/* =========================================================================
   GitHub Researcher — GitHub Primer design system
   Shared stylesheet for all pages (index, daily, projects, trends, detail)
   ========================================================================= */

:root {
  /* GitHub Primer color tokens */
  --canvas-default: #ffffff;
  --canvas-subtle: #f6f8fa;
  --canvas-inset: #eaeef2;
  --border-default: #d0d7de;
  --border-muted: #d8dee4;
  --fg-default: #1f2328;
  --fg-muted: #656d76;
  --fg-subtle: #6e7781;
  --accent-fg: #0969da;
  --accent-emphasis: #0969da;
  --accent-subtle: #ddf4ff;
  --success-fg: #1a7f37;
  --success-emphasis: #1f883d;
  --success-subtle: #dafbe1;
  --attention-fg: #9a6700;
  --attention-subtle: #fff8c5;
  --danger-fg: #d1242f;
  --done-fg: #8250df;
  --done-subtle: #fbefff;
  --header-bg: #ffffff;
  --header-fg: #1f2328;
  --header-logo: #0969da;

  /* Button tokens (GitHub) */
  --btn-bg: #f6f8fa;
  --btn-hover-bg: #f3f4f6;
  --btn-border: rgba(31, 35, 40, 0.15);
  --btn-primary-bg: #1f883d;
  --btn-primary-hover-bg: #1a7f37;
  --btn-primary-border: rgba(31, 35, 40, 0.15);

  /* Typography */
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  /* Radius / shadow */
  --radius: 8px;
  --radius-sm: 6px;
  --radius-xs: 4px;
  --shadow-sm: 0 1px 0 rgba(31, 35, 40, 0.04);
  --shadow-md: 0 3px 6px rgba(140, 149, 159, 0.15);
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-body);
  background: var(--canvas-default);
  color: var(--fg-default);
  line-height: 1.6;
  min-height: 100vh;
  font-size: 14px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: var(--accent-fg); text-decoration: none; }
a:hover { text-decoration: underline; }

/* =========================================================================
   Top navigation (light, GitHub Primer style, 56px)
   ========================================================================= */
.nav {
  background: var(--canvas-default);
  color: var(--fg-default);
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 0 24px;
  border-bottom: 1px solid var(--border-default);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 16px;
  color: var(--fg-default);
  text-decoration: none;
}
.nav-brand:hover { text-decoration: none; color: var(--accent-fg); }
.nav-brand svg { width: 26px; height: 26px; flex-shrink: 0; color: var(--fg-default); }
.nav-links {
  display: flex;
  align-items: center;
  gap: 2px;
}
.nav-links a {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  color: var(--fg-muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: background 0.15s, color 0.15s;
}
.nav-links a:hover { background: var(--accent-subtle); color: var(--accent-fg); text-decoration: none; }
.nav-links a svg { width: 16px; height: 16px; }
.nav-links a.active { background: var(--accent-subtle); color: var(--accent-fg); }

/* =========================================================================
   Layout container
   ========================================================================= */
.container { max-width: 1100px; margin: 0 auto; padding: 40px 24px 60px; }

/* =========================================================================
   Hero (index)
   ========================================================================= */
.hero { text-align: center; padding: 56px 0 44px; }

/* Meta line: green dot · date · separator · status — no pill, no animation */
.hero-meta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 24px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--fg-muted);
}
.hero-meta-dot {
  width: 8px; height: 8px;
  background: var(--success-emphasis);
  border-radius: 50%;
  display: inline-block;
}
.hero-meta-date { color: var(--fg-default); font-weight: 500; }
.hero-meta-sep { color: var(--border-default); }
.hero-meta-status { color: var(--fg-muted); }
.hero-title {
  font-size: 40px;
  font-weight: 600;
  letter-spacing: -0.5px;
  color: var(--fg-default);
  margin-bottom: 16px;
  line-height: 1.15;
}
.hero-subtitle {
  font-size: 16px;
  color: var(--fg-muted);
  max-width: 640px;
  margin: 0 auto 32px;
  line-height: 1.65;
}
.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
}

