/*
Theme Name: 懂AI
Theme URI: https://dong.xs91.com
Author: 萧盛
Author URI: https://xiaosheng.net
Description: 懂AI——面向普通人的AI资讯与教程社区主题。白底科技风，简洁大方，移动端适配。
Version: 1.0.0
Requires at least: 6.0
Tested up to: 6.9
Requires PHP: 7.4
License: GNU General Public License v2 or later
License URI: https://www.gnu.org/licenses/gpl-2.0.html
Text Domain: dongai
Tags: blog, technology, clean, responsive, custom-menu, featured-images, post-thumbnails
*/

/* ========================================
   CSS 变量
======================================== */
:root {
  --color-primary: #2563EB;
  --color-primary-dark: #1D4ED8;
  --color-accent: #06B6D4;
  --color-dark: #0A1628;
  --color-text: #1E293B;
  --color-text-secondary: #64748B;
  --color-border: #E2E8F0;
  --color-bg: #FFFFFF;
  --color-bg-soft: #F8FAFC;
  --color-tag-bg: #EFF6FF;
  --color-tag-text: #2563EB;
  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --radius: 10px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.10);
  --shadow-hover: 0 8px 28px rgba(37,99,235,0.13);
  --transition: all 0.22s ease;
}

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

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

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--color-primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--color-primary-dark); }

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

/* ========================================
   布局容器
======================================== */
.site-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========================================
   顶部导航
======================================== */
.site-header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.site-branding {
  display: flex;
  align-items: center;
  gap: 10px;
}

.site-logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: #fff;
  font-weight: 700;
  flex-shrink: 0;
}

.site-title {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--color-dark);
  letter-spacing: -0.01em;
}

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

.site-tagline {
  font-size: 0.72rem;
  color: var(--color-text-secondary);
  margin-top: 1px;
}

/* 主导航 */
.main-nav ul {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 4px;
}

.main-nav ul li a {
  display: block;
  padding: 6px 14px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text);
  border-radius: 6px;
  transition: var(--transition);
}

.main-nav ul li a:hover,
.main-nav ul li.current-menu-item a,
.main-nav ul li.current-menu-ancestor a {
  background: var(--color-tag-bg);
  color: var(--color-primary);
}

/* 汉堡菜单（移动端） */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  color: var(--color-text);
}

.menu-toggle svg { display: block; }

/* ========================================
   Header 用户登录/注册区域
======================================== */
.header-user-area {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  margin-left: 12px;
}

/* 未登录：登录/注册按钮 */
.header-auth-btns {
  display: flex;
  align-items: center;
  gap: 8px;
}

.header-login-btn {
  font-size: 14px;
  color: var(--color-text);
  text-decoration: none;
  padding: 5px 12px;
  border-radius: 6px;
  transition: color 0.2s;
}
.header-login-btn:hover { color: var(--color-primary); }

.header-register-btn {
  font-size: 14px;
  color: #fff;
  text-decoration: none !important;
  background: var(--color-primary);
  padding: 6px 14px;
  border-radius: 6px;
  font-weight: 600;
  transition: background 0.2s;
  white-space: nowrap;
}
.header-register-btn:hover { background: var(--color-primary-dark); color: #fff; }

/* 已登录：头像下拉 */
.header-user-dropdown { position: relative; }

.header-user-btn {
  display: flex;
  align-items: center;
  gap: 7px;
  background: none;
  border: 1.5px solid var(--color-border);
  border-radius: 24px;
  padding: 4px 12px 4px 4px;
  cursor: pointer;
  font-size: 14px;
  color: var(--color-text);
  transition: border-color 0.2s;
}
.header-user-btn:hover { border-color: var(--color-primary); }

.header-avatar {
  width: 28px !important;
  height: 28px !important;
  border-radius: 50% !important;
}

.header-username {
  max-width: 80px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.header-vip-tag {
  background: linear-gradient(135deg, #f59e0b, #d97706);
  color: #fff;
  font-size: 10px;
  font-weight: 700;
  padding: 1px 6px;
  border-radius: 10px;
  letter-spacing: 0.5px;
}

.header-dropdown-menu {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 160px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 10px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.10);
  z-index: 9999;
  overflow: hidden;
  padding: 4px 0;
}
.header-dropdown-menu.is-open { display: block; }

.header-dropdown-menu a {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  font-size: 14px;
  color: var(--color-text);
  text-decoration: none;
  transition: background 0.15s;
}
.header-dropdown-menu a:hover { background: var(--color-bg-soft); color: var(--color-primary); }

.dropdown-divider {
  height: 1px;
  background: var(--color-border);
  margin: 4px 0;
}

