@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Noto+Sans+TC:wght@300;400;500;700&display=swap');

:root {
  /* Tech Portal Light Theme Color Palette */
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  --bg-surface-hover: #f1f5f9;
  --bg-surface-glass: rgba(255, 255, 255, 0.85);
  --border-color: rgba(15, 23, 42, 0.08);
  --border-glow: rgba(16, 185, 129, 0.2);
  
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  
  --primary: #10b981; /* Emerald Green accent */
  --primary-hover: #059669;
  --primary-glow: rgba(16, 185, 129, 0.1);
  
  --secondary: #0ea5e9; /* Sky Blue accent */
  --secondary-glow: rgba(14, 165, 233, 0.1);
  
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;

  /* Typography */
  --font-sans: 'Inter', 'Noto Sans TC', sans-serif;
  
  /* Shared Layout */
  --max-width: 1200px;
  --article-width: 820px;
  
  /* Animations & Shadows */
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.05), 0 2px 4px -1px rgba(15, 23, 42, 0.02);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.06), 0 4px 6px -2px rgba(15, 23, 42, 0.03);
  --shadow-glow: 0 0 15px 0 rgba(16, 185, 129, 0.05);
}

/* Reset & Base Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-base);
  color: var(--text-secondary);
  line-height: 1.8;
  font-size: 16px;
  overflow-x: hidden;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Container */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header Navigation Bar */
header.site-header {
  position: sticky;
  top: 0;
  background: var(--bg-surface-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  z-index: 100;
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

header.site-header .nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.logo-link {
  display: flex;
  align-items: center;
  text-decoration: none;
  font-weight: 700;
  font-size: 18px;
  color: var(--text-primary);
  gap: 8px;
}

.logo-link span.brand {
  letter-spacing: 0.02em;
}

.logo-link .logo-icon {
  width: 28px;
  height: 28px;
  background: var(--text-primary);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 900;
  font-size: 12px;
}

.nav-menu {
  display: flex;
  gap: 32px;
  list-style: none;
  align-items: center;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 14.5px;
  transition: color var(--transition-fast);
}

.nav-link:hover {
  color: var(--primary);
}

.nav-cta {
  display: inline-block;
  background-color: var(--text-primary);
  color: #ffffff;
  padding: 8px 18px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-fast);
  border: 1px solid transparent;
}

.nav-cta:hover {
  background-color: var(--primary);
  color: #ffffff;
}

/* Page Hero Section */
.hero-header {
  padding: 60px 0 30px;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
  background-color: #ffffff;
}

.hero-meta {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 16px;
  font-size: 13.5px;
  color: var(--text-muted);
}

.hero-title {
  font-size: 2.2rem;
  line-height: 1.35;
  font-weight: 700;
  color: var(--text-primary);
  max-width: 900px;
  margin: 0 auto;
}

/* Main Grid Layout */
.layout-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
  padding: 30px 0 60px;
}

@media (min-width: 768px) {
  .layout-grid {
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 40px;
  }
}

/* Main Article Content */
article.article-body {
  max-width: var(--article-width);
  margin: 0 auto;
}

article.article-body h2 {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-top: 44px;
  margin-bottom: 20px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}

article.article-body h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-top: 28px;
  margin-bottom: 12px;
}

article.article-body p {
  margin-bottom: 24px;
  color: var(--text-secondary);
  text-align: justify;
}

article.article-body strong {
  color: var(--text-primary);
}

article.article-body ul, article.article-body ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

article.article-body li {
  margin-bottom: 8px;
  color: var(--text-secondary);
}

/* Custom Highlight Alerts */
.alert {
  padding: 20px 24px;
  border-radius: 10px;
  margin: 30px 0;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  position: relative;
  overflow: hidden;
}

.alert::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
}

.alert-note {
  border-color: rgba(14, 165, 233, 0.12);
  background: linear-gradient(135deg, var(--bg-surface) 0%, rgba(14, 165, 233, 0.02) 100%);
}
.alert-note::before { background-color: var(--info); }

.alert-tip {
  border-color: rgba(16, 185, 129, 0.12);
  background: linear-gradient(135deg, var(--bg-surface) 0%, rgba(16, 185, 129, 0.02) 100%);
}
.alert-tip::before { background-color: var(--primary); }

.alert-warning {
  border-color: rgba(245, 158, 11, 0.12);
  background: linear-gradient(135deg, var(--bg-surface) 0%, rgba(245, 158, 11, 0.02) 100%);
}
.alert-warning::before { background-color: var(--warning); }

.alert-title {
  font-weight: 700;
  font-size: 14.5px;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
  letter-spacing: 0.02em;
}

.alert-note .alert-title { color: var(--info); }
.alert-tip .alert-title { color: var(--primary); }
.alert-warning .alert-title { color: var(--warning); }

/* Blockquotes Styled as Alert Boxes */
blockquote {
  padding: 20px 24px;
  border-radius: 10px;
  margin: 30px 0;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--primary);
  border-color: rgba(16, 185, 129, 0.12);
  background: linear-gradient(135deg, var(--bg-surface) 0%, rgba(16, 185, 129, 0.02) 100%);
  font-style: normal;
  color: var(--text-secondary);
}

blockquote p {
  margin-bottom: 12px;
  line-height: 1.6;
}

blockquote p:last-child {
  margin-bottom: 0;
}

blockquote ul, blockquote ol {
  margin-bottom: 0;
  padding-left: 20px;
}

blockquote li {
  margin-bottom: 6px;
  font-size: 14px;
}

/* Code Blocks */
.code-block-container {
  margin: 30px 0;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.code-block-container pre {
  margin: 0;
  border-radius: 0;
}

