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

:root {
  --color-bg: #f8f6f1;
  --color-text: #1a1a1a;
  --color-text-light: #555;
  --color-accent: #111;
  --color-accent-hover: #444;
  --color-border: #eaeaea;
  --color-code-bg: #f4f4f4;
  --color-tag-bg: #f0f0f0;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", "Fira Code", Consolas, monospace;
  --max-width: 640px;
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 2rem;
  --space-xl: 3.5rem;
}

[data-theme="dark"] {
  --color-bg: #1a1a1a;
  --color-text: #e0e0e0;
  --color-text-light: #999;
  --color-accent: #e0e0e0;
  --color-accent-hover: #bbb;
  --color-border: #333;
  --color-code-bg: #252525;
  --color-tag-bg: #2a2a2a;
}

html {
  font-size: 17px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.01em;
  word-spacing: 0.05em;
}

body {
  font-family: var(--font-sans);
  font-weight: 500;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.75;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--color-text);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: opacity 0.15s;
}

a:hover {
  opacity: 0.6;
  text-decoration: underline;
}

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

/* ===== Header / Nav ===== */
.site-header {
  padding: var(--space-lg) 0;
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.site-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.site-title:hover {
  text-decoration: none;
  opacity: 0.6;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: var(--space-lg);
}

.nav-links a {
  font-size: 0.85rem;
  color: var(--color-text-light);
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--color-text);
  opacity: 1;
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--color-text-light);
  padding: 0;
  font-family: var(--font-sans);
  transition: color 0.15s;
}

.theme-toggle:hover {
  color: var(--color-text);
}

/* ===== Main Content ===== */
.content-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-xl) var(--space-md);
  flex: 1;
  width: 100%;
}

/* ===== Hero ===== */
.hero {
  margin-bottom: var(--space-xl);
}

.hero h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-xs);
}

.hero-subtitle {
  color: var(--color-text-light);
  font-size: 1rem;
}

/* ===== Post List ===== */
.posts-list h2 {
  font-size: 0.8rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-light);
  margin-bottom: var(--space-lg);
}

.post-card {
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

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

.post-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: var(--space-xs);
  line-height: 1.4;
  letter-spacing: -0.02em;
}

.post-card h3 a {
  text-decoration: none;
}

.post-card h3 a:hover {
  text-decoration: underline;
}

.post-meta {
  font-size: 0.8rem;
  color: var(--color-text-light);
  margin-bottom: var(--space-sm);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-sm);
}

.post-excerpt {
  color: var(--color-text-light);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ===== Tags ===== */
.tag {
  display: inline-block;
  color: var(--color-text-light);
  padding: 0 0.5em;
  border: 1px solid var(--color-border);
  border-radius: 9999px;
  font-size: 0.75rem;
  text-decoration: none;
  background: transparent;
  line-height: 1.8;
}

.tag:hover {
  border-color: #ccc;
  color: var(--color-text);
  text-decoration: none;
  opacity: 1;
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
}

.tag-large {
  font-size: 0.85rem;
  padding: 0.3em 0.7em;
}

.tag-count {
  opacity: 0.5;
}

/* ===== Single Post ===== */
.post-header {
  margin-bottom: var(--space-xl);
}

.post-title {
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-sm);
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
}

/* ===== Prose (article body) ===== */
.prose h2 {
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
}

.prose h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
}

.prose p {
  margin-bottom: var(--space-md);
  letter-spacing: 0;
  word-spacing: 0.06em;
}

.prose ul,
.prose ol {
  margin-bottom: var(--space-md);
  padding-left: var(--space-lg);
}

.prose li {
  margin-bottom: var(--space-xs);
}

.prose blockquote {
  border-left: 2px solid var(--color-border);
  padding-left: var(--space-md);
  margin: var(--space-lg) 0;
  color: var(--color-text-light);
  font-style: italic;
}

.prose code {
  font-family: var(--font-mono);
  background: var(--color-code-bg);
  padding: 0.15em 0.35em;
  border-radius: 4px;
  font-size: 0.85em;
}

.prose pre {
  background: var(--color-code-bg);
  padding: var(--space-md);
  border-radius: 8px;
  overflow-x: auto;
  margin-bottom: var(--space-md);
}

.prose pre code {
  background: none;
  padding: 0;
  font-size: 0.82rem;
  line-height: 1.6;
}

.prose hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-xl) 0;
}

.prose img {
  border-radius: 8px;
  margin: var(--space-md) 0;
}

/* ===== Post Navigation ===== */
.post-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  margin-top: var(--space-xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
}

.post-nav-link {
  font-size: 0.85rem;
}

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

/* ===== Search ===== */
.nav-search {
  flex-shrink: 1;
  min-width: 0;
}

#nav-search-input {
  width: 140px;
  padding: 0.3rem 0;
  font-size: 0.85rem;
  border: none;
  border-bottom: 1px solid var(--color-border);
  font-family: var(--font-sans);
  background: transparent;
  color: var(--color-text);
  transition: border-color 0.15s, width 0.2s;
}

#nav-search-input::placeholder {
  color: #bbb;
}

#nav-search-input:focus {
  outline: none;
  border-bottom-color: var(--color-text);
  width: 200px;
}

.search-overlay-content {
  padding-top: var(--space-xl);
}

#search-results {
  margin-top: var(--space-md);
}

.no-results {
  color: var(--color-text-light);
}

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
  margin-top: auto;
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-text-light);
}

/* ===== Responsive ===== */
@media (max-width: 600px) {
  html {
    font-size: 16px;
  }

  .nav-container {
    flex-direction: column;
    align-items: flex-start;
  }

  .nav-links {
    gap: var(--space-md);
  }

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

  .hero h1 {
    font-size: 1.5rem;
  }

  .content-container {
    padding: var(--space-lg) var(--space-md);
  }

  .post-nav {
    flex-direction: column;
  }

  .post-nav-link.next {
    text-align: left;
  }
}