/* ========================================
   Hero Banner（首页）
======================================== */
.hero-banner {
  background: linear-gradient(135deg, var(--color-dark) 0%, #0F2552 60%, #0E3A6B 100%);
  padding: 72px 0 64px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero-banner::before {
  content: '';
  position: absolute;
  top: -60px; right: -60px;
  width: 320px; height: 320px;
  background: radial-gradient(circle, rgba(6,182,212,0.18) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-banner::after {
  content: '';
  position: absolute;
  bottom: -80px; left: -40px;
  width: 260px; height: 260px;
  background: radial-gradient(circle, rgba(37,99,235,0.2) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-content { position: relative; z-index: 1; }

.hero-badge {
  display: inline-block;
  background: rgba(6,182,212,0.15);
  border: 1px solid rgba(6,182,212,0.4);
  color: var(--color-accent);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 100px;
  margin-bottom: 20px;
  letter-spacing: 0.05em;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900;
  color: #fff;
  line-height: 1.2;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-title em {
  font-style: normal;
  background: linear-gradient(90deg, var(--color-accent), #818CF8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.7);
  max-width: 520px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--color-primary);
  color: #fff;
  padding: 11px 26px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: var(--transition);
  box-shadow: 0 4px 14px rgba(37,99,235,0.4);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(37,99,235,0.5);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1.5px solid rgba(255,255,255,0.35);
  color: rgba(255,255,255,0.85);
  padding: 10px 24px;
  border-radius: 8px;
  font-weight: 500;
  font-size: 0.95rem;
  transition: var(--transition);
}

.btn-outline:hover {
  border-color: rgba(255,255,255,0.7);
  color: #fff;
  background: rgba(255,255,255,0.08);
}

/* ========================================
   主内容区域
======================================== */
.site-main {
  padding: 56px 0 72px;
}

.content-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 40px;
  align-items: start;
}

/* ========================================
   分区标题
======================================== */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.section-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-dark);
  display: flex;
  align-items: center;
  gap: 8px;
}

.section-title::before {
  content: '';
  display: block;
  width: 4px;
  height: 20px;
  background: linear-gradient(180deg, var(--color-primary), var(--color-accent));
  border-radius: 2px;
}

.section-more {
  font-size: 0.85rem;
  color: var(--color-primary);
  font-weight: 500;
}

.section-more:hover { color: var(--color-primary-dark); }

/* ========================================
   文章卡片
======================================== */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.post-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}

.post-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
  border-color: transparent;
}

.post-card-thumb {
  width: 100%;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--color-bg-soft);
}

.post-card-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.35s ease;
}

.post-card:hover .post-card-thumb img {
  transform: scale(1.04);
}

.post-card-no-thumb {
  width: 100%;
  aspect-ratio: 16/9;
  background: linear-gradient(135deg, var(--color-bg-soft), #EFF6FF);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  color: var(--color-primary);
  opacity: 0.5;
}

.post-card-body {
  padding: 18px 20px 20px;
}

.post-card-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.post-cat-tag {
  display: inline-block;
  background: var(--color-tag-bg);
  color: var(--color-tag-text);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 2px 10px;
  border-radius: 100px;
  letter-spacing: 0.03em;
}

.post-date {
  font-size: 0.78rem;
  color: var(--color-text-secondary);
}

.post-card-title {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.5;
  margin-bottom: 8px;
}

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

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

.post-card-excerpt {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.65;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* 首篇大卡片 */
.post-card-featured {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.post-card-featured .post-card-thumb,
.post-card-featured .post-card-no-thumb {
  aspect-ratio: auto;
  height: 100%;
  min-height: 220px;
}

.post-card-featured .post-card-title {
  font-size: 1.2rem;
}

.post-card-featured .post-card-excerpt {
  -webkit-line-clamp: 3;
}

/* ========================================
   分页
======================================== */
.pagination {
  display: flex;
  justify-content: center;
  gap: 6px;
  margin-top: 40px;
}

.pagination .page-numbers {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text);
  transition: var(--transition);
}

.pagination .page-numbers:hover,
.pagination .page-numbers.current {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

/* ========================================
   侧边栏
======================================== */
.sidebar {
  position: sticky;
  top: 80px;
}

.widget {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 22px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.widget-title {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--color-dark);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--color-primary);
  display: flex;
  align-items: center;
  gap: 6px;
}

/* 热门文章 */
.popular-posts-list {
  list-style: none;
}

.popular-posts-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--color-border);
  display: flex;
  gap: 10px;
  align-items: flex-start;
}

.popular-posts-list li:last-child { border-bottom: none; padding-bottom: 0; }

.popular-num {
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--color-text-secondary);
  background: var(--color-bg-soft);
  min-width: 22px;
  height: 22px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  flex-shrink: 0;
  margin-top: 2px;
}

.popular-posts-list li:nth-child(1) .popular-num { background: #FEF3C7; color: #D97706; }
.popular-posts-list li:nth-child(2) .popular-num { background: #F1F5F9; color: #475569; }
.popular-posts-list li:nth-child(3) .popular-num { background: #FEF9C3; color: #CA8A04; }

