:root {
  --bg: #f7f9fb;
  --paper: #ffffff;
  --text: #191c1e;
  --text-2: #424754;
  --muted: #727785;
  --line: rgba(194, 198, 214, 0.3);
  --line-strong: #c2c6d6;
  --primary: #0058be;
  --primary-2: #2170e4;
  --mint: #bde7eb;
  --mint-text: #41696d;
  --footer-bg: #eceef0;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.06);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: inherit; }

/* ───────── Top Navigation ───────── */
.top-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: 64px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(194, 198, 214, 0.4);
}

.top-nav-inner {
  max-width: 1140px;
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.top-nav-left {
  display: flex;
  align-items: center;
  gap: 32px;
}

.brand {
  font-size: 20px;
  font-weight: 800;
  color: var(--primary);
  letter-spacing: -0.5px;
  text-decoration: none;
}

.top-nav-menu {
  display: flex;
  gap: 28px;
}

.top-nav-menu a {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-2);
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: color 150ms ease;
}

.top-nav-menu a:hover { color: var(--primary); }

.top-nav-right { display: flex; align-items: center; gap: 12px; }

.subscribe-btn {
  display: inline-flex;
  align-items: center;
  padding: 8px 24px;
  background: var(--primary);
  color: #fff;
  font-size: 16px;
  border-radius: 9999px;
  text-decoration: none;
  box-shadow: var(--shadow-md);
  transition: background 150ms ease, transform 150ms ease;
}

.subscribe-btn:hover { background: #004a9e; transform: translateY(-1px); }

/* ───────── Hero Banner ───────── */
.hero-banner {
  position: relative;
  height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #fff;
  border-bottom: 1px solid rgba(194, 198, 214, 0.05);
  overflow: hidden;
}

.hero-banner-gradient {
  position: absolute;
  inset: 0;
  opacity: 0.5;
  background:
    radial-gradient(circle at 28% 0%, rgba(0, 88, 190, 0.08), transparent 35%),
    radial-gradient(circle at 78% 100%, rgba(33, 112, 228, 0.06), transparent 40%),
    linear-gradient(135deg, rgba(247, 249, 251, 1) 0%, rgba(238, 242, 255, 0.6) 50%, rgba(247, 249, 251, 1) 100%);
  pointer-events: none;
}

.hero-banner-content {
  position: relative;
  z-index: 2;
  max-width: 896px;
  padding: 0 24px;
  text-align: center;
  pointer-events: none;
}

.hero-banner-title {
  margin: 0 0 12px;
  font-size: 48px;
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.96px;
  color: var(--text);
}

.hero-banner-subtitle {
  margin: 0 auto;
  max-width: 576px;
  font-size: 16px;
  line-height: 1.5;
  color: rgba(66, 71, 84, 0.8);
}

/* ───────── Bubble Field ───────── */
.bubble-field {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 1;
}

.bubble {
  position: absolute;
  bottom: -80px;
  border: 1px solid rgba(255, 255, 255, 0.45);
  border-radius: 9999px;
  padding: 0;
  background:
    radial-gradient(circle at 32% 28%, rgba(255, 255, 255, 0.85) 0%, rgba(255, 255, 255, 0.25) 30%, rgba(33, 112, 228, 0.1) 65%, rgba(0, 88, 190, 0.18) 100%);
  box-shadow:
    inset -1px -2px 4px rgba(0, 88, 190, 0.08),
    inset 1px 1px 3px rgba(255, 255, 255, 0.35);
  cursor: pointer;
  pointer-events: auto;
  opacity: 0;
  transform: translate3d(0, 0, 0) scale(0.6);
  animation-name: bubbleRise;
  animation-timing-function: cubic-bezier(0.22, 0.61, 0.36, 1);
  animation-fill-mode: forwards;
  transition: transform 120ms ease;
  will-change: transform, opacity;
}

.bubble::before {
  content: "";
  position: absolute;
  top: 14%;
  left: 22%;
  width: 28%;
  height: 22%;
  border-radius: 9999px;
  background: rgba(255, 255, 255, 0.85);
  filter: blur(1px);
  pointer-events: none;
}

