/*
Theme Name: BrandVista Insights
Theme URI: https://insights.brandvista.com
Author: BrandVista Team
Author URI: https://www.brandvista.com
Description: A modern, feature-rich theme for BrandVista Insights blog with dark/light mode, featured images, and advanced filtering.
Version: 1.0.2
License: GNU General Public License v2 or later
License URI: http://www.gnu.org/licenses/gpl-2.0.html
Text Domain: brandvista-insights
Tags: blog, two-columns, custom-colors, custom-logo, featured-images, theme-options, dark-mode
*/

/* ============================================
   CSS Variables - Color Scheme
   ============================================ */
:root {
  /* Light Mode Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-card: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --accent-primary: #2563eb;
  --accent-hover: #1d4ed8;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
  
  /* Typography - 使用系统字体，避免内网加载外部字体超时 */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', Roboto, sans-serif;
  --font-serif: Georgia, 'Songti SC', 'SimSun', serif;
  
  /* Spacing */
  --container-width: 1200px;
  --content-width: 720px;
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 350ms ease;
}

/* Dark Mode Colors */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-card: #1e293b;
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #64748b;
  --accent-primary: #3b82f6;
  --accent-hover: #60a5fa;
  --border-color: #334155;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.4);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.5);
}

/* ============================================
   Base Styles
   ============================================ */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  margin: 0;
  padding: 0;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ============================================
   Container & Layout
   ============================================ */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.content-wrapper {
  max-width: var(--content-width);
  margin: 0 auto;
}

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) 0;
  gap: var(--spacing-lg);
}

.site-branding {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

/* Logo + Insights 组合样式 */
.brand-logo-wrapper {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  text-decoration: none;
  transition: opacity var(--transition-fast);
}

.brand-logo-wrapper:hover {
  opacity: 0.9;
}

.brand-logo-wrapper .site-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0;
  color: var(--text-primary);
}

.brand-logo-wrapper .custom-logo-link {
  display: flex;
  align-items: center;
}

.brand-logo-wrapper .custom-logo {
  height: 40px;
  width: auto;
}

.site-logo-img {
  height: 40px;
  width: auto;
  display: block;
}

.site-logo {
  height: 40px;
  width: auto;
}

.site-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0;
}

.site-title a {
  color: var(--text-primary);
}

.site-description {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin: 0;
}

/* Navigation */
.main-navigation {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-menu a {
  color: var(--text-secondary);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-menu a:hover {
  color: var(--text-primary);
  background-color: var(--bg-secondary);
}

.nav-menu .current-menu-item a {
  color: var(--accent-primary);
}

/* Theme Toggle Button */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  background-color: var(--border-color);
  color: var(--text-primary);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
}

/* Search Toggle */
.search-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.search-toggle:hover {
  background-color: var(--border-color);
  color: var(--text-primary);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: var(--spacing-sm);
  background: none;
  border: none;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--text-primary);
  transition: all var(--transition-fast);
}

/* ============================================
   Search Modal
   ============================================ */
.search-modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 200;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
}

.search-modal.active {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 15vh;
}

.search-modal-content {
  width: 100%;
  max-width: 600px;
  background-color: var(--bg-primary);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
}

.search-form-modal {
  display: flex;
  gap: var(--spacing-md);
}

.search-form-modal input[type="search"] {
  flex: 1;
  padding: var(--spacing-md) var(--spacing-lg);
  border: 2px solid var(--border-color);
  border-radius: var(--radius-lg);
  font-size: 1.125rem;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  transition: border-color var(--transition-fast);
}

.search-form-modal input[type="search"]:focus {
  outline: none;
  border-color: var(--accent-primary);
}

.search-form-modal button {
  padding: var(--spacing-md) var(--spacing-xl);
  background-color: var(--accent-primary);
  color: white;
  border: none;
  border-radius: var(--radius-lg);
  font-weight: 600;
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.search-form-modal button:hover {
  background-color: var(--accent-hover);
}

.search-close {
  position: absolute;
  top: var(--spacing-lg);
  right: var(--spacing-lg);
  width: 40px;
  height: 40px;
  border: none;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.search-close:hover {
  background-color: var(--border-color);
  color: var(--text-primary);
}