/* =========================================================================
   Buttons (GitHub Primer)
   ========================================================================= */
.btn-primary, .btn-secondary, .btn-outline, .btn-github, .btn-dark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 16px;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 14px;
  font-family: var(--font-body);
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
  line-height: 1.5;
}
.btn-primary:hover, .btn-secondary:hover, .btn-outline:hover, .btn-github:hover, .btn-dark:hover { text-decoration: none; }

/* Dark CTA — high contrast, GitHub Primer inverted */
.btn-dark {
  background: #1f2328;
  color: #ffffff;
  border-color: rgba(31,35,40,0.15);
  padding: 8px 18px;
  font-weight: 500;
}
.btn-dark:hover {
  background: #2a2f36;
  color: #ffffff;
  border-color: rgba(31,35,40,0.2);
}
.btn-dark svg { transition: transform 0.18s ease; }
.btn-dark:hover svg { transform: translateX(2px); }

/* Primary (green CTA) */
.btn-primary {
  background: var(--btn-primary-bg);
  color: #ffffff;
  border-color: rgba(31,35,40,0.15);
  box-shadow: 0 1px 0 rgba(31,35,40,0.1);
}
.btn-primary:hover { background: var(--btn-primary-hover-bg); color: #ffffff; border-color: rgba(31,35,40,0.15); }

/* Secondary (default gray) */
.btn-secondary {
  background: var(--btn-bg);
  color: var(--fg-default);
  border-color: var(--btn-border);
  box-shadow: var(--shadow-sm);
}
.btn-secondary:hover { background: var(--btn-hover-bg); }

/* Outline (white / accent link style) */
.btn-outline {
  background: #fff;
  color: var(--accent-fg);
  border-color: var(--border-default);
}
.btn-outline:hover { background: var(--accent-subtle); border-color: #54aeff; }

/* Small GitHub button inside cards */
.btn-github {
  padding: 5px 12px;
  font-size: 12px;
  background: var(--btn-bg);
  color: var(--fg-default);
  border: 1px solid var(--btn-border);
  box-shadow: var(--shadow-sm);
}
.btn-github:hover { background: var(--btn-hover-bg); border-color: var(--border-default); }
.btn-github svg { width: 14px; height: 14px; }

/* =========================================================================
   Stats row
   ========================================================================= */
.stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 44px;
}
.stat-card {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  padding: 22px 18px 20px;
  text-align: center;
  transition: border-color 0.15s, box-shadow 0.15s, transform 0.15s;
}
.stat-card:hover {
  border-color: #54aeff;
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}
/* Primary stat — inverted, hero number */
.stat-card-primary {
  background: #1f2328;
  border-color: #1f2328;
  color: #ffffff;
}
.stat-card-primary:hover {
  border-color: #2a2f36;
  box-shadow: 0 6px 14px rgba(31,35,40,0.18);
}
.stat-card-primary .stat-icon { color: #8b949e; }
.stat-card-primary .stat-number { color: #ffffff; }
.stat-card-primary .stat-label { color: #8b949e; }
.stat-icon {
  width: 36px; height: 36px;
  margin: 0 auto 12px;
  color: var(--fg-muted);
  display: flex; align-items: center; justify-content: center;
}
.stat-number {
  font-size: 28px;
  font-weight: 600;
  color: var(--fg-default);
  margin-bottom: 4px;
  font-family: var(--font-mono);
  letter-spacing: -0.5px;
  line-height: 1.1;
}
.stat-label { font-size: 12px; color: var(--fg-muted); font-weight: 400; }

/* =========================================================================
   Section headers
   ========================================================================= */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-default);
}
.section-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 600;
  color: var(--fg-default);
}
.section-title .icon { font-size: 16px; }
.section-link {
  font-size: 13px;
  color: var(--accent-fg);
  text-decoration: none;
  font-weight: 500;
}
.section-link:hover { text-decoration: underline; }