.bubble:hover { transform: translate3d(0, 0, 0) scale(1.08); }

.bubble[data-popped] { pointer-events: none; }

@keyframes bubbleRise {
  0% {
    transform: translate3d(0, 0, 0) scale(0.55);
    opacity: 0;
  }
  12% {
    opacity: 0.95;
    transform: translate3d(calc(var(--drift, 0px) * 0.15), -40px, 0) scale(1);
  }
  85% {
    opacity: 0.85;
  }
  100% {
    transform: translate3d(var(--drift, 0px), -360px, 0) scale(1);
    opacity: 0;
  }
}

.bubble-shard {
  position: absolute;
  border-radius: 9999px;
  background: radial-gradient(circle at 35% 30%, rgba(255, 255, 255, 0.95), rgba(33, 112, 228, 0.4) 70%, rgba(0, 88, 190, 0.25));
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 3;
  animation: shardFly 560ms cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
}

@keyframes shardFly {
  0% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
  60% {
    opacity: 0.7;
  }
  100% {
    transform: translate(calc(-50% + var(--dx)), calc(-50% + var(--dy) + 14px)) scale(0.35);
    opacity: 0;
  }
}

.bubble-ring {
  position: absolute;
  border-radius: 9999px;
  border: 3px solid rgba(0, 88, 190, 0.85);
  box-shadow:
    0 0 12px rgba(33, 112, 228, 0.35),
    inset 0 0 6px rgba(33, 112, 228, 0.25);
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 3;
  opacity: 0;
  animation: ringExpand 780ms cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes ringExpand {
  0% {
    transform: translate(-50%, -50%) scale(0.35);
    opacity: 0;
    border-width: 3px;
  }
  18% {
    opacity: 1;
  }
  60% {
    opacity: 0.55;
  }
  100% {
    transform: translate(-50%, -50%) scale(3.4);
    opacity: 0;
    border-width: 0.5px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .bubble-field { display: none; }
}

/* ───────── Page Layout ───────── */
.page-wrap {
  max-width: 1140px;
  margin: 0 auto;
  padding: 48px 24px 64px;
}

.page-grid {
  display: grid;
  grid-template-columns: 256px minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

.page-content { min-width: 0; }

/* ───────── Sidebar ───────── */
.sidebar {
  position: sticky;
  top: 88px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.sidebar-section { padding: 8px 16px; }

.sidebar-title {
  margin: 0 0 6px;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.3;
}

.sidebar-title-sm {
  margin: 24px 0 12px;
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.sidebar-subtitle {
  margin: 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-2);
  letter-spacing: 0.28px;
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-top: 4px;
}

.sidebar-nav-link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text-2);
  text-decoration: none;
  transition: background 150ms ease, color 150ms ease;
}

.sidebar-nav-link:hover { background: rgba(189, 231, 235, 0.4); }

.sidebar-nav-link.is-active {
  background: var(--mint);
  color: var(--mint-text);
}

.sidebar-nav-icon {
  display: inline-grid;
  place-items: center;
  width: 20px;
  height: 20px;
  font-size: 14px;
  color: currentColor;
  opacity: 0.85;
}

/* ───────── Newsletter Card ───────── */
.newsletter-card {
  margin-top: 32px;
  padding: 24px;
  background: var(--primary-2);
  border-radius: 12px;
  color: #fff;
}

.newsletter-title {
  margin: 0 0 8px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.28px;
}

.newsletter-copy {
  margin: 0 0 16px;
  font-size: 14px;
  line-height: 1.45;
  opacity: 0.9;
}

.newsletter-form {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.newsletter-input {
  height: 44px;
  padding: 0 12px;
  border: none;
  border-radius: 8px;
  background: #fff;
  font: inherit;
  font-size: 15px;
  color: var(--text);
}

.newsletter-input::placeholder { color: #6b7280; }

.newsletter-button {
  height: 40px;
  border: none;
  border-radius: 8px;
  background: #fefcff;
  color: var(--primary-2);
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: background 150ms ease;
}

