/* =============================================
   GitHubBook - 主样式表
   设计理念：科技感、深色主题、流量为王
   ============================================= */

:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: #21262d;
  --border-color: #30363d;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;
  --accent-green: #3fb950;
  --accent-blue: #58a6ff;
  --accent-orange: #f78166;
  --accent-yellow: #e3b341;
  --accent-purple: #bc8cff;
  --gradient-hero: linear-gradient(135deg, #0d1117 0%, #1a1f2e 50%, #0d1117 100%);
  --gradient-card: linear-gradient(145deg, #21262d, #161b22);
  --shadow-card: 0 4px 20px rgba(0,0,0,0.4);
  --radius-card: 12px;
  --radius-btn: 8px;
  --transition: 0.25s ease;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

/* ---- 滚动条 ---- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 3px; }

/* ===================== HEADER ===================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  padding: 0 24px;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-primary);
}

.logo-icon {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}

.logo-text span {
  color: var(--accent-blue);
}

.main-nav {
  display: flex;
  gap: 4px;
  align-items: center;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  padding: 6px 14px;
  border-radius: var(--radius-btn);
  font-size: 0.9rem;
  font-weight: 500;
  transition: var(--transition);
}

.nav-link:hover {
  color: var(--text-primary);
  background: var(--bg-card);
}

.nav-link.active {
  color: var(--accent-blue);
  background: rgba(88, 166, 255, 0.1);
}

.nav-badge {
  background: var(--accent-orange);
  color: #fff;
  font-size: 0.65rem;
  padding: 1px 5px;
  border-radius: 10px;
  margin-left: 4px;
  vertical-align: middle;
  font-weight: 700;
}

.header-cta {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn-github {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 6px 14px;
  border-radius: var(--radius-btn);
  font-size: 0.85rem;
  cursor: pointer;
  text-decoration: none;
  transition: var(--transition);
}

.btn-github:hover {
  background: var(--border-color);
}

/* ===================== HERO ===================== */
.hero {
  background: var(--gradient-hero);
  padding: 80px 24px 60px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(ellipse at center, rgba(88, 166, 255, 0.06) 0%, transparent 60%);
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(63, 185, 80, 0.1);
  border: 1px solid rgba(63, 185, 80, 0.3);
  color: var(--accent-green);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 20px;
  letter-spacing: 0.5px;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent-blue) 50%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 32px;
}

.hero-btns {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent-blue);
  color: #0d1117;
  padding: 10px 22px;
  border-radius: var(--radius-btn);
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  transition: var(--transition);
}

.btn-primary:hover {
  background: #79c0ff;
  transform: translateY(-1px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: var(--text-primary);
  padding: 10px 22px;
  border-radius: var(--radius-btn);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.btn-secondary:hover {
  background: var(--bg-card);
  border-color: var(--accent-blue);
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 40px;
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
}

.stat-item {
  text-align: center;
}

.stat-num {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent-blue);
  display: block;
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 2px;
}

/* ===================== MAIN LAYOUT ===================== */
.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px;
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 32px;
}

.content-area { min-width: 0; }

/* ===================== SECTION HEADERS ===================== */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.section-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.15rem;
  font-weight: 700;
}

.section-icon {
  font-size: 1.1rem;
}

.section-link {
  color: var(--accent-blue);
  text-decoration: none;
  font-size: 0.85rem;
  transition: var(--transition);
}

.section-link:hover { text-decoration: underline; }

/* ===================== TREND CARDS ===================== */
.trend-list { display: flex; flex-direction: column; gap: 16px; margin-bottom: 40px; }

.trend-card {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 20px;
  transition: var(--transition);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.trend-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 20px rgba(88, 166, 255, 0.12);
  transform: translateY(-2px);
}

.trend-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: linear-gradient(180deg, var(--accent-blue), var(--accent-purple));
  opacity: 0;
  transition: var(--transition);
}

.trend-card:hover::before { opacity: 1; }

.card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}

.card-rank {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-muted);
  background: var(--bg-primary);
  padding: 2px 8px;
  border-radius: 20px;
  white-space: nowrap;
  flex-shrink: 0;
}

.card-rank.top3 { color: var(--accent-yellow); }

.card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--accent-blue);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 6px;
  flex: 1;
}

.card-title:hover { color: #79c0ff; }

.card-desc {
  color: var(--text-secondary);
  font-size: 0.88rem;
  margin-bottom: 12px;
  line-height: 1.5;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.meta-tag {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.lang-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}

