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

/* Light theme (default) */
:root {
  --bg: #FFFAF5;
  --surface: #F5F0EB;
  --border: #E5DDD4;
  --text: #1A1A1A;
  --text-muted: #6B6560;
  --heading: #2D2B27;
  --accent: #D97706;
  --accent-hover: #B45309;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'Fira Code', 'Cascadia Code', monospace;
  --max-width: 720px;
}

/* Dark theme */
[data-theme="dark"] {
  --bg: #0a0a0f;
  --surface: #12121a;
  --border: #1e1e2e;
  --text: #e0e0e8;
  --text-muted: #8888a0;
  --heading: #e0e0e8;
  --accent: #D97706;
  --accent-hover: #F59E0B;
}

/* Selection */
::selection {
  background: var(--accent);
  color: #fff;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 17px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3 { color: var(--heading); }

a { color: var(--accent); text-decoration: none; transition: color .2s; }
a:hover { color: var(--accent-hover); }

/* Header */
.site-header {
  border-bottom: 1px solid var(--border);
  padding: 1.5rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 960px;
  width: 100%;
  margin: 0 auto;
}

.site-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--heading);
  letter-spacing: -0.02em;
}

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

.site-nav a {
  color: var(--text-muted);
  font-size: 0.9rem;
}
.site-nav a:hover { color: var(--text); }

/* Theme toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.4rem;
  border-radius: 6px;
  font-size: 1.1rem;
  line-height: 1;
  transition: color .2s, border-color .2s;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
}
.theme-toggle:hover { color: var(--text); border-color: var(--text-muted); }

/* Show moon in light mode, sun in dark mode */
:root .theme-toggle .icon-sun { display: none; }
:root .theme-toggle .icon-moon { display: inline; }
[data-theme="dark"] .theme-toggle .icon-sun { display: inline; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* Main */
main {
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  flex: 1;
}

/* Post list */
.post-list { list-style: none; }

.post-item {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--border);
}

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

.post-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 0.4rem;
}

.post-item h2 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
}

.post-item p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Tags */
.post-tags { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-top: 0.5rem; }

.tag {
  display: inline-block;
  font-size: 0.75rem;
  padding: 0.15em 0.6em;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-weight: 500;
  text-decoration: none;
  transition: opacity .2s;
}
.tag:hover { opacity: 0.8; color: #fff; }

/* Single post */
.post-header { margin-bottom: 2rem; }

.post-header h1 {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.02em;
}

.reading-time {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.3rem;
}

/* TOC */
.toc-wrapper {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin-bottom: 2rem;
}

.toc-wrapper h2 {
  font-size: 0.95rem;
  margin-bottom: 0.5rem;
  color: var(--text-muted);
}

.toc-wrapper ul { margin: 0 0 0 1.2rem; }
.toc-wrapper li { margin-bottom: 0.3rem; font-size: 0.9rem; }

/* Post content */
.post-content h2 { font-size: 1.4rem; margin: 2rem 0 0.8rem; font-weight: 600; }
.post-content h3 { font-size: 1.15rem; margin: 1.5rem 0 0.6rem; font-weight: 600; }
.post-content p { margin-bottom: 1.2rem; }
.post-content ul, .post-content ol { margin: 0 0 1.2rem 1.5rem; }
.post-content li { margin-bottom: 0.4rem; }

.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding: 0.5rem 1rem;
  margin: 1.5rem 0;
  color: var(--text-muted);
  background: var(--surface);
  border-radius: 0 6px 6px 0;
}

.post-content code {
  font-family: var(--font-mono);
  background: var(--surface);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-size: 0.9em;
}

.post-content pre {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  overflow-x: auto;
  margin-bottom: 1.5rem;
}

.post-content pre code {
  background: none;
  padding: 0;
}

/* Post article tags */
.post-article-tags {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

.post-article-tags .label {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-right: 0.5rem;
}

/* Post navigation */
.post-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  gap: 1rem;
}

.post-nav a {
  font-size: 0.9rem;
  max-width: 45%;
}

.post-nav .prev::before { content: "\2190 "; }
.post-nav .next::after { content: " \2192"; }

