/* ========================================
   墨 Mo - 极简主义博客系统
   灵感来自中国传统水墨画
   ======================================== */

/* CSS Variables */
:root {
  /* Colors - Light Theme */
  --color-bg: #fafaf9;
  --color-bg-secondary: #f5f5f4;
  --color-text: #1c1917;
  --color-text-secondary: #57534e;
  --color-text-muted: #a8a29e;
  --color-accent: #292524;
  --color-border: #e7e5e4;
  --color-card: #ffffff;
  --color-shadow: rgba(0, 0, 0, 0.05);

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  --font-serif: 'Noto Serif SC', 'Songti SC', SimSun, serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Layout */
  --max-width: 680px;
  --header-height: 64px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
}

/* Dark Theme */
[data-theme="dark"] {
  --color-bg: #0c0a09;
  --color-bg-secondary: #1c1917;
  --color-text: #fafaf9;
  --color-text-secondary: #a8a29e;
  --color-text-muted: #78716c;
  --color-accent: #fafaf9;
  --color-border: #292524;
  --color-card: #1c1917;
  --color-shadow: rgba(0, 0, 0, 0.3);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  min-height: 100vh;
  transition: background-color var(--transition-base), color var(--transition-base);
}

/* App Container */
#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ========================================
   Header
   ======================================== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: blur(12px);
  background-color: rgba(250, 250, 249, 0.8);
}

[data-theme="dark"] .header {
  background-color: rgba(12, 10, 9, 0.8);
}

.header-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: baseline;
  gap: var(--space-xs);
  text-decoration: none;
  color: var(--color-text);
}

.logo-char {
  font-family: var(--font-serif);
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
}

.logo-en {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  font-weight: 300;
}

.nav {
  display: flex;
  gap: var(--space-lg);
}

.nav-link {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background-color: var(--color-text);
  transition: width var(--transition-base);
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-text);
}

.nav-link.active::after {
  width: 100%;
}

.theme-toggle {
  width: 36px;
  height: 36px;
  border: none;
  background: transparent;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

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

.theme-toggle .icon-moon,
.theme-toggle .icon-sun {
  width: 20px;
  height: 20px;
}

.theme-toggle .icon-moon {
  display: block;
}

.theme-toggle .icon-sun {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
  display: block;
}

/* ========================================
   Main Content
   ======================================== */
.main {
  flex: 1;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg);
  width: 100%;
}

.view {
  display: none;
  animation: fadeIn var(--transition-slow) ease;
}

.view.active {
  display: block;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
  text-align: center;
  padding: var(--space-3xl) 0;
  position: relative;
}

.hero-title {
  font-size: 4rem;
  font-weight: 200;
  letter-spacing: 0.3em;
  margin-bottom: var(--space-md);
  color: var(--color-text);
}

.hero-char {
  font-family: var(--font-serif);
}

.hero-subtitle {
  font-size: 1rem;
  color: var(--color-text-muted);
  letter-spacing: 0.2em;
  font-weight: 300;
}

.hero-decoration {
  width: 60px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-text-muted), transparent);
  margin: var(--space-xl) auto 0;
}

/* ========================================
   Post Cards
   ======================================== */
.posts-container {
  margin-top: var(--space-xl);
}

.posts-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.post-card {
  padding: var(--space-xl);
  background-color: var(--color-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.post-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--color-shadow);
  border-color: var(--color-text-muted);
}

.post-link {
  display: block;
  text-decoration: none;
  color: inherit;
}

.post-title-row {
  display: flex;
  align-items: baseline;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.post-title {
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--color-text);
  transition: color var(--transition-fast);
}

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

.post-excerpt {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin-top: var(--space-md);

  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.post-date {
  margin-right: 10px;
}

.post-category {
  padding: 2px 8px;
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  text-decoration: none;
  font-size: 0.8rem;
  transition: background-color var(--transition-fast), color var(--transition-fast);
  margin-left: 10px;
}

.post-category:hover {
  background-color: var(--color-accent);
  color: var(--color-bg);
}

.post-tag {
  padding: 2px 8px;
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.8rem;
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.post-tag:hover {
  color: var(--color-text);
  background-color: var(--color-border);
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}

.post-detail-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  justify-content: center;
  margin-top: var(--space-md);
}