.stars-today {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.8rem;
  color: var(--accent-green);
  font-weight: 600;
  background: rgba(63, 185, 80, 0.1);
  padding: 2px 8px;
  border-radius: 12px;
}

/* ===================== BLOG POST CARDS ===================== */
.post-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 40px;
}

.post-card {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  overflow: hidden;
  transition: var(--transition);
  text-decoration: none;
  color: inherit;
  display: block;
}

.post-card:hover {
  border-color: var(--accent-blue);
  transform: translateY(-2px);
  box-shadow: var(--shadow-card);
}

.post-card-img {
  height: 120px;
  background: linear-gradient(135deg, #1a1f2e, #2a3245);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  position: relative;
  overflow: hidden;
}

.post-card-img::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, transparent 50%, rgba(13,17,23,0.8));
}

.post-card-body { padding: 14px; }

.post-tag {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 12px;
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.tag-hot { background: rgba(247,129,102,0.15); color: var(--accent-orange); }
.tag-ai { background: rgba(188,140,255,0.15); color: var(--accent-purple); }
.tag-dev { background: rgba(88,166,255,0.15); color: var(--accent-blue); }
.tag-weekly { background: rgba(227,179,65,0.15); color: var(--accent-yellow); }

.post-card h3 {
  font-size: 0.9rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.post-card-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ===================== SIDEBAR ===================== */
.sidebar { display: flex; flex-direction: column; gap: 24px; }

.sidebar-card {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 20px;
}

.sidebar-card h3 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-primary);
}

/* 热门语言 */
.lang-list { display: flex; flex-direction: column; gap: 10px; }

.lang-item {
  display: flex;
  align-items: center;
  gap: 10px;
}

.lang-bar-wrap {
  flex: 1;
  background: var(--bg-primary);
  border-radius: 4px;
  height: 6px;
  overflow: hidden;
}

.lang-bar {
  height: 100%;
  border-radius: 4px;
  transition: width 1s ease;
}

.lang-name { font-size: 0.82rem; color: var(--text-secondary); width: 80px; }
.lang-pct { font-size: 0.78rem; color: var(--text-muted); width: 36px; text-align: right; }

/* 热门标签 */
.tag-cloud { display: flex; flex-wrap: wrap; gap: 8px; }

.tag-item {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 0.78rem;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.tag-item:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  background: rgba(88, 166, 255, 0.06);
}

/* 订阅卡片 */
.subscribe-card {
  background: linear-gradient(135deg, rgba(88,166,255,0.1), rgba(188,140,255,0.1));
  border: 1px solid rgba(88,166,255,0.2);
}

.subscribe-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.subscribe-form {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.subscribe-input {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 8px 12px;
  border-radius: var(--radius-btn);
  font-size: 0.85rem;
  outline: none;
  transition: var(--transition);
}

.subscribe-input:focus { border-color: var(--accent-blue); }

.subscribe-btn {
  background: var(--accent-blue);
  color: #0d1117;
  padding: 8px 16px;
  border-radius: var(--radius-btn);
  font-weight: 700;
  font-size: 0.85rem;
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.subscribe-btn:hover { background: #79c0ff; }

/* ===================== TICKER ===================== */
.ticker-bar {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  padding: 8px 0;
  overflow: hidden;
}

.ticker-inner {
  display: flex;
  gap: 0;
  animation: ticker 40s linear infinite;
  white-space: nowrap;
}

.ticker-item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0 24px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  border-right: 1px solid var(--border-color);
}

.ticker-item .up { color: var(--accent-green); font-weight: 600; }

@keyframes ticker {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

/* ===================== FOOTER ===================== */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 40px 24px 20px;
  margin-top: 60px;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}

.footer-brand p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 10px;
  max-width: 260px;
  line-height: 1.7;
}

.footer-col h4 {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
  letter-spacing: 0.5px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-col a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.82rem;
  transition: var(--transition);
}

.footer-col a:hover { color: var(--accent-blue); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 20px;
  border-top: 1px solid var(--border-color);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-links { display: flex; gap: 16px; }

/* ===================== PAGE SPECIFIC ===================== */
/* 全宽布局（用于帖子列表页等） */
.full-width {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px;
}

/* 帖子详情页 */
.post-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 40px 24px;
}