.code-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background-color: #1e293b;
  padding: 8px 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  font-family: var(--font-sans);
  font-size: 12px;
  color: #94a3b8;
  font-weight: 600;
}

.copy-btn {
  background: transparent;
  border: 1px solid rgba(148, 163, 184, 0.3);
  color: #94a3b8;
  padding: 4px 10px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 11px;
  transition: all var(--transition-fast);
  font-family: var(--font-sans);
}

.copy-btn:hover {
  background-color: rgba(255, 255, 255, 0.08);
  color: #f8fafc;
  border-color: rgba(255, 255, 255, 0.2);
}

pre {
  background-color: #0f172a;
  color: #e2e8f0;
  border-radius: 10px;
  padding: 20px;
  margin: 30px 0;
  overflow-x: auto;
  font-family: 'Courier New', Courier, monospace;
  font-size: 13.5px;
}

code {
  font-family: 'Fira Code', 'Courier New', Courier, monospace;
  padding: 2px 6px;
  background-color: rgba(15, 23, 42, 0.04);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 0.9em;
  color: #f43f5e;
}

pre code {
  padding: 0;
  background-color: transparent;
  border: 0;
  border-radius: 0;
  color: inherit;
}

/* Tables */
.table-container {
  overflow-x: auto;
  margin: 30px 0;
  border-radius: 10px;
  border: 1px solid var(--border-color);
  background-color: #ffffff;
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 14.5px;
}

th, td {
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-color);
}

th {
  background-color: #f8fafc;
  color: var(--text-primary);
  font-weight: 600;
}

tr:last-child td {
  border-bottom: 0;
}

tr:hover td {
  background-color: var(--bg-surface-hover);
}

/* Sidebar Navigation (TOC) */
.sidebar {
  position: sticky;
  top: 100px;
  align-self: start;
}

.toc-container {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 20px;
}

.toc-title {
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-primary);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.toc-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.toc-item a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 13.5px;
  transition: all var(--transition-fast);
  display: block;
  line-height: 1.4;
}

.toc-item a:hover, .toc-item.active a {
  color: var(--primary);
  padding-left: 4px;
}

.toc-item.active {
  border-left: 2px solid var(--primary);
  padding-left: 8px;
  margin-left: -8px;
}

/* Custom Portal Call to Action */
.article-cta {
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.05) 0%, rgba(14, 165, 233, 0.05) 100%);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 28px;
  margin: 50px 0 20px;
  text-align: center;
}

.article-cta h4 {
  font-size: 1.35rem;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.article-cta p {
  color: var(--text-secondary);
  font-size: 14.5px;
  max-width: 640px;
  margin: 0 auto 20px;
}

.cta-button {
  display: inline-block;
  background-color: var(--text-primary);
  color: #ffffff;
  text-decoration: none;
  padding: 10px 24px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 14px;
  transition: all var(--transition-fast);
}

.cta-button:hover {
  background-color: var(--primary);
  box-shadow: 0 4px 10px rgba(16, 185, 129, 0.15);
  transform: translateY(-1px);
}

/* Home / Portal Specific Layout */
.home-hero {
  text-align: center;
  padding: 60px 24px;
  background-color: #ffffff;
  border-bottom: 1px solid var(--border-color);
}

.home-hero h1 {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.home-hero p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 720px;
  margin: 0 auto;
  line-height: 1.6;
}

.articles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  margin-top: 30px;
}

@media (min-width: 768px) {
  .articles-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.article-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
  text-decoration: none;
  height: 100%;
}

.article-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.card-tag {
  background-color: #f1f5f9;
  color: var(--text-secondary);
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  display: inline-block;
  margin-bottom: 12px;
  align-self: start;
}

.card-body {
  padding: 24px;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
}

.card-meta {
  font-size: 12.5px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.4;
  margin-bottom: 10px;
  transition: color var(--transition-fast);
}

.article-card:hover .card-title {
  color: var(--primary);
}

.card-excerpt {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.card-footer {
  display: flex;
  align-items: center;
  color: var(--primary);
  font-weight: 600;
  font-size: 13.5px;
  gap: 4px;
  margin-top: auto;
}

.card-footer svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
  transition: transform var(--transition-fast);
}

.article-card:hover .card-footer svg {
  transform: translateX(3px);
}

/* Footer Section */
footer.site-footer {
  background-color: #ffffff;
  border-top: 1px solid var(--border-color);
  padding: 40px 0;
  margin-top: 60px;
  text-align: center;
  color: var(--text-muted);
  font-size: 13.5px;
}

footer.site-footer .footer-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

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

.footer-nav a {
  text-decoration: none;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.footer-nav a:hover {
  color: var(--primary);
}

/* Mobile Navigation button */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }
  .nav-menu.active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background-color: var(--bg-surface);
    border-bottom: 1px solid var(--border-color);
    padding: 20px;
    gap: 16px;
  }
  .mobile-menu-btn {
    display: block;
  }
}