/* ============================================
   Hero Section
   ============================================ */
.hero-section {
  padding: var(--spacing-2xl) 0;
  text-align: center;
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.hero-title {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--accent-primary) 0%, #8b5cf6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-description {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================
   Filter Bar
   ============================================ */
.filter-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-md);
  padding: var(--spacing-lg) 0;
  flex-wrap: wrap;
}

.filter-btn {
  padding: var(--spacing-sm) var(--spacing-lg);
  border: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  color: var(--text-secondary);
  border-radius: var(--radius-lg);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-btn:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

.filter-btn.active {
  background-color: var(--accent-primary);
  border-color: var(--accent-primary);
  color: white;
}

/* ============================================
   Posts Grid
   ============================================ */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: var(--spacing-xl);
  padding: var(--spacing-2xl) 0;
}

/* Featured Post (Large) */
.post-card.featured {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xl);
}

.post-card.featured .post-thumbnail {
  height: 400px;
}

/* Regular Post Card */
.post-card {
  background-color: var(--bg-card);
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 1px solid var(--border-color);
  transition: all var(--transition-normal);
}

.post-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.post-thumbnail {
  position: relative;
  height: 220px;
  overflow: hidden;
}

.post-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.post-card:hover .post-thumbnail img {
  transform: scale(1.05);
}

.post-thumbnail-placeholder {
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--border-color) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
}

.post-category {
  position: absolute;
  top: var(--spacing-md);
  left: var(--spacing-md);
  padding: var(--spacing-xs) var(--spacing-md);
  background-color: var(--accent-primary);
  color: white;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.post-content {
  padding: var(--spacing-lg);
}

.post-meta {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
  font-size: 0.875rem;
  color: var(--text-muted);
}

.post-author a {
  color: var(--text-secondary);
  font-weight: 500;
}

.post-author a:hover {
  color: var(--accent-primary);
}

.post-title {
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: var(--spacing-sm);
}

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

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

.post-excerpt {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: var(--spacing-md);
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.post-tag {
  padding: var(--spacing-xs) var(--spacing-sm);
  background-color: var(--bg-secondary);
  color: var(--text-muted);
  font-size: 0.75rem;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

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

/* ============================================
   Single Post
   ============================================ */
.single-post-header {
  padding: var(--spacing-2xl) 0;
  text-align: center;
}

.single-post-title {
  font-size: 2.5rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: var(--spacing-lg);
}

.single-post-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-lg);
  color: var(--text-muted);
}

.single-post-author {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.author-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
}

.author-info {
  text-align: left;
}

.author-name {
  font-weight: 600;
  color: var(--text-primary);
}

.author-title {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.single-post-featured-image {
  margin: var(--spacing-2xl) 0;
  border-radius: var(--radius-xl);
  overflow: hidden;
}

.single-post-featured-image img {
  width: 100%;
  height: auto;
}

/* Post Content */
.post-content-body {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.8;
}

.post-content-body h2,
.post-content-body h3,
.post-content-body h4 {
  font-family: var(--font-sans);
  margin-top: var(--spacing-2xl);
  margin-bottom: var(--spacing-md);
}

.post-content-body p {
  margin-bottom: var(--spacing-lg);
}

.post-content-body blockquote {
  border-left: 4px solid var(--accent-primary);
  padding-left: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
  font-style: italic;
  color: var(--text-secondary);
}

.post-content-body code {
  padding: var(--spacing-xs) var(--spacing-sm);
  background-color: var(--bg-secondary);
  border-radius: var(--radius-sm);
  font-size: 0.875em;
}

.post-content-body pre {
  padding: var(--spacing-lg);
  background-color: var(--bg-secondary);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: var(--spacing-xl) 0;
}

.post-content-body img {
  border-radius: var(--radius-md);
  margin: var(--spacing-xl) 0;
}

/* ============================================
   Author Box
   ============================================ */
.author-box {
  display: flex;
  gap: var(--spacing-lg);
  padding: var(--spacing-xl);
  margin: var(--spacing-2xl) 0;
  background-color: var(--bg-secondary);
  border-radius: var(--radius-xl);
}

