/* ==========================================
   ZenMind Theme Styles
   A clean, minimalist Hexo theme
   ========================================== */

/* CSS Variables / Custom Properties */
:root {
  --bg-color: #ffffff;
  --text-color: #333333;
  --text-secondary: #666666;
  --link-color: #2c3e50;
  --link-hover: #3498db;
  --border-color: #e8e8e8;
  --card-bg: #ffffff;
  --code-bg: #f5f5f5;
  --tag-bg: #f0f0f0;
  --footer-bg: #fafafa;
  --max-width: 800px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Fira Mono", "Roboto Mono", monospace;
}

/* Dark Mode */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #1a1a1a;
    --text-color: #e0e0e0;
    --text-secondary: #999999;
    --link-color: #e0e0e0;
    --link-hover: #64b5f6;
    --border-color: #333333;
    --card-bg: #222222;
    --code-bg: #2d2d2d;
    --tag-bg: #333333;
    --footer-bg: #1e1e1e;
  }
}

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

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

/* Container */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ==========================================
   Header
   ========================================== */
.header {
  border-bottom: 1px solid var(--border-color);
  padding: 20px 0;
  background: var(--bg-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo a {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: 24px;
}

.nav-item a {
  font-size: 0.95rem;
  color: var(--text-secondary);
  padding: 4px 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s;
}

.nav-item a:hover {
  color: var(--link-hover);
  border-bottom-color: var(--link-hover);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-color);
}

/* ==========================================
   Main Content
   ========================================== */
.main {
  min-height: calc(100vh - 200px);
  padding: 40px 0;
}

/* ==========================================
   Post Card (Homepage)
   ========================================== */
.post-card {
  margin-bottom: 48px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--border-color);
}

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

.post-card-title {
  font-size: 1.6rem;
  font-weight: 600;
  margin-bottom: 8px;
  line-height: 1.3;
}

.post-card-title a {
  color: var(--text-color);
}

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

.post-card-meta {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.post-card-meta span {
  margin-left: 12px;
}

.post-card-excerpt {
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 12px;
}

.read-more {
  font-size: 0.9rem;
  color: var(--link-hover);
  font-weight: 500;
}

/* ==========================================
   Post Single Page
   ========================================== */
.post-header {
  margin-bottom: 32px;
}

.post-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.3;
}

.post-meta {
  font-size: 0.875rem;
  color: var(--text-secondary);
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.post-meta a {
  color: var(--text-secondary);
}

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

.post-content {
  font-size: 1.05rem;
  line-height: 1.9;
}

.post-content h1,
.post-content h2,
.post-content h3,
.post-content h4,
.post-content h5,
.post-content h6 {
  margin: 28px 0 16px;
  font-weight: 600;
  line-height: 1.3;
}

.post-content h1 { font-size: 1.8rem; }
.post-content h2 { font-size: 1.5rem; }
.post-content h3 { font-size: 1.3rem; }

.post-content p {
  margin-bottom: 16px;
}

.post-content img {
  max-width: 100%;
  height: auto;
  border-radius: 4px;
  margin: 16px 0;
}

.post-content blockquote {
  border-left: 4px solid var(--link-hover);
  padding: 12px 20px;
  margin: 16px 0;
  background: var(--code-bg);
  border-radius: 0 4px 4px 0;
}

.post-content blockquote p {
  margin-bottom: 0;
}

.post-content code {
  font-family: var(--font-mono);
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 0.9em;
}

.post-content pre {
  background: var(--code-bg);
  padding: 16px 20px;
  border-radius: 4px;
  overflow-x: auto;
  margin: 16px 0;
}

.post-content pre code {
  background: none;
  padding: 0;
  font-size: 0.9rem;
}

.post-content ul,
.post-content ol {
  padding-left: 24px;
  margin-bottom: 16px;
}

.post-content li {
  margin-bottom: 4px;
}

.post-content a {
  color: var(--link-hover);
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* Post Navigation */
.post-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.post-nav-prev,
.post-nav-next {
  flex: 1;
}

.post-nav-next {
  text-align: right;
}

.post-nav span {
  display: block;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.post-nav a {
  font-weight: 500;
}

/* ==========================================
   Archive
   ========================================== */
.archive-title {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 32px;
}

.archive-year {
  font-size: 1.3rem;
  font-weight: 600;
  margin: 24px 0 12px;
  color: var(--text-secondary);
}

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

.archive-item {
  padding: 8px 0;
  display: flex;
  align-items: baseline;
  gap: 16px;
  border-bottom: 1px solid var(--border-color);
}

.archive-item time {
  font-size: 0.85rem;
  color: var(--text-secondary);
  min-width: 60px;
  font-family: var(--font-mono);
}

/* ==========================================
   Pagination
   ========================================== */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.pagination a {
  padding: 6px 16px;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 0.9rem;
  transition: all 0.2s;
}

.pagination a:hover {
  background: var(--link-hover);
  color: white;
  border-color: var(--link-hover);
}

.page-info {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* ==========================================
   Page
   ========================================== */
.page-header {
  margin-bottom: 24px;
}

.page-title {
  font-size: 1.8rem;
  font-weight: 700;
}

.page-content {
  font-size: 1.05rem;
  line-height: 1.9;
}

/* ==========================================
   Footer
   ========================================== */
.footer {
  background: var(--footer-bg);
  border-top: 1px solid var(--border-color);
  padding: 24px 0;
  text-align: center;
}

.footer-inner {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.footer-inner a {
  color: var(--text-secondary);
}

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

.copyright {
  margin-bottom: 4px;
}

/* Back to Top */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--link-hover);
  color: white;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.3s;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

/* ==========================================
   Responsive
   ========================================== */
@media (max-width: 768px) {
  .header {
    padding: 16px 0;
  }

  .nav-list {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 20px;
    gap: 12px;
  }

  .nav-list.active {
    display: flex;
  }

  .menu-toggle {
    display: block;
  }

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

  .post-card-title {
    font-size: 1.3rem;
  }

  .post-nav {
    flex-direction: column;
    gap: 16px;
  }

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

  .archive-item {
    flex-direction: column;
    gap: 4px;
  }
}