:root {
  --bg-main: #090e1a;
  --bg-card: #0f172a;
  --bg-surface: #1e293b;
  --bg-hover: #1e293b;
  --border: #1e293b;
  --border-focus: #38bdf8;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-subtle: #64748b;
  --primary: #38bdf8;
  --primary-hover: #0ea5e9;
  --accent: #818cf8;
  --badge-bg: rgba(56, 189, 248, 0.12);
  --badge-text: #38bdf8;
  --success: #34d399;
  --sidebar-w: 320px;
  --header-h: 60px;
  --font-sans: "Be Vietnam Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

/* Topbar */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: rgba(9, 14, 26, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.topbar-inner {
  max-width: 1400px;
  margin: 0 auto;
  height: 100%;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-area {
  display: flex;
  align-items: center;
  gap: 12px;
}

.portal-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 12px;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.15s ease;
}

.portal-back:hover {
  background: var(--bg-hover);
  color: var(--text-main);
  border-color: var(--text-subtle);
}

.brand-divider {
  width: 1px;
  height: 20px;
  background: var(--border);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}

.brand-badge {
  background: linear-gradient(135deg, #0284c7, #6366f1);
  color: #fff;
  font-weight: 800;
  font-size: 11px;
  padding: 4px 7px;
  border-radius: 6px;
  letter-spacing: 0.5px;
}

.brand-text strong {
  display: block;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.2px;
}

.brand-text small {
  display: block;
  font-size: 11px;
  color: var(--text-muted);
  line-height: 1.1;
}

.topbar-controls {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn-icon {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border-radius: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-muted);
  cursor: pointer;
  font-family: inherit;
  font-size: 13px;
  transition: all 0.15s ease;
}

.btn-icon:hover {
  background: var(--bg-surface);
  color: var(--text-main);
  border-color: var(--primary);
}

.btn-source {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border-radius: 8px;
  background: rgba(56, 189, 248, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.2);
  color: var(--primary);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.15s ease;
}

.btn-source:hover {
  background: rgba(56, 189, 248, 0.16);
  border-color: var(--primary);
}

/* Layout */
.layout-container {
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  min-height: calc(100vh - var(--header-h));
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  border-right: 1px solid var(--border);
  background: #0b1120;
  display: flex;
  flex-direction: column;
  position: sticky;
  top: var(--header-h);
  height: calc(100vh - var(--header-h));
}

.sidebar-header {
  padding: 16px;
  border-bottom: 1px solid var(--border);
}

.search-box {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  color: var(--text-muted);
}

.search-box:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 1px var(--primary);
}

.search-box input {
  background: transparent;
  border: none;
  color: var(--text-main);
  font-family: inherit;
  font-size: 13px;
  width: 100%;
  outline: none;
}

.sidebar-section-title {
  padding: 12px 16px 8px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.pill-count {
  background: var(--bg-surface);
  color: var(--text-muted);
  font-size: 10px;
  padding: 2px 6px;
  border-radius: 10px;
}

.archive-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.archive-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 10px 12px;
  border-radius: 8px;
  text-decoration: none;
  color: var(--text-muted);
  border: 1px solid transparent;
  transition: all 0.15s ease;
  cursor: pointer;
}

.archive-item:hover {
  background: var(--bg-surface);
  color: var(--text-main);
}

.archive-item.active {
  background: rgba(56, 189, 248, 0.1);
  border-color: rgba(56, 189, 248, 0.3);
  color: var(--text-main);
}

.item-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.item-issue {
  font-weight: 700;
  font-size: 13px;
  color: var(--primary);
}

.item-badge-latest {
  background: #059669;
  color: #fff;
  font-size: 9px;
  font-weight: 600;
  padding: 1px 5px;
  border-radius: 4px;
  text-transform: uppercase;
}

.item-badge-git {
  background: rgba(148, 163, 184, 0.15);
  color: var(--text-muted);
  font-size: 9px;
  padding: 1px 5px;
  border-radius: 4px;
}

.item-title {
  font-size: 13px;
  font-weight: 500;
  line-height: 1.4;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.item-date {
  font-size: 11px;
  color: var(--text-subtle);
}

.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  background: #090e1a;
}

.archive-meta {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
  color: var(--text-subtle);
  text-decoration: none;
}

.archive-meta:hover {
  color: var(--primary);
}

/* Reader Main */
.reader-main {
  flex: 1;
  min-width: 0;
  padding: 40px 48px;
  display: flex;
  flex-direction: column;
}

.article-view {
  max-width: 860px;
  margin: 0 auto;
  width: 100%;
  flex: 1;
}

/* Loading state */
.loading-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 400px;
  gap: 16px;
  color: var(--text-muted);
}

.spinner {
  width: 36px;
  height: 36px;
  border: 3px solid rgba(56, 189, 248, 0.15);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Article header */
.article-meta-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.meta-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.badge {
  font-size: 11px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 6px;
}