/* ========================================
   Archive View
   ======================================== */
.archive-header {
  text-align: center;
  padding: var(--space-2xl) 0;
}

.archive-title {
  font-size: 2rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  margin-bottom: var(--space-sm);
}

.archive-count {
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.archive-list {
  display: flex;
  flex-direction: column;
}

.archive-year {
  margin-bottom: var(--space-xl);
}

.archive-year-title {
  font-size: 1.5rem;
  font-weight: 300;
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--color-border);
}

.archive-posts {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.archive-item {
  display: flex;
  align-items: center;
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: var(--color-text);
  transition: background-color var(--transition-fast);
}

.archive-item:hover {
  background-color: var(--color-bg-secondary);
}

.archive-item-date {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  width: 60px;
  flex-shrink: 0;
}

.archive-item-title {
  font-size: 0.95rem;
}

/* ========================================
   About View
   ======================================== */
.about-content {
  text-align: center;
  padding: var(--space-2xl) 0;
}

.about-avatar {
  margin-bottom: var(--space-xl);
}

.avatar-placeholder {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-bg-secondary) 0%, var(--color-border) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto;
  font-family: var(--font-serif);
  font-size: 2.5rem;
  color: var(--color-text-muted);
}

.about-title {
  font-size: 1.5rem;
  font-weight: 400;
  letter-spacing: 0.2em;
  margin-bottom: var(--space-xl);
}

.about-text {
  max-width: 400px;
  margin: 0 auto var(--space-xl);
  color: var(--color-text-secondary);
  line-height: 2;
}

.about-text p {
  margin-bottom: var(--space-sm);
}

.about-meta {
  display: flex;
  justify-content: center;
  gap: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border);
}

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

.meta-label {
  display: block;
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
}

.meta-value {
  font-size: 1.5rem;
  font-weight: 300;
}

/* ========================================
   Post Detail View
   ======================================== */
.post-detail {
  max-width: 100%;
}

.post-detail-header {
  margin-bottom: var(--space-2xl);
  text-align: center;
}

.post-detail-title {
  font-size: 2rem;
  font-weight: 500;
  line-height: 1.4;
  margin-bottom: var(--space-md);
}

.post-detail-meta {
  display: flex;
  justify-content: center;
  gap: var(--space-md);
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

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

.post-detail-content h1,
.post-detail-content h2,
.post-detail-content h3 {
  font-weight: 500;
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-md);
}

.post-detail-content h1 { font-size: 1.75rem; }
.post-detail-content h2 { font-size: 1.5rem; }
.post-detail-content h3 { font-size: 1.25rem; }

.post-detail-content p {
  margin-bottom: var(--space-lg);
}

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

.post-detail-content a:hover {
  text-decoration-color: var(--color-text);
}

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

.post-detail-content pre {
  background-color: var(--color-bg-secondary);
  padding: var(--space-lg);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin-bottom: var(--space-lg);
}

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

.post-detail-content blockquote {
  border-left: 3px solid var(--color-border);
  padding-left: var(--space-lg);
  margin: var(--space-lg) 0;
  color: var(--color-text-secondary);
  font-style: italic;
}

.post-detail-content ul,
.post-detail-content ol {
  margin-bottom: var(--space-lg);
  padding-left: var(--space-xl);
}

.post-detail-content li {
  margin-bottom: var(--space-sm);
}

.post-detail-content img {
  max-width: 100%;
  border-radius: var(--radius-md);
  margin: var(--space-lg) 0;
}

.post-detail-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-top: var(--space-xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
}

.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-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  text-decoration: none;
  color: inherit;
  flex: 1;
  max-width: 50%;
}

.post-nav-prev {
  align-items: flex-start;
}

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

.post-nav-label {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.post-nav-title {
  font-size: 0.9rem;
  color: var(--color-text);
  transition: color var(--transition-fast);
  line-height: 1.4;
}

.post-nav-item {
  transition: transform var(--transition-fast);
}

.post-nav-item:hover {
  transform: translateX(-4px);
}

.post-nav-next:hover {
  transform: translateX(4px);
}

.post-nav-item:hover .post-nav-title {
  color: var(--color-accent);
}

.post-back {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

.post-back:hover {
  color: var(--color-text);
}

.post-back svg {
  width: 16px;
  height: 16px;
}

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

.footer-text {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  letter-spacing: 0.1em;
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 640px) {
  .hero-title {
    font-size: 3rem;
  }