/* Giscus */
.giscus-wrapper {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

/* GitHub star badge */
.star-badge {
  margin-bottom: 1.5rem;
}

/* Tags page */
.tags-page h2 {
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

.tags-page ul { list-style: none; margin-bottom: 1rem; }
.tags-page li { padding: 0.3rem 0; }

/* 404 page */
.not-found { text-align: center; padding: 4rem 0; }
.not-found h1 { font-size: 4rem; margin-bottom: 1rem; }
.not-found p { color: var(--text-muted); margin-bottom: 1.5rem; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 1.5rem 2rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* Rouge syntax highlighting - light theme (GitHub-style) */
.highlight .c, .highlight .c1, .highlight .cm, .highlight .cs { color: #6a737d; font-style: italic; }
.highlight .k, .highlight .kd, .highlight .kn, .highlight .kp, .highlight .kr { color: #d73a49; }
.highlight .kt { color: #6f42c1; }
.highlight .s, .highlight .s1, .highlight .s2, .highlight .sb, .highlight .sc, .highlight .sh { color: #032f62; }
.highlight .si { color: #032f62; }
.highlight .na { color: #6f42c1; }
.highlight .nb { color: #005cc5; }
.highlight .nc { color: #6f42c1; }
.highlight .nf, .highlight .fm { color: #6f42c1; }
.highlight .nn { color: #005cc5; }
.highlight .no { color: #005cc5; }
.highlight .ni { color: #24292e; }
.highlight .ne { color: #d73a49; }
.highlight .o, .highlight .ow { color: #d73a49; }
.highlight .p { color: #24292e; }
.highlight .mi, .highlight .mf, .highlight .mh, .highlight .mo { color: #005cc5; }

/* Rouge syntax highlighting - dark theme */
[data-theme="dark"] .highlight .c, [data-theme="dark"] .highlight .c1,
[data-theme="dark"] .highlight .cm, [data-theme="dark"] .highlight .cs { color: #6a9955; font-style: italic; }
[data-theme="dark"] .highlight .k, [data-theme="dark"] .highlight .kd,
[data-theme="dark"] .highlight .kn, [data-theme="dark"] .highlight .kp,
[data-theme="dark"] .highlight .kr { color: #c586c0; }
[data-theme="dark"] .highlight .kt { color: #4ec9b0; }
[data-theme="dark"] .highlight .s, [data-theme="dark"] .highlight .s1,
[data-theme="dark"] .highlight .s2, [data-theme="dark"] .highlight .sb,
[data-theme="dark"] .highlight .sc, [data-theme="dark"] .highlight .sh { color: #ce9178; }
[data-theme="dark"] .highlight .si { color: #ce9178; }
[data-theme="dark"] .highlight .na { color: #9cdcfe; }
[data-theme="dark"] .highlight .nb { color: #dcdcaa; }
[data-theme="dark"] .highlight .nc { color: #4ec9b0; }
[data-theme="dark"] .highlight .nf, [data-theme="dark"] .highlight .fm { color: #dcdcaa; }
[data-theme="dark"] .highlight .nn { color: #4ec9b0; }
[data-theme="dark"] .highlight .no { color: #4fc1ff; }
[data-theme="dark"] .highlight .ni { color: #e0e0e8; }
[data-theme="dark"] .highlight .ne { color: #c586c0; }
[data-theme="dark"] .highlight .o, [data-theme="dark"] .highlight .ow { color: #d4d4d4; }
[data-theme="dark"] .highlight .p { color: #d4d4d4; }
[data-theme="dark"] .highlight .mi, [data-theme="dark"] .highlight .mf,
[data-theme="dark"] .highlight .mh, [data-theme="dark"] .highlight .mo { color: #b5cea8; }

/* Responsive */
@media (max-width: 600px) {
  .site-header { flex-direction: column; gap: 0.75rem; }
  .site-nav { gap: 1rem; }
  main { padding: 2rem 1rem; }
  .post-header h1 { font-size: 1.5rem; }
  .post-nav { flex-direction: column; }
  .post-nav a { max-width: 100%; }
}