticky {
  position: sticky;
  top: calc(var(--header-height) + 24px);
}

.sidebar-section {
  background: var(--bg);
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  padding: 20px;
}

.sidebar-title {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-light);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.sidebar-category-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar-category-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: all 0.2s ease;
}

.sidebar-category-link:hover {
  color: var(--primary);
  background: var(--primary-light);
}

.sidebar-category-link.active {
  color: var(--primary);
  background: var(--primary-light);
  font-weight: 600;
}

.sidebar-category-name {
  font-weight: 500;
}

.sidebar-category-count {
  font-size: 0.75rem;
  color: var(--text-light);
  background: var(--bg-gray);
  padding: 1px 8px;
  border-radius: 10px;
  font-weight: 500;
}

.sidebar-category-link.active .sidebar-category-count {
  background: rgba(42, 193, 188, 0.15);
  color: var(--primary-dark);
}

/* =============================================
   Post Detail
   ============================================= */
.post {
  padding-bottom: 80px;
  min-width: 0;
}

.post-header {
  padding: 60px 0 32px;
  text-align: center;
}

.post-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-bottom: 16px;
  font-size: 0.85rem;
  color: var(--text-light);
}

.post-title {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.4;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.post-thumbnail {
  margin-bottom: 40px;
  border-radius: var(--radius);
  overflow: hidden;
}

.post-thumbnail img {
  width: 100%;
  display: block;
}

/* Post Content */
.post-content {
  font-size: 1rem;
  line-height: 1.9;
  color: var(--text);
}

.post-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 48px 0 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-light);
  letter-spacing: -0.02em;
}

.post-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 36px 0 12px;
  letter-spacing: -0.01em;
}

.post-content h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 28px 0 8px;
}

.post-content p {
  margin-bottom: 20px;
}

.post-content ul,
.post-content ol {
  margin: 0 0 20px 24px;
}

.post-content li {
  margin-bottom: 6px;
}

.post-content a {
  color: var(--primary);
  font-weight: 500;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}

.post-content a:hover {
  border-bottom-color: var(--primary);
}

.post-content blockquote {
  margin: 24px 0;
  padding: 16px 24px;
  border-left: 4px solid var(--primary);
  background: var(--primary-light);
  border-radius: 0 8px 8px 0;
  color: var(--text-secondary);
  font-style: normal;
}

.post-content blockquote p:last-child {
  margin-bottom: 0;
}

.post-content img {
  border-radius: 8px;
  margin: 24px 0;
}

.post-content hr {
  border: none;
  height: 1px;
  background: var(--border);
  margin: 40px 0;
}

.post-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 0.92rem;
}

.post-content th,
.post-content td {
  padding: 12px 16px;
  border: 1px solid var(--border);
  text-align: left;
}

.post-content th {
  background: var(--bg-gray);
  font-weight: 600;
}

/* Code Blocks */
.post-content code {
  font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  font-size: 0.88em;
  background: var(--bg-gray);
  padding: 2px 6px;
  border-radius: 4px;
  color: #E96900;
}

.post-content pre {
  margin: 24px 0;
  padding: 20px 24px;
  background: #1E1E2E;
  color: #CDD6F4;
  border-radius: var(--radius);
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.7;
}

.post-content pre code {
  background: none;
  padding: 0;
  border-radius: 0;
  color: inherit;
  font-size: inherit;
}

/* Post Footer */
.post-footer {
  margin-top: 60px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.post-author {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 24px;
  background: var(--bg-gray);
  border-radius: var(--radius);
  margin-bottom: 32px;
}

.post-author strong {
  font-size: 1rem;
  color: var(--text);
}

.post-author span {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.post-nav-prev,
.post-nav-next {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 20px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all 0.2s ease;
}

.post-nav-next {
  text-align: right;
}

.post-nav-prev:hover,
.post-nav-next:hover {
  border-color: var(--primary);
  box-shadow: var(--card-shadow);
}

.post-nav-label {
  font-size: 0.78rem;
  color: var(--text-light);
  font-weight: 500;
}

.post-nav-title {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.5;
}

/* =============================================
   Page
   ============================================= */
.page {
  padding-bottom: 80px;
}

.page-header {
  padding: 60px 0 32px;
}

.page-title {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
}

/* =============================================
   Footer
   ============================================= */
.site-footer {
  padding: 32px 0;
  text-align: center;
  border-top: 1px solid var(--border);
  background: var(--bg);
}

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

.site-footer p {
  font-size: 0.82rem;
  color: var(--text-light);
}

/* =============================================
   Rouge Syntax Highlighting (Dark)
   ============================================= */
.highlight .k, .highlight .kd, .highlight .kn,
.highlight .kp, .highlight .kr, .highlight .kt { color: #CBA6F7; }
.highlight .s, .highlight .s1, .highlight .s2,
.highlight .sh, .highlight .sx { color: #A6E3A1; }
.highlight .c, .highlight .cm, .highlight .c1,
.highlight .cs { color: #6C7086; font-style: italic; }
.highlight .nf, .highlight .nb { color: #89B4FA; }
.highlight .nc, .highlight .nn { color: #F9E2AF; }
.highlight .mi, .highlight .mf, .highlight .mh { color: #FAB387; }
.highlight .o, .highlight .ow { color: #89DCEB; }
.highlight .p { color: #CDD6F4; }
.highlight .na { color: #89B4FA; }

/* =============================================
   Responsive
   ============================================= */
@media (max-width: 768px) {
  :root {
    --header-height: 56px;
  }

  .hero {
    padding: 40px 20px 32px;
  }

  .hero-title {
    font-size: 1.4rem;
  }

  .post-layout {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .post-sidebar {
    padding-top: 0;
    order: -1;
  }

  .sidebar-sticky {
    position: static;
  }

  .post-card-link {
    flex-direction: column;
  }

  .post-card-thumbnail {
    width: 100%;
    min-height: 180px;
    max-height: 200px;
  }

  .post-card-body {
    padding: 20px;
  }

  .post-card-title {
    font-size: 1.1rem;
  }

  .post-title {
    font-size: 1.6rem;
  }

  .post-content h2 {
    font-size: 1.3rem;
  }

  .post-nav {
    grid-template-columns: 1fr;
  }

  .nav-link {
    padding: 6px 10px;
    font-size: 0.85rem;
  }

  .category-filter {
    padding: 20px 16px;
    gap: 12px;
  }

  .filter-group {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .filter-label {
    min-width: auto;
  }
}

@media (max-width: 480px) {
  .content-inner {
    padding: 0 16px;
  }

  .header-inner {
    padding: 0 16px;
  }

  .hero-title {
    font-size: 1.25rem;
  }

  .post-title {
    font-size: 1.4rem;
  }
}