/* ============================================
   Simple Theme — AstroPaper-inspired
   Clean, minimal, typography-first blog theme
   ============================================ */

:root {
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: Palatino, 'Courier New', monospace;
  --max-w: 48rem;
  --gap: 1.5rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: linear-gradient(30deg, var(--bg-tint), var(--bg));
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: color 0.2s;
  min-height: 100vh;
}

::selection {
  background: var(--selection);
}

/* --- Focus --- */
*:focus-visible {
  outline: 2px dashed var(--accent);
  outline-offset: 4px;
}

/* --- Skip Link --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  z-index: 100;
  border-radius: 0 0 4px 4px;
  text-decoration: none;
}
.skip-link:focus {
  top: 0;
}

/* --- Layout Container --- */
.layout-container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* --- Header --- */
.site-header {
  padding: 1rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 2rem;
  transition: box-shadow 0.3s ease-in-out;
  cursor: pointer;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.site-header:hover {
  border-radius: 1rem;
  box-shadow: 0 0 12px var(--line);
}

.site-logo {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  text-decoration: none;
  color: var(--text);
  transition: color 0.2s;
  white-space: nowrap;
}
.site-logo:hover {
  color: var(--accent);
}

.header-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

.nav-link {
  font-size: 0.9375rem;
  font-weight: 500;
  text-decoration: none;
  color: var(--text-muted);
  transition: color 0.2s;
  padding: 0.25rem 0;
}
.nav-link:hover,
.nav-link.nav-current {
  color: var(--accent);
}

/* --- Header Actions (right-side button group) --- */
.header-actions {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-shrink: 0;
}

/* --- Scheme Button Wrapper (positioning anchor for popup) --- */
.scheme-btn-wrapper {
  position: relative;
  display: flex;
}



/* --- Theme Toggle --- */
.theme-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-muted);
  padding: 0.25rem;
  display: flex;
  align-items: center;
  transition: color 0.2s;
  flex-shrink: 0;
}
.theme-btn:hover {
  color: var(--accent);
}
.theme-btn svg {
  width: 1.25rem;
  height: 1.25rem;
}
html.dark .icon-sun { display: block; }
html.dark .icon-moon { display: none; }
.icon-sun { display: none; }
.icon-moon { display: block; }

/* --- Scheme Toggle --- */
.scheme-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-muted);
  padding: 0.25rem;
  display: flex;
  align-items: center;
  transition: color 0.2s;
  flex-shrink: 0;
}
.scheme-btn:hover {
  color: var(--accent);
}
.scheme-btn svg {
  width: 1.125rem;
  height: 1.125rem;
}

/* --- Scheme Popup (desktop dropdown) --- */
.scheme-popup {
  display: none;
  position: absolute;
  top: 100%;
  right: 0;
  margin-top: 0.5rem;
  min-width: 180px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.12);
  padding: 0.75rem;
  z-index: 200;
}
.scheme-popup.active {
  display: block;
}
.scheme-popup-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.625rem;
}

/* --- Scheme Picker (mobile drawer inline) --- */
.scheme-picker {
  display: none;
  margin-top: 0.5rem;
  padding: 0.75rem;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 8px;
}
.scheme-picker.active {
  display: block;
}

/* --- Popup/Picker grid --- */
.scheme-popup-grid,
.scheme-picker-grid {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

/* --- Individual Scheme Swatch --- */
.scheme-swatch {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  padding: 0.5rem 0.625rem;
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.15s;
}
.scheme-swatch:hover {
  background: var(--line);
}
.scheme-swatch.active {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.scheme-swatch-bar {
  display: flex;
  height: 1.5rem;
  width: 3rem;
  border-radius: 4px;
  overflow: hidden;
  flex-shrink: 0;
  border: 1px solid var(--line);
}
.scheme-swatch-bar span {
  flex: 1;
}

.scheme-swatch-label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text);
}



/* --- Menu Button (mobile) --- */
.menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text);
  padding: 0.25rem;
  flex-shrink: 0;
}

/* --- Main Content --- */
.main-content {
  padding: 1rem;
  flex: 1;
  padding-bottom: 3rem;
}

/* --- Section --- */
.section {
  margin-bottom: 3rem;
}

.section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 1.5rem;
  gap: 1rem;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.3;
}

.section-more {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.2s;
  font-family: var(--font-mono);
}
.section-more:hover {
  color: var(--accent-hover);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* --- Hero --- */
.hero {
  padding: 1.5rem 0 2.5rem;
}

.hero-title {
  font-size: 3rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 0.75rem;
}

.hero-avatar {
  display: inline-block;
  margin-right: 0.5rem;
}

.hero-avatar img {
  width: 40px;
  border-radius: 50%;
  vertical-align: middle;
}

.hero-desc {
  font-size: 1.3rem;
  color: var(--text-muted);
  max-width: 36rem;
  line-height: 1.6;
}

.hero-intro {
  margin-top: 1rem;
  font-size: 0.9375rem;
  line-height: 1.7;
  background-color: var(--selection);
}