/* =========================================================================
   Cards (GitHub repo card style)
   ========================================================================= */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 16px;
  margin-bottom: 44px;
}
.card {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  padding: 20px;
  transition: border-color 0.15s, box-shadow 0.15s;
  text-decoration: none;
  color: inherit;
  display: block;
  height: 100%;
}
.card:hover {
  border-color: #54aeff;
  box-shadow: var(--shadow-md);
  text-decoration: none;
}
.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 12px;
}
.card-emoji { font-size: 24px; line-height: 1; }
.card-stars {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: var(--success-subtle);
  color: var(--success-fg);
  padding: 3px 10px;
  border-radius: 2em;
  font-size: 12px;
  font-weight: 600;
  font-family: var(--font-mono);
  border: 1px solid #aceebb;
}
.card-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--accent-fg);
}
.card-title:hover { text-decoration: underline; }
.card-desc {
  font-size: 13px;
  color: var(--fg-muted);
  line-height: 1.55;
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.card-actions { display: flex; align-items: center; gap: 8px; margin-top: 10px; }

/* =========================================================================
   Tags / Labels (GitHub label style)
   ========================================================================= */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 2px 10px;
  border-radius: 2em;
  font-size: 12px;
  font-weight: 500;
  border: 1px solid transparent;
  line-height: 1.5;
}
.tag-purple { background: var(--done-subtle); color: var(--done-fg); border-color: #d8b9fe; }
.tag-cyan   { background: var(--accent-subtle); color: var(--accent-fg); border-color: #54aeff; }
.tag-green  { background: var(--success-subtle); color: var(--success-fg); border-color: #aceebb; }
.tag-orange { background: var(--attention-subtle); color: var(--attention-fg); border-color: #d4a72c; }

/* =========================================================================
   Trend list (index + trends page)
   ========================================================================= */
.trend-list {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 44px;
}
.trend-item {
  display: flex;
  align-items: center;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-muted);
  gap: 14px;
  transition: background 0.1s;
}
.trend-item:last-child { border-bottom: none; }
.trend-item:hover { background: var(--canvas-subtle); }
.trend-rank {
  width: 24px; height: 24px;
  border-radius: 2em;
  background: var(--canvas-subtle);
  color: var(--fg-muted);
  border: 1px solid var(--border-default);
  font-size: 12px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-family: var(--font-mono);
}
.trend-rank.top { background: #fff8c5; color: var(--attention-fg); border-color: #d4a72c; }
.trend-content { flex: 1; min-width: 0; }
.trend-title { font-size: 14px; font-weight: 600; color: var(--fg-default); margin-bottom: 2px; }
.trend-meta { font-size: 12px; color: var(--fg-muted); }
.trend-score {
  padding: 3px 12px;
  border-radius: 2em;
  font-size: 12px;
  font-weight: 600;
  background: var(--canvas-subtle);
  color: var(--fg-muted);
  border: 1px solid var(--border-default);
  flex-shrink: 0;
  font-family: var(--font-mono);
}
.trend-score.high { background: var(--success-subtle); color: var(--success-fg); border-color: #aceebb; }

/* =========================================================================
   Brief card (today's verdict, index)
   ========================================================================= */
.brief-card {
  background: var(--canvas-subtle);
  border: 1px solid var(--border-default);
  border-left: 4px solid var(--accent-fg);
  border-radius: var(--radius);
  padding: 28px 32px;
  margin-bottom: 44px;
}
.brief-date {
  font-size: 12px;
  color: var(--fg-muted);
  margin-bottom: 6px;
  font-weight: 500;
  font-family: var(--font-mono);
}
.brief-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--fg-default);
  margin-bottom: 12px;
  line-height: 1.35;
}
.brief-text {
  font-size: 14px;
  color: var(--fg-default);
  line-height: 1.65;
  max-width: 740px;
  margin-bottom: 20px;
}
.brief-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent-fg);
  text-decoration: none;
  font-weight: 500;
  font-size: 14px;
}
.brief-cta:hover { text-decoration: underline; }