.popular-title {
  font-size: 0.875rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--color-text);
}

.popular-title a { color: inherit; }
.popular-title a:hover { color: var(--color-primary); }

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

.tag-cloud a {
  display: inline-block;
  background: var(--color-bg-soft);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  padding: 4px 12px;
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 500;
  transition: var(--transition);
}

.tag-cloud a:hover {
  background: var(--color-tag-bg);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* 关于站点 widget */
.about-widget-avatar {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  margin: 0 auto 12px;
}

.about-widget-name {
  text-align: center;
  font-weight: 700;
  font-size: 1rem;
  color: var(--color-dark);
  margin-bottom: 6px;
}

.about-widget-desc {
  font-size: 0.83rem;
  color: var(--color-text-secondary);
  text-align: center;
  line-height: 1.65;
}

/* ========================================
   单篇文章
======================================== */
.single-post-header {
  background: var(--color-bg-soft);
  padding: 48px 0 40px;
  border-bottom: 1px solid var(--color-border);
}

.post-header-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.post-header-title {
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  font-weight: 900;
  color: var(--color-dark);
  line-height: 1.35;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

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

.post-header-info span {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* 文章内容 */
.entry-content {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 0;
  font-size: 1.03rem;
  line-height: 1.85;
  color: var(--color-text);
}

.entry-content h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-dark);
  margin: 2.5em 0 0.8em;
  padding-left: 14px;
  border-left: 3px solid var(--color-primary);
}

.entry-content h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-dark);
  margin: 2em 0 0.7em;
}

.entry-content p { margin-bottom: 1.4em; }

.entry-content img {
  border-radius: 8px;
  margin: 1.5em auto;
  box-shadow: var(--shadow-md);
}

.entry-content blockquote {
  border-left: 3px solid var(--color-accent);
  background: var(--color-bg-soft);
  padding: 16px 20px;
  border-radius: 0 8px 8px 0;
  margin: 1.5em 0;
  color: var(--color-text-secondary);
  font-style: italic;
}

.entry-content code {
  background: #F1F5F9;
  color: #0F172A;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
  font-family: "Fira Code", "Cascadia Code", Consolas, monospace;
}

.entry-content pre {
  background: var(--color-dark);
  color: #E2E8F0;
  padding: 20px 24px;
  border-radius: 8px;
  overflow-x: auto;
  margin: 1.5em 0;
  font-size: 0.9rem;
}

.entry-content pre code {
  background: none;
  color: inherit;
  padding: 0;
}

.entry-content ul, .entry-content ol {
  padding-left: 1.5em;
  margin-bottom: 1.4em;
}

.entry-content li { margin-bottom: 0.4em; }

.entry-content a {
  color: var(--color-primary);
  border-bottom: 1px solid rgba(37,99,235,0.3);
}

.entry-content a:hover {
  border-bottom-color: var(--color-primary);
}

/* ========================================
   页脚
======================================== */
.site-footer {
  background: var(--color-dark);
  color: rgba(255,255,255,0.55);
  padding: 48px 0 28px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 36px;
}

.footer-brand .site-title {
  color: #fff;
  font-size: 1.3rem;
  margin-bottom: 10px;
  display: block;
}

.footer-brand .site-title span { color: var(--color-accent); }

.footer-desc {
  font-size: 0.85rem;
  line-height: 1.7;
  max-width: 260px;
}

.footer-col-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 14px;
}

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

.footer-links a {
  color: rgba(255,255,255,0.5);
  font-size: 0.85rem;
  transition: var(--transition);
}

.footer-links a:hover { color: rgba(255,255,255,0.9); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  flex-wrap: wrap;
  gap: 8px;
}

.footer-bottom a { color: rgba(255,255,255,0.5); }
.footer-bottom a:hover { color: #fff; }

/* ========================================
   移动端响应式
======================================== */
@media (max-width: 900px) {
  .content-layout {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
  }

  .footer-inner {
    grid-template-columns: 1fr 1fr;
  }

  .posts-grid {
    grid-template-columns: 1fr;
  }

  .post-card-featured {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .main-nav { display: none; }
  .main-nav.is-open { display: block; }

  .menu-toggle { display: block; }

  .main-nav ul {
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: 12px 24px 16px;
    box-shadow: var(--shadow-md);
    gap: 2px;
  }

  .main-nav ul li a {
    padding: 10px 14px;
  }

  .hero-banner { padding: 48px 0 40px; }

  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn-primary,
  .hero-actions .btn-outline { justify-content: center; }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .footer-bottom { flex-direction: column; text-align: center; }

  .section-header { flex-direction: column; align-items: flex-start; gap: 6px; }
}