.hero-banner img {
  width: 100%;
  border-radius: 10px;
  margin-top: 0.3rem;
}

/* --- Post List --- */
.post-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.post-item {
  border-bottom: 1px solid var(--line);
  padding-bottom: 1.5rem;
  transition: transform 0.3s ease-in-out;
}

.post-item:hover {
  transform: translateX(2px) translateY(2px);
}

.index-app .post-item {
  border-bottom: none;
  padding-bottom: 0;
}

.post-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.post-title {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 0.375rem;
}

.post-link {
  color: var(--text);
  text-decoration: none;
  transition: color 0.2s;
}
.post-link:hover {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 2px;
}

.post-meta {
  font-size: 0.8125rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem;
}

.meta-sep {
  color: var(--line);
}

.post-cat {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}
.post-cat:hover {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.post-desc {
  font-size: 0.9375rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 0.5rem;
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.375rem;
}

.tag-link {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}
.tag-link:hover {
  color: var(--accent);
}

/* --- Filter Bar --- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 2rem;
}

.filter-btn {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  padding: 0.375rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text-muted);
  text-decoration: none;
  transition: all 0.2s;
  flex-shrink: 0;
}
.filter-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}
.filter-btn.filter-active {
  border-color: var(--accent);
  background: var(--accent);
  color: #fff;
}

/* --- Pagination --- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
}

.page-btn {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  padding: 0.5rem 1rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--text);
  text-decoration: none;
  transition: all 0.2s;
}
.page-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.page-info {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-muted);
}

/* --- Post Full (Detail) --- */
.post-full {
  padding-bottom: 2rem;
}

.post-full-header {
  margin-bottom: 2.5rem;
}

.post-full-title {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.25;
  margin-bottom: 0.75rem;
}

.post-hero {
  margin: 1.5rem 0;
  border-radius: 8px;
  overflow: hidden;
}
.post-hero img {
  width: 100%;
  height: auto;
  display: block;
}

.post-sep {
  border: none;
  border-top: 1px dashed var(--line);
  margin: 2.5rem 0;
}

.post-nav-back {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s;
}
.post-nav-back:hover {
  color: var(--accent-hover);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* --- Post Content (Markdown Body) --- */
.post-content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text);
}

.post-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.post-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

.post-content p {
  margin-bottom: 1.25rem;
}

.post-content a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: color 0.2s;
}
.post-content a:hover {
  color: var(--accent-hover);
}

.post-content strong {
  font-weight: 600;
}

.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
  margin: 1.5rem 0;
  color: var(--text-muted);
  font-style: italic;
}

.post-content code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--line);
  padding: 0.125rem 0.375rem;
  border-radius: 4px;
}

.post-content pre {
  background: var(--line);
  padding: 1rem;
  border-radius: 8px;
  overflow-x: auto;
  margin: 1.5rem 0;
  font-size: 0.875rem;
  line-height: 1.6;
}
.post-content pre code {
  background: none;
  padding: 0;
  border-radius: 0;
}

.post-content ul,
.post-content ol {
  margin: 1rem 0;
  padding-left: 1.5rem;
}
.post-content li {
  margin-bottom: 0.375rem;
}
.post-content img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin: 1.5rem 0;
}

.post-content hr {
  border: none;
  border-top: 1px solid var(--line);
  margin: 2rem 0;
}

/* --- Table of Contents Sidebar --- */
.post-with-toc {
  position: relative;
}

.toc-sidebar {
  display: block;
  position: fixed;
  top: 6rem;
  right: max(calc((100vw - 48rem) / 2 - 240px), 1rem);
  width: 200px;
  max-height: calc(100vh - 8rem);
  overflow-y: auto;
  z-index: 50;
}

.toc-heading {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--line);
}

/* --- TOC Tree List --- */
.toc-list-wrap {
  font-size: 0.8125rem;
  line-height: 1.5;
}

.toc-level {
  list-style: none;
  padding: 0;
  margin: 0;
}

.toc-level .toc-level {
  padding-left: 1rem;
  margin-top: 0.125rem;
}

.toc-item {
  position: relative;
}

/* Level-specific indent via padding */
.toc-item.toc-l1 { }
.toc-item.toc-l2 { padding-left: 0; }
.toc-item.toc-l3 { padding-left: 1rem; }
.toc-item.toc-l4 { padding-left: 2rem; }
.toc-item.toc-l5 { padding-left: 3rem; }
.toc-item.toc-l6 { padding-left: 4rem; }

.toc-link {
  display: block;
  padding: 0.3rem 0;
  color: var(--text-muted);
  text-decoration: none;
  border-left: 2px solid transparent;
  padding-left: 0.75rem;
  transition: color 0.25s ease, border-color 0.25s ease, padding-left 0.25s ease;
  word-break: break-word;
}
.toc-link:hover {
  color: var(--text);
}