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

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

  .post-link {
    padding: var(--space-lg);
  }

  .post-title {
    font-size: 1.1rem;
  }

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

  .about-meta {
    gap: var(--space-xl);
  }
}

/* ========================================
   Scrollbar
   ======================================== */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-muted);
}

/* ========================================
   Selection
   ======================================== */
::selection {
  background-color: var(--color-text);
  color: var(--color-bg);
}

/* ========================================
   Load More Button
   ======================================== */
.load-more {
  text-align: center;
  padding: var(--space-2xl) 0;
}

.load-more-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md) var(--space-xl);
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  min-width: 160px;
}

.load-more-btn:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px var(--color-shadow);
}

.load-more-btn.loading {
  opacity: 0.7;
  cursor: not-allowed;
}

.load-more-btn.loading .load-more-text::after {
  content: '';
  display: inline-block;
  width: 12px;
  height: 12px;
  margin-left: var(--space-sm);
  border: 2px solid var(--color-border);
  border-top-color: var(--color-text);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ========================================
   404 Page
   ======================================== */
.not-found {
  text-align: center;
  padding: 80px 0 120px;
}
.nf-code {
  font-size: 6rem;
  font-weight: 200;
  color: var(--color-text-muted);
  letter-spacing: 0.1em;
  line-height: 1;
  margin-bottom: var(--space-lg);
}
.nf-text {
  font-size: 1.5rem;
  font-weight: 400;
  margin-bottom: var(--space-sm);
}
.nf-desc {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  margin-bottom: var(--space-2xl);
}
.nf-btn {
  display: inline-block;
  padding: var(--space-sm) var(--space-xl);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  text-decoration: none;
  font-size: 0.9rem;
  transition: all var(--transition-base);
}
.nf-btn:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}

/* 隐藏式加载（滚动触发时隐藏按钮） */
.load-more.hide-btn {
  display: none;
}

/* ─── 分页 ─── */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 32px 0 48px;
}
.page-btn, .page-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  padding: 0 12px;
  border-radius: 8px;
  font-size: 14px;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: all 0.2s;
  border: 1px solid transparent;
}
.page-btn:hover, .page-num:hover {
  color: var(--color-text);
  background: var(--color-bg-secondary);
}
.page-num.active {
  color: var(--color-bg);
  background: var(--color-accent);
  font-weight: 500;
}
.page-btn {
  font-size: 14px;
}
.page-ellipsis {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  color: var(--color-text-secondary);
  user-select: none;
}

/* ========================================
   Category & Tag Pages
   ======================================== */
.tax-header {
  text-align: center;
  padding: var(--space-2xl) 0;
}

.tax-title {
  font-size: 2rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  margin-bottom: var(--space-sm);
}

.tax-count {
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.tax-back {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: 0.85rem;
  margin-bottom: var(--space-md);
  transition: color var(--transition-fast);
}

.tax-back:hover {
  color: var(--color-text);
}

.tax-back svg {
  width: 14px;
  height: 14px;
}

/* Category List */
.tax-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.tax-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  text-decoration: none;
  color: var(--color-text);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  transition: all var(--transition-base);
}

.tax-item:hover {
  background-color: var(--color-bg-secondary);
  border-color: var(--color-text-muted);
  transform: translateX(4px);
}

.tax-item-name {
  font-size: 1.05rem;
  font-weight: 400;
}

.tax-item-count {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  background-color: var(--color-bg-secondary);
  padding: 2px 10px;
  border-radius: 12px;
  min-width: 36px;
  text-align: center;
}

/* Tag Cloud */
.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  justify-content: center;
  padding: var(--space-xl) 0;
}

.tag-item {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-lg);
  text-decoration: none;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: 20px;
  font-size: 0.9rem;
  transition: all var(--transition-base);
}

.tag-item:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
  background-color: var(--color-bg-secondary);
  transform: translateY(-2px);
}

.tag-name {
  font-weight: 400;
}

.tag-count {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  background-color: var(--color-bg-secondary);
  padding: 1px 6px;
  border-radius: 8px;
}