.newsletter-button:hover { background: #e9eefb; }

/* ───────── Recent List in Sidebar ───────── */
.recent-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
}

.recent-list li {
  padding: 10px 16px;
  border-bottom: 1px dashed var(--line);
}

.recent-list li:last-child { border-bottom: none; }

.recent-list a {
  display: block;
  font-size: 13px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text);
  text-decoration: none;
  margin-bottom: 4px;
}

.recent-list a:hover { color: var(--primary); }

.recent-date {
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.04em;
}

/* ───────── Article List (Home) ───────── */
.article-list {
  border-top: 1px solid var(--line);
  display: flex;
  flex-direction: column;
}

.article-item {
  padding: 32px 16px 33px;
  margin: 0 -16px;
  border-bottom: 1px solid var(--line);
  border-radius: 8px;
  transition: background 150ms ease;
}

.article-item:hover { background: rgba(247, 249, 251, 0.6); }

.article-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.article-category {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 1.4px;
}

.article-dot {
  font-size: 14px;
  color: var(--muted);
  line-height: 1;
}

.article-date,
.article-readtime {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-2);
  letter-spacing: 0.02em;
}

.article-title {
  margin: 0 0 16px;
  font-size: 32px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.32px;
}

.article-title a {
  color: var(--text);
  text-decoration: none;
  transition: color 150ms ease;
}

.article-title a:hover { color: var(--primary); }

.article-excerpt {
  margin: 0 0 24px;
  max-width: 768px;
  font-size: 18px;
  line-height: 1.75;
  color: var(--text-2);
}

.article-author {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-top: 8px;
}

.article-author-avatar {
  display: inline-grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border-radius: 9999px;
  background: var(--mint);
  color: var(--mint-text);
  font-size: 11px;
  font-weight: 700;
}

.article-author-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-2);
  letter-spacing: 0.02em;
}

.empty-state {
  padding: 48px 0;
  text-align: center;
  color: var(--muted);
}

/* ───────── Post Detail ───────── */
.post {
  max-width: 768px;
  padding: 8px 0 24px;
}

.post-header {
  padding-bottom: 28px;
  margin-bottom: 32px;
  border-bottom: 1px solid var(--line);
}

.post-category {
  margin: 0 0 14px;
}

.post-category a {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 9999px;
  background: var(--mint);
  color: var(--mint-text);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  text-decoration: none;
}

.post-header h1 {
  margin: 0 0 16px;
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.5px;
  color: var(--text);
}

.post-date {
  margin: 0 0 12px;
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.post-description {
  margin: 0;
  font-size: 18px;
  line-height: 1.6;
  color: var(--text-2);
}

.post-body {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text);
}

.post-body p,
.post-body ul,
.post-body ol,
.post-body blockquote { margin: 0 0 1.2rem; }

.post-body h2,
.post-body h3 {
  margin: 2.4rem 0 0.9rem;
  font-weight: 700;
  line-height: 1.3;
  color: var(--text);
}

.post-body h2 { font-size: 1.6rem; }
.post-body h3 { font-size: 1.25rem; }

.post-body a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.post-body code {
  padding: 2px 6px;
  border-radius: 6px;
  background: rgba(0, 88, 190, 0.08);
  font-size: 0.92em;
  font-family: "JetBrains Mono", "SF Mono", Consolas, monospace;
}

.post-body pre {
  padding: 18px 20px;
  border-radius: 12px;
  background: #0f172a;
  color: #e2e8f0;
  overflow-x: auto;
  font-size: 14px;
  line-height: 1.6;
}

.post-body pre code {
  padding: 0;
  background: transparent;
  color: inherit;
}

.post-body blockquote {
  padding: 14px 20px;
  border-left: 3px solid var(--primary);
  background: rgba(0, 88, 190, 0.05);
  border-radius: 0 12px 12px 0;
  color: var(--text-2);
}

.tag-list {
  list-style: none;
  padding: 0;
  margin: 32px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag-list li a {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 9999px;
  background: rgba(0, 88, 190, 0.08);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  transition: background 150ms ease;
}