/* =========================================================================
   Category pills (index)
   ========================================================================= */
.category-row { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 44px; }
.category-pill {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--canvas-subtle);
  border: 1px solid var(--border-default);
  border-radius: 2em;
  font-size: 13px;
  font-weight: 500;
  color: var(--fg-default);
  text-decoration: none;
  transition: all 0.15s;
}
.category-pill:hover {
  background: var(--accent-subtle);
  color: var(--accent-fg);
  border-color: #54aeff;
  text-decoration: none;
}
.category-pill .emoji { font-size: 14px; }

/* =========================================================================
   Filter bar (GitHub-style search/filter)
   ========================================================================= */
.filter-bar {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin-bottom: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  align-items: center;
}
.filter-group { display: flex; align-items: center; gap: 8px; }
.filter-group label {
  font-size: 13px;
  font-weight: 600;
  color: var(--fg-default);
  white-space: nowrap;
}
.filter-group select, .filter-group input {
  padding: 6px 12px;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  font-size: 13px;
  background: var(--canvas-default);
  color: var(--fg-default);
  outline: none;
  transition: border-color 0.15s, box-shadow 0.15s;
  font-family: var(--font-body);
}
.filter-group select:focus, .filter-group input:focus {
  border-color: var(--accent-fg);
  box-shadow: 0 0 0 3px rgba(9, 105, 218, 0.3);
}
.filter-group input[type="text"] { min-width: 200px; }
.filter-count {
  font-size: 13px;
  color: var(--fg-muted);
  margin-left: auto;
  font-weight: 500;
}
.filter-empty {
  text-align: center;
  padding: 48px 20px;
  color: var(--fg-muted);
  font-size: 14px;
  display: none;
}

/* =========================================================================
   Tables (GitHub-style)
   ========================================================================= */
.gh-table {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 44px;
}
.gh-table table { width: 100%; border-collapse: collapse; }
.gh-table th {
  background: var(--canvas-subtle);
  color: var(--fg-default);
  padding: 12px 18px;
  text-align: left;
  font-size: 13px;
  font-weight: 600;
  border-bottom: 1px solid var(--border-default);
}
.gh-table td {
  padding: 12px 18px;
  border-bottom: 1px solid var(--border-muted);
  font-size: 14px;
}
.gh-table tr:last-child td { border-bottom: none; }
.gh-table tr:hover td { background: var(--canvas-subtle); }

/* =========================================================================
   Page header (sub-pages)
   ========================================================================= */
.page-header { padding: 32px 0 28px; }
.page-header h1 {
  font-size: 28px;
  font-weight: 600;
  color: var(--fg-default);
  margin-bottom: 8px;
  letter-spacing: -0.3px;
}
.page-header p { color: var(--fg-muted); font-size: 14px; }

