:root {
  --color-bg: #282828;
  --color-text: #ebdbb2;
  --color-link: #458588;
  --color-link-visited: #7c9c94;
  --color-link-hover: #83a598;
  --color-border: #3c3836;
  --color-code-bg: #3c3836;
  --color-header-bg: #282828;
  --color-hover-bg: rgba(69, 133, 136, 0.1);
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-serif: Charter, 'Bitstream Charter', 'Sitka Text', Cambria, Georgia, serif;
  --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Monaco, "Courier New", monospace;
  --max-width: 900px;
  --header-height: 70px;
  --transition-fast: 0.2s ease;
}

html[data-theme="light"] {
  --color-bg: #fbf1c7;
  --color-text: #3c3836;
  --color-link: #076678;
  --color-link-visited: #5f8f8f;
  --color-link-hover: #458588;
  --color-border: #d5c4a1;
  --color-code-bg: #eee8d5;
  --color-header-bg: #fbf1c7;
  --color-hover-bg: rgba(7, 102, 120, 0.08);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--color-link);
  text-decoration: none;
  transition: color var(--transition-fast);
  position: relative;
}

a:hover {
  color: var(--color-link-hover);
}

a:visited {
  color: var(--color-link-visited);
}

a:not(.post-link):not(.footer-link)::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background-color: var(--color-link);
  transition: width var(--transition-fast);
}

a:not(.post-link):not(.footer-link):hover::after {
  width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  background-color: var(--color-header-bg);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.site-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: -0.02em;
  font-family: var(--font-serif);
  display: flex;
  flex-direction: column;
  line-height: 1.3;
}

.site-subtitle {
  font-size: 0.7rem;
  font-weight: 600;
  opacity: 0.8;
  letter-spacing: 0.05em;
  margin-top: 2px;
}

.site-title:hover {
  color: var(--color-link);
}

.site-title.is-active {
  color: var(--color-link);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-link {
  font-size: 0.9rem;
  color: var(--color-text);
  opacity: 0.8;
  transition: opacity var(--transition-fast), color var(--transition-fast);
}

.nav-link:hover {
  opacity: 1;
  color: var(--color-link);
}

.nav-link.is-active {
  opacity: 1;
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.rss-link {
  display: flex;
  align-items: center;
  opacity: 0.6;
  transition: opacity var(--transition-fast);
}

.rss-link:hover {
  opacity: 1;
  color: var(--color-link);
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.25rem;
  color: var(--color-text);
  opacity: 0.7;
  transition: opacity var(--transition-fast), color var(--transition-fast);
  display: flex;
  align-items: center;
}

.theme-toggle:hover {
  opacity: 1;
  color: var(--color-link);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
}

.sun-icon {
  display: none;
}

.moon-icon {
  display: block;
}

html[data-theme="light"] .sun-icon {
  display: block;
}

html[data-theme="light"] .moon-icon {
  display: none;
}

.main-content {
  flex: 1;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

.home-container {
  animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.intro-section {
  margin-bottom: 2rem;
}

.social-links {
  display: flex;
  gap: 1rem;
}

.social-link {
  color: var(--color-text);
  opacity: 0.6;
  transition: opacity var(--transition-fast), color var(--transition-fast);
}

.social-link:hover {
  opacity: 1;
  color: var(--color-link);
}

.home-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.recent-post-section {
  margin-bottom: 2.5rem;
}

.post-card {
  position: relative;
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background-color: var(--color-hover-bg);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.post-card:hover {
  border-color: var(--color-link);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.post-card-label {
  position: absolute;
  top: -10px;
  left: 12px;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-link);
  background-color: var(--color-bg);
  padding: 0 6px;
}

.post-desc {
  font-size: 0.9rem;
  color: var(--color-text);
  opacity: 0.7;
  margin-top: 0.25rem;
  line-height: 1.5;
}

.posts-link {
  color: var(--color-link);
  font-weight: 500;
}

.posts-link:hover {
  color: var(--color-link-hover);
}

.projects-grid {
  display: grid;
  gap: 1.5rem;
}

.project-card {
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  transition: background-color var(--transition-fast);
}

.project-card:hover {
  background-color: var(--color-hover-bg);
}

.project-name {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-text);
}

.project-desc {
  font-size: 0.9rem;
  color: var(--color-text);
  opacity: 0.75;
  margin-bottom: 1rem;
  line-height: 1.6;
}

.project-link {
  font-size: 0.85rem;
  font-weight: 500;
}

.intro-text {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--color-text);
  opacity: 0.85;
}

.page-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.posts-layout {
  display: grid;
  grid-template-columns: 1fr 180px;
  gap: 3rem;
  align-items: start;
}

.posts-main {
  min-width: 0;
}

.posts-sidebar {
  position: sticky;
  top: 100px;
}

.sidebar-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text);
  opacity: 0.5;
  margin-bottom: 1rem;
  font-family: var(--font-serif);
}