.tag-list li a:hover { background: rgba(0, 88, 190, 0.16); }

.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-top: 48px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.post-nav-link {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 20px;
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  background: #fff;
  text-decoration: none;
  color: inherit;
  transition: transform 150ms ease, border-color 150ms ease, box-shadow 150ms ease;
}

.post-nav-link:hover {
  transform: translateY(-2px);
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.post-nav-empty {
  background: transparent;
  border: 1px dashed var(--line-strong);
}

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

.post-nav-label {
  font-size: 12px;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.post-nav-title {
  font-size: 15px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text);
}

/* ───────── Archive Pages ───────── */
.archive-page {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.archive-eyebrow {
  margin: 0 0 10px;
  font-size: 13px;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.14em;
}

.tag-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 24px 0 8px;
}

.tag-chip {
  padding: 8px 16px;
  border: 1px solid var(--line-strong);
  border-radius: 9999px;
  background: #fff;
  font: inherit;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-2);
  cursor: pointer;
  transition: background 150ms ease, color 150ms ease, border-color 150ms ease, transform 100ms ease;
}

.tag-chip:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.tag-chip.is-active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.tag-chip.is-active:hover { color: #fff; }

.article-tag-pill {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 9999px;
  background: rgba(0, 88, 190, 0.08);
  color: var(--primary);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.archive-header h1 {
  margin: 0 0 8px;
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -0.5px;
  color: var(--text);
}

.archive-copy {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
}

.archive-group { scroll-margin-top: 96px; }

.archive-group-title {
  margin: 0 0 14px;
  padding-bottom: 10px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  gap: 10px;
}

.archive-group-title span {
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  background: rgba(194, 198, 214, 0.25);
  padding: 2px 10px;
  border-radius: 9999px;
}

.archive-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
}

.archive-list li a {
  display: flex;
  gap: 16px;
  padding: 12px 14px;
  border-radius: 10px;
  text-decoration: none;
  color: inherit;
  transition: background 150ms ease;
}

.archive-list li a:hover { background: rgba(0, 88, 190, 0.05); }

.archive-date {
  flex-shrink: 0;
  min-width: 110px;
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
}

.archive-title {
  font-size: 15px;
  color: var(--text);
}

/* ───────── Footer ───────── */
.site-footer {
  margin-top: 64px;
  padding: 65px 24px 64px;
  background: var(--footer-bg);
  border-top: 1px solid var(--line);
}

.site-footer-inner {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.site-footer-brand { display: flex; flex-direction: column; gap: 6px; }

.site-footer-name {
  margin: 0;
  font-size: 24px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.3;
}

.site-footer-copy {
  margin: 0;
  font-size: 16px;
  color: var(--text-2);
}

.site-footer-nav {
  display: flex;
  gap: 32px;
  flex-wrap: wrap;
}

.site-footer-nav a {
  font-size: 16px;
  color: var(--text-2);
  text-decoration: none;
  transition: color 150ms ease;
}

.site-footer-nav a:hover { color: var(--primary); }

/* ───────── Responsive ───────── */
@media (max-width: 960px) {
  .page-grid {
    grid-template-columns: 1fr;
  }
  .sidebar {
    position: static;
    order: 2;
  }
  .page-content { order: 1; }
}

@media (max-width: 720px) {
  .top-nav-menu { display: none; }
  .top-nav-inner { padding: 0 16px; }
  .page-wrap { padding: 32px 16px 48px; }
  .hero-banner { height: 240px; }
  .hero-banner-title { font-size: 36px; }
  .hero-banner-subtitle { font-size: 15px; }
  .article-title { font-size: 24px; }
  .article-excerpt { font-size: 16px; line-height: 1.65; }
  .article-item { padding: 24px 16px; }
  .site-footer { padding: 48px 16px; }
  .site-footer-inner { padding: 0; flex-direction: column; align-items: flex-start; }
  .site-footer-nav { gap: 20px; }
  .post-nav { grid-template-columns: 1fr; }
  .post-nav-next { text-align: left; }
}