/* =========================================================================
   Content / article (daily + project detail)
   ========================================================================= */
.content-card {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  padding: 36px 44px;
  margin-bottom: 44px;
  max-width: 860px;
  margin-left: auto;
  margin-right: auto;
}
.content-card h1 {
  font-size: 26px;
  font-weight: 600;
  color: var(--fg-default);
  margin-bottom: 8px;
  letter-spacing: -0.3px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-default);
}
.content-card h2 {
  font-size: 19px;
  font-weight: 600;
  color: var(--fg-default);
  margin: 28px 0 12px;
  padding-bottom: 7px;
  border-bottom: 1px solid var(--border-default);
}
.content-card h3 {
  font-size: 15px;
  font-weight: 600;
  color: var(--fg-default);
  margin: 22px 0 8px;
}
.content-card p { font-size: 14px; margin-bottom: 12px; line-height: 1.7; color: var(--fg-default); }
.content-card strong { color: var(--fg-default); font-weight: 600; }
.content-card ul, .content-card ol { padding-left: 26px; margin: 10px 0 16px; }
.content-card li { margin: 5px 0; font-size: 14px; line-height: 1.65; }
.content-card code {
  font-family: var(--font-mono);
  font-size: 85%;
  background: var(--canvas-inset);
  padding: 0.2em 0.4em;
  border-radius: var(--radius-xs);
}
.content-card pre {
  font-family: var(--font-mono);
  background: var(--canvas-subtle);
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  overflow-x: auto;
  margin: 14px 0;
  font-size: 13px;
  line-height: 1.5;
  border: 1px solid var(--border-muted);
}
.content-card pre code { background: none; padding: 0; }
.content-card blockquote {
  background: var(--canvas-subtle);
  border-left: 4px solid var(--accent-fg);
  padding: 12px 16px;
  margin: 14px 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--fg-default);
}
.content-card blockquote p:last-child { margin-bottom: 0; }
.content-card table {
  border-collapse: collapse;
  width: 100%;
  margin: 14px 0;
  display: block;
  overflow-x: auto;
}
.content-card th, .content-card td {
  border: 1px solid var(--border-default);
  padding: 8px 12px;
  text-align: left;
  font-size: 13px;
}
.content-card th {
  background: var(--canvas-subtle);
  font-weight: 600;
}
.content-card tr:nth-child(even) td { background: var(--canvas-subtle); }
.content-card a { color: var(--accent-fg); }
.content-card hr { border: none; border-top: 1px solid var(--border-default); margin: 24px 0; }

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent-fg);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 20px;
}
.back-link:hover { text-decoration: underline; }

/* =========================================================================
   Date sections (trends page)
   ========================================================================= */
.date-section {
  background: var(--canvas-default);
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 14px;
}
.date-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  transition: background 0.1s;
}
.date-toggle { cursor: pointer; }
.date-toggle:hover .date-header { background: var(--canvas-subtle); }
.date-badge {
  background: var(--canvas-subtle);
  color: var(--fg-default);
  border: 1px solid var(--border-default);
  padding: 3px 12px;
  border-radius: 2em;
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
  font-family: var(--font-mono);
}
.date-summary {
  flex: 1;
  font-size: 14px;
  color: var(--fg-muted);
  font-weight: 400;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.date-arrow { color: var(--fg-muted); font-size: 12px; }
.date-trends { padding: 0 18px 14px; }

/* =========================================================================
   Footer
   ========================================================================= */
.footer {
  text-align: center;
  padding: 28px 0;
  border-top: 1px solid var(--border-default);
  color: var(--fg-muted);
  font-size: 12px;
}
.footer a { color: var(--accent-fg); text-decoration: none; }
.footer a:hover { text-decoration: underline; }

/* =========================================================================
   Mermaid diagrams
   ========================================================================= */
.content-card .mermaid {
  background: var(--canvas-subtle);
  border: 1px solid var(--border-default);
  border-left: 3px solid var(--accent-fg);
  border-radius: var(--radius-sm);
  padding: 20px 16px;
  overflow-x: auto;
  text-align: center;
  margin: 16px 0 24px;
}
.content-card .mermaid svg { max-width: 100%; height: auto; }

/* =========================================================================
   Responsive
   ========================================================================= */
@media (max-width: 768px) {
  .hero-title { font-size: 28px; }
  .stats-row { grid-template-columns: repeat(2, 1fr); }
  .nav-links span { display: none; }
  .nav-links a { padding: 8px 10px; }
  .brief-card, .content-card { padding: 22px 18px; }
  .container { padding: 24px 16px 48px; }
}
@media (max-width: 480px) {
  .card-grid { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; width: 100%; }
  .hero-actions .btn-primary, .hero-actions .btn-secondary { width: 100%; justify-content: center; }
}

/* =========================================================================
   Subtle fade-in on first paint (kept light — GitHub is restrained)
   ========================================================================= */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
.hero, .stats-row, .brief-card { animation: fadeInUp 0.3s ease-out; }

/* Respect reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}