.badge.primary {
  background: var(--badge-bg);
  color: var(--badge-text);
}

.badge.storage {
  background: rgba(52, 211, 153, 0.1);
  color: var(--success);
  border: 1px solid rgba(52, 211, 153, 0.2);
}

.badge.storage-git {
  background: rgba(148, 163, 184, 0.1);
  color: var(--text-muted);
  border: 1px solid rgba(148, 163, 184, 0.2);
}

.meta-date {
  font-size: 12px;
  color: var(--text-subtle);
}

.mini-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  color: var(--text-muted);
  text-decoration: none;
  padding: 4px 8px;
  border-radius: 6px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  transition: all 0.15s ease;
}

.mini-btn:hover {
  color: var(--text-main);
  border-color: var(--primary);
}

.article-header {
  margin-bottom: 28px;
}

.article-header h1 {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: -0.8px;
  line-height: 1.25;
  color: #fff;
  margin-bottom: 8px;
}

.article-subtitle {
  font-size: 14px;
  color: var(--text-muted);
}

/* TOC */
.toc-container {
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 32px;
}

.toc-title {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--primary);
  margin-bottom: 10px;
}

.toc-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.toc-chip {
  display: inline-block;
  font-size: 12px;
  padding: 5px 12px;
  border-radius: 20px;
  background: var(--bg-surface);
  color: var(--text-muted);
  text-decoration: none;
  border: 1px solid transparent;
  transition: all 0.15s ease;
}

.toc-chip:hover {
  background: rgba(56, 189, 248, 0.15);
  color: var(--primary);
  border-color: rgba(56, 189, 248, 0.3);
}

/* Markdown content typography */
.markdown-body {
  font-size: 16px;
  line-height: 1.8;
  color: #e2e8f0;
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3 {
  color: #fff;
  font-weight: 700;
  scroll-margin-top: 80px;
}

.markdown-body h2 {
  font-size: 1.55rem;
  margin-top: 48px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
  letter-spacing: -0.4px;
}

.markdown-body h3 {
  font-size: 1.25rem;
  margin-top: 28px;
  margin-bottom: 12px;
}

.markdown-body p {
  margin-bottom: 18px;
}

.markdown-body a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s ease;
}

.markdown-body a:hover {
  color: #7dd3fc;
}

.markdown-body img {
  max-width: 100%;
  border-radius: 10px;
  margin: 16px 0;
  border: 1px solid var(--border);
  display: block;
}

.markdown-body blockquote {
  border-left: 3px solid var(--primary);
  background: rgba(56, 189, 248, 0.05);
  padding: 12px 18px;
  border-radius: 0 8px 8px 0;
  margin: 20px 0;
  color: var(--text-muted);
}

.markdown-body ul,
.markdown-body ol {
  padding-left: 24px;
  margin-bottom: 20px;
}

.markdown-body li {
  margin-bottom: 8px;
}

.markdown-body pre {
  background: #070b14;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  overflow-x: auto;
  margin: 20px 0;
  font-family: var(--font-mono);
  font-size: 13.5px;
}

.markdown-body code {
  font-family: var(--font-mono);
  font-size: 13.5px;
  background: rgba(255, 255, 255, 0.07);
  padding: 2px 6px;
  border-radius: 4px;
}

.markdown-body pre code {
  background: transparent;
  padding: 0;
}

.markdown-body hr {
  border: none;
  height: 1px;
  background: var(--border);
  margin: 36px 0;
}

/* Footer nav */
.article-footer-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.nav-btn {
  display: flex;
  flex-direction: column;
  padding: 12px 18px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  color: var(--text-main);
  cursor: pointer;
  font-family: inherit;
  text-align: left;
  min-width: 180px;
  transition: all 0.15s ease;
}

.nav-btn:hover:not(:disabled) {
  background: var(--bg-surface);
  border-color: var(--primary);
}

.nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.nav-btn.next {
  text-align: right;
  margin-left: auto;
}

.nav-direction {
  font-size: 11px;
  color: var(--primary);
  font-weight: 600;
  text-transform: uppercase;
}

.nav-issue-title {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 260px;
}

/* Footer */
.footer {
  margin-top: 60px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 12px;
  color: var(--text-subtle);
}

.footer a {
  color: var(--text-muted);
  text-decoration: none;
}

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

/* Responsive */
@media (max-width: 900px) {
  .sidebar {
    position: fixed;
    left: -340px;
    top: 0;
    bottom: 0;
    height: 100vh;
    z-index: 100;
    width: 320px;
    transition: left 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: 10px 0 25px rgba(0,0,0,0.5);
  }

  .sidebar.open {
    left: 0;
  }

  .sidebar-backdrop {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 99;
  }

  .sidebar-backdrop.active {
    display: block;
  }

  .reader-main {
    padding: 24px 20px;
  }

  .article-header h1 {
    font-size: 1.7rem;
  }
}