.post-hero {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 32px;
  margin-bottom: 32px;
  position: relative;
  overflow: hidden;
}

.post-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple), var(--accent-orange));
}

.post-hero h1 {
  font-size: 1.8rem;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 14px;
}

.post-meta-bar {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.post-content {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 32px;
}

.post-content h2 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent-blue);
  margin: 28px 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 8px;
}

.post-content p {
  color: var(--text-secondary);
  margin-bottom: 14px;
  font-size: 0.95rem;
  line-height: 1.8;
}

.post-content a {
  color: var(--accent-blue);
  text-decoration: none;
}

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

/* 项目卡片（博文内用） */
.project-card {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 20px;
  margin-bottom: 16px;
  transition: var(--transition);
}

.project-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 16px rgba(88,166,255,0.1);
}

.project-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--accent-blue);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 8px;
}

.project-desc {
  color: var(--text-secondary);
  font-size: 0.88rem;
  margin-bottom: 12px;
  line-height: 1.6;
}

.project-stats {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.project-stat {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.rank-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  font-size: 0.75rem;
  font-weight: 800;
  flex-shrink: 0;
  float: right;
  margin-left: 12px;
}

.rank-1 { background: linear-gradient(135deg, #ffd700, #ff9500); color: #000; }
.rank-2 { background: linear-gradient(135deg, #c0c0c0, #a0a0a0); color: #000; }
.rank-3 { background: linear-gradient(135deg, #cd7f32, #a0522d); color: #fff; }
.rank-other { background: var(--bg-card); color: var(--text-muted); }

/* 分析块 */
.insight-box {
  background: rgba(88, 166, 255, 0.06);
  border: 1px solid rgba(88, 166, 255, 0.2);
  border-radius: var(--radius-card);
  padding: 20px;
  margin: 20px 0;
}

.insight-box h3 {
  color: var(--accent-blue);
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.insight-box ul {
  list-style: none;
  padding: 0;
}

.insight-box li {
  color: var(--text-secondary);
  font-size: 0.88rem;
  padding: 4px 0;
  padding-left: 16px;
  position: relative;
  line-height: 1.7;
}

.insight-box li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--accent-blue);
}

/* ===================== AI学堂 ===================== */
.coming-soon {
  text-align: center;
  padding: 80px 24px;
}

.coming-soon .cs-icon { font-size: 4rem; margin-bottom: 20px; }

.coming-soon h2 {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 12px;
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.coming-soon p {
  color: var(--text-secondary);
  max-width: 500px;
  margin: 0 auto 24px;
}

/* ===================== RESPONSIVE ===================== */
@media (max-width: 900px) {
  .main-content {
    grid-template-columns: 1fr;
  }
  .sidebar { display: none; }
  .hero h1 { font-size: 2rem; }
  .hero-stats { gap: 24px; }
  .post-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 24px; }
}

@media (max-width: 600px) {
  .main-nav { display: none; }
  .hero h1 { font-size: 1.6rem; }
  .hero-stats { flex-wrap: wrap; gap: 16px; }
  .footer-grid { grid-template-columns: 1fr; }
}

/* ===================== ANIMATIONS ===================== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.fade-in { animation: fadeInUp 0.5s ease forwards; }

.trend-card:nth-child(1) { animation-delay: 0.05s; }
.trend-card:nth-child(2) { animation-delay: 0.1s; }
.trend-card:nth-child(3) { animation-delay: 0.15s; }
.trend-card:nth-child(4) { animation-delay: 0.2s; }
.trend-card:nth-child(5) { animation-delay: 0.25s; }

/* ===================== UTILITY ===================== */
.text-green { color: var(--accent-green); }
.text-blue { color: var(--accent-blue); }
.text-orange { color: var(--accent-orange); }
.text-yellow { color: var(--accent-yellow); }
.text-purple { color: var(--accent-purple); }
.text-muted { color: var(--text-muted); }
.mt-0 { margin-top: 0; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }

/* 返回顶部按钮 */
.back-to-top {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 40px;
  height: 40px;
  background: var(--accent-blue);
  color: #0d1117;
  border: none;
  border-radius: 50%;
  font-size: 1.1rem;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  z-index: 99;
  box-shadow: 0 4px 12px rgba(88,166,255,0.4);
}

.back-to-top.visible { display: flex; }
.back-to-top:hover { background: #79c0ff; transform: translateY(-2px); }