.sidebar-tags {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.sidebar-tag {
  background: none;
  border: none;
  font-size: 0.85rem;
  color: var(--color-text);
  opacity: 0.5;
  cursor: pointer;
  padding: 0.25rem 0;
  font-family: var(--font-sans);
  text-align: left;
  transition: opacity var(--transition-fast), color var(--transition-fast);
}

.sidebar-tag:hover {
  opacity: 0.8;
  color: var(--color-link);
}

.sidebar-tag.is-active {
  opacity: 1;
  color: var(--color-link);
  font-weight: 600;
}

.section-title {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text);
  opacity: 0.6;
  margin-bottom: 1.5rem;
  font-family: var(--font-serif);
}

.post-list {
  list-style: none;
}

.post-item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 1rem;
  margin: 0 -1rem;
  border-bottom: 1px solid var(--color-border);
  border-radius: 8px;
  transition: background-color var(--transition-fast);
}

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

.post-item:hover {
  background-color: var(--color-hover-bg);
}

.post-item.is-hidden {
  display: none;
}

.post-date {
  font-size: 0.85rem;
  color: var(--color-text);
  opacity: 0.6;
  font-variant-numeric: tabular-nums;
}

.post-title {
  font-size: 1.15rem;
  font-weight: 500;
  line-height: 1.4;
}

.post-link {
  color: var(--color-text);
  transition: color var(--transition-fast);
}

.post-link:hover {
  color: var(--color-link);
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.25rem;
}

.post-tag {
  background: none;
  border: none;
  font-size: 0.7rem;
  color: var(--color-text);
  opacity: 0.45;
  cursor: pointer;
  padding: 0;
  font-family: var(--font-sans);
  letter-spacing: 0.02em;
  transition: opacity var(--transition-fast), color var(--transition-fast);
}

.post-tag:hover,
.post-tag.is-active {
  opacity: 1;
  color: var(--color-link);
}

.post-tag-static {
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--color-text);
  opacity: 0.55;
  letter-spacing: 0.02em;
  margin-right: 0.4rem;
}

.post {
  animation: fadeIn 0.5s ease;
}

.post-header {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

.post-title {
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.post-date {
  font-size: 0.9rem;
  color: var(--color-text);
  opacity: 0.7;
}

.post-content {
  font-size: 1.05rem;
  line-height: 1.8;
}

.post-content p {
  margin-bottom: 1.5rem;
}

.post-content h1,
.post-content h2,
.post-content h3 {
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  font-family: var(--font-serif);
}

.post-content h2 {
  font-size: 1.35rem;
}

.post-content h3 {
  font-size: 1.15rem;
}

.post-content ul,
.post-content ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.post-content li {
  margin-bottom: 0.5rem;
}

.post-content img {
  max-width: 100%;
  height: auto;
  border-radius: 4px;
  margin: 1.5rem 0;
}

.post-content a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.post-content a:hover {
  text-decoration: none;
}

.post-content code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background-color: var(--color-code-bg);
  padding: 0.2em 0.4em;
  border-radius: 3px;
}

.post-content pre {
  background-color: var(--color-code-bg);
  padding: 1rem;
  border-radius: 6px;
  overflow-x: auto;
  margin: 1.5rem 0;
}

.post-content pre code {
  background-color: transparent;
  padding: 0;
  font-size: 0.85rem;
  line-height: 1.6;
}

.post-content blockquote {
  border-left: 3px solid var(--color-link);
  padding-left: 1rem;
  margin: 1.5rem 0;
  color: var(--color-text);
  opacity: 0.8;
  font-style: italic;
}

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

.post-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

.back-link {
  font-size: 0.95rem;
  font-weight: 500;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 1.5rem;
  margin-top: auto;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  text-align: center;
}

.footer-copyright {
  font-size: 0.85rem;
  color: var(--color-text);
  opacity: 0.6;
  margin-bottom: 0.5rem;
}

.footer-tagline {
  font-size: 0.9rem;
  color: var(--color-text);
  opacity: 0.5;
  margin-bottom: 1rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
}

.footer-link {
  font-size: 0.85rem;
  color: var(--color-text);
  opacity: 0.7;
  transition: color var(--transition-fast), opacity var(--transition-fast);
}

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

@media (max-width: 600px) {
  html {
    font-size: 15px;
  }

  .header-inner {
    padding: 1rem;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }

  .site-nav {
    width: 100%;
    justify-content: space-between;
  }

  .main-content {
    padding: 1.5rem 1rem;
  }

  .post-title {
    font-size: 1.5rem;
  }

  .footer-links {
    flex-direction: column;
    gap: 0.75rem;
  }

  .posts-layout {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .posts-sidebar {
    position: static;
    order: -1;
  }

  .sidebar-tags {
    flex-direction: row;
    flex-wrap: wrap;
  }
}