.toc-item.toc-active > .toc-link {
  color: var(--accent);
  border-left-color: var(--accent);
  padding-left: 1rem;
}

/* --- TOC active highlight with transition (handled via CSS transitions above) --- */


/* --- Tag Cloud --- */
.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 2rem 0 2rem 0;
}

.tag-cloud-item {
  font-family: var(--font-mono);
  padding: 0.375rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text-muted);
  text-decoration: none;
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  margin: 0 1.2rem 1.2rem 0;
}
.tag-cloud-item:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.tag-count {
  font-size: 0.75rem;
  background: var(--line);
  padding: 0.0625rem 0.375rem;
  border-radius: 999px;
  color: var(--text-muted);
}

.tag-posts {
  margin-bottom: 3rem;
}

/* --- Archive --- */
.archive-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  margin: 2rem 0 2rem 0;
  border-left: 2px solid var(--line);
}

.archive-group {
  padding-left: 1.5rem;
}

.archive-ym {
  font-size: 1.25rem;
  font-weight: 700;
  font-family: var(--font-mono);
  position: relative;
}

.archive-ym::before {
  content: "⬤";
  font-size: 0.5rem;
  position: absolute;
  left: -1.9rem;
  top: 0.6rem;
  color: var(--accent);
}

.archive-posts {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.archive-item {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
}

.archive-day {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-muted);
  white-space: nowrap;
  min-width: 4rem;
}

.archive-link {
  font-size: 0.9375rem;
  color: var(--text);
  text-decoration: none;
  transition: color 0.2s;
}
.archive-link:hover {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* --- Footer --- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 2rem 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  text-align: center;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}

.footer-link {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-link:hover {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  gap: 1rem;
}

.footer-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

.footer-rss {
  display: flex;
  align-items: center;
  color: var(--text-muted);
  transition: color 0.2s;
  padding: 0.25rem;
}
.footer-rss:hover {
  color: var(--accent);
}

.footer-top-btn {
  display: flex;
  align-items: center;
  background: none;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--text-muted);
  padding: 0.375rem;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
}
.footer-top-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
}


/* --- Mobile Drawer --- */
.mobile-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 90;
}
.mobile-overlay.active {
  display: block;
}

.mobile-drawer {
  display: none;
  position: fixed;
  top: 0;
  right: -280px;
  width: 260px;
  height: 100vh;
  background: var(--bg);
  z-index: 100;
  padding: 2rem 1.5rem;
  transition: right 0.3s ease;
  box-shadow: -4px 0 20px rgba(0,0,0,0.1);
  overflow-y: auto;
}
.mobile-drawer.active {
  right: 0;
  display: block;
}

.drawer-close {
  background: none;
  border: none;
  font-size: 1.25rem;
  color: var(--text);
  cursor: pointer;
  margin-bottom: 1.5rem;
  display: block;
  margin-left: auto;
}

.drawer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.drawer-nav a {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text);
  text-decoration: none;
  transition: color 0.2s;
}
.drawer-nav a:hover {
  color: var(--accent);
}

.drawer-actions {
  margin-top: 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}


.drawer-links {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.drawer-links a {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text-muted);
  text-decoration: none;
}
.drawer-links a:hover {
  color: var(--accent);
}
.drawer-theme-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.75rem 0;
  margin-top: 0.5rem;
  border-radius: 0;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: color 0.2s;
}
.drawer-theme-btn {
  margin-bottom: 0.25rem;
}
.drawer-theme-btn:hover {
  color: var(--accent);
}
.drawer-theme-btn svg {
  width: 1.25rem;
  height: 1.25rem;
}
.drawer-theme-label {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
}

.drawer-scheme-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.75rem 0;
  border-radius: 0;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: color 0.2s;
  background: none;
  border: none;
  flex-shrink: 0;
}
.drawer-scheme-btn:hover {
  color: var(--accent);
}
.drawer-scheme-btn svg {
  width: 1.25rem;
  height: 1.25rem;
}

.drawer-btn-label {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
}



/* --- Responsive --- */
@media (max-width: 1023px) {
  .toc-sidebar {
    display: none;
  }
}

@media (max-width: 768px) {
  .desktop-theme-btn,
  .desktop-scheme-btn {
    display: none;
  }
  .layout-container {
    padding: 0 1rem;
  }
  .header-nav {
    display: none;
  }
  .menu-btn {
    display: block;
  }
  .hero-title {
    font-size: 2.25rem;
  }
  .post-full-title {
    font-size: 1.5rem;
  }
  .section-title {
    font-size: 1.375rem;
  }
  .filter-bar {
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 0.5rem;
    -webkit-overflow-scrolling: touch;
  }
  .post-meta {
    font-size: 0.75rem;
  }
  .archive-item {
    flex-direction: column;
    gap: 0.25rem;
  }
  .mobile-drawer {
    display: block;
  }
}

@media (max-width: 480px) {
  .section-header {
    flex-direction: column;
    gap: 0.5rem;
  }
  .pagination {
    gap: 0.5rem;
  }
}