.author-box-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  object-fit: cover;
}

.author-box-content {
  flex: 1;
}

.author-box-name {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
}

.author-box-bio {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
}

.author-box-social {
  display: flex;
  gap: var(--spacing-md);
}

.author-box-social a {
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.author-box-social a:hover {
  color: var(--accent-primary);
}

/* ============================================
   Sidebar
   ============================================ */
.widget-area {
  padding: var(--spacing-xl);
  background-color: var(--bg-secondary);
  border-radius: var(--radius-xl);
}

.widget {
  margin-bottom: var(--spacing-xl);
}

.widget:last-child {
  margin-bottom: 0;
}

.widget-title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid var(--accent-primary);
}

.widget ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.widget li {
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--border-color);
}

.widget li:last-child {
  border-bottom: none;
}

/* ============================================
   Pagination
   ============================================ */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-2xl) 0;
}

.pagination a,
.pagination span {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  height: 44px;
  padding: 0 var(--spacing-md);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-weight: 500;
  transition: all var(--transition-fast);
}

.pagination a:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

.pagination .current {
  background-color: var(--accent-primary);
  border-color: var(--accent-primary);
  color: white;
}

/* ============================================
   Footer
   ============================================ */
.site-footer {
  margin-top: var(--spacing-2xl);
  padding: var(--spacing-2xl) 0;
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
}

.footer-inner {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-xl);
}

.footer-branding {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.footer-logo {
  height: 32px;
  width: auto;
}

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

.footer-nav h4 {
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--spacing-md);
}

.footer-nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-nav li {
  margin-bottom: var(--spacing-sm);
}

.footer-nav a {
  color: var(--text-muted);
  font-size: 0.875rem;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-xl);
  border-top: 1px solid var(--border-color);
  font-size: 0.875rem;
  color: var(--text-muted);
  text-align: center;
}

.icp-info {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.icp-info a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.icp-info a:hover {
  color: var(--accent-primary);
}

.icp-info .divider {
  margin: 0 var(--spacing-sm);
  color: var(--border-color);
}

.footer-social {
  display: flex;
  gap: var(--spacing-md);
}

.footer-social a {
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

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

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
  .post-card.featured {
    grid-template-columns: 1fr;
  }
  
  .post-card.featured .post-thumbnail {
    height: 300px;
  }
}

@media (max-width: 768px) {
  :root {
    --spacing-xl: 1.5rem;
    --spacing-2xl: 2rem;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .hero-description {
    font-size: 1rem;
  }
  
  .brand-suffix {
    font-size: 2rem;
  }
  
  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    padding: var(--spacing-lg);
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
  }
  
  .nav-menu.active {
    display: flex;
  }
  
  .menu-toggle {
    display: flex;
  }
  
  .posts-grid {
    grid-template-columns: 1fr;
  }
  
  .single-post-title {
    font-size: 1.75rem;
  }
  
  .author-box {
    flex-direction: column;
    text-align: center;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--spacing-md);
    text-align: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--spacing-md);
  }
  
  .hero-title {
    font-size: 1.75rem;
  }
  
  .brand-suffix {
    font-size: 1.5rem;
  }
  
  .post-title {
    font-size: 1.25rem;
  }
  
  .filter-bar {
    justify-content: flex-start;
    overflow-x: auto;
    padding-bottom: var(--spacing-sm);
    -webkit-overflow-scrolling: touch;
  }
  
  .filter-btn {
    white-space: nowrap;
  }
}

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

.post-card {
  animation: fadeIn 0.5s ease forwards;
}

.post-card:nth-child(1) { animation-delay: 0.1s; }
.post-card:nth-child(2) { animation-delay: 0.2s; }
.post-card:nth-child(3) { animation-delay: 0.3s; }
.post-card:nth-child(4) { animation-delay: 0.4s; }
.post-card:nth-child(5) { animation-delay: 0.5s; }
.post-card:nth-child(6) { animation-delay: 0.6s; }

/* Print Styles */
@media print {
  .site-header,
  .site-footer,
  .filter-bar,
  .pagination {
    display: none;
  }
  
  .post-card {
    break-inside: avoid;
    page-break-inside: avoid;
  }
}