/**
 * home_v2.css — homepage.php 专用样式表 (Plan C, 2026-08-31)
 *
 * 架构：
 *   1. @import home.css 主体（保持 homepage 视觉与 home_legacy.php 一致）
 *   2. CSS 变量（navbar.php / tool.php / about.php 等 partial 共用）
 *      ← 从 style.css L3-50 提取，替换 CSS var() 为静态值
 *   3. Navbar 样式（scoped .homepage）
 *      ← 从 style.css L116-330 navbar partial 提取
 *      ← 不引入 style.css 主体（避免 .logo / .features / .hero 等冲突）
 *   4. 覆盖层：缺失类 + 冲突修正
 *      ← .footer-col（home.css 无，style.css 有）
 *      ← .preview（home.css / style.css 均无）
 *
 * 更新 homepage.php 后删除 home.css 的 <link>，替换为：
 *   <link rel="stylesheet" href=".../home_v2.css?v=20260831">
 *
 * home_legacy.php / tool.php / about.php / contact.php / privacy.php
 *   → 继续用各自的 <link>，不受本文件影响。
 *
 * CSS 规范：所有 @import 必须放在最前。
 */

/* ============================================================
   1. home.css 主体（import）
   ============================================================ */
@import url('home.css?v=20260830');

/* ============================================================
   2. CSS 变量（navbar partial / tool.php / footer / btn 等共用）
   ============================================================ */
:root {
  /* 品牌色 */
  --primary: #4F46E5;
  --primary-hover: #4338CA;
  --primary-light: #EEF2FF;

  /* 灰度 */
  --gray-50:  #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;

  /* 文本色 */
  --text-primary:   #1F2937;
  --text-secondary: #6B7280;
  --text-muted:     #9CA3AF;

  /* 背景色 */
  --bg-primary:   #FFFFFF;
  --bg-secondary: #F9FAFB;
  --bg-tertiary: #F3F4F6;

  /* 间距 */
  --spacing-xs:  4px;
  --spacing-sm:  8px;
  --spacing-md:  16px;
  --spacing-lg:  24px;
  --spacing-xl:  32px;
  --spacing-2xl: 48px;

  /* 圆角 */
  --radius-sm:   0.25rem;
  --radius-md:   0.375rem;
  --radius-lg:   0.5rem;
  --radius-xl:   0.75rem;
  --radius-2xl:  1rem;
  --radius-full: 9999px;

  /* 阴影 */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

  /* 过渡 */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;

  /* 字体 */
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', Consolas, 'Liberation Mono', monospace;

  /* 行高 */
  --leading-tight:   1.25;
  --leading-normal:  1.5;
  --leading-relaxed: 1.625;
}

/* ============================================================
   3. Navbar 样式（scoped .homepage — 防止与 home.css .logo 等冲突）
   ============================================================ */
.homepage .navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #FFFFFF;
  border-bottom: 1px solid #E5E7EB;
  box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.homepage .navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* logo: navbar 版本（home.css 有 .logo { bg:transparent;...}
   navbar 需要 display:flex 而非 background, 故 scoped 优先 */
.homepage .logo {
  display: flex;
  align-items: center;
  padding: 4px 0;
}

.homepage .logo img {
  height: 28px;
  width: auto;
}

.homepage .logo:hover img {
  opacity: 0.85;
}

/* nav-links / nav-link */
.homepage .nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.homepage .nav-link {
  font-weight: 500;
  color: #6B7280;
  padding: 8px 0;
  position: relative;
  font-family: var(--font-sans);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.homepage .nav-link:hover,
.homepage .nav-link.active {
  color: #4F46E5;
}

.homepage .nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: #4F46E5;
  transition: width var(--transition-fast);
}

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

/* nav-dropdown */
.homepage .nav-dropdown {
  position: relative;
  display: flex;
  align-items: center;
}

.homepage .nav-dropdown::before {
  content: '';
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  height: 4px;
}

.homepage .nav-dropdown-toggle {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: transparent;
  border: none;
  cursor: pointer;
  font: inherit;
  color: #6B7280;
  font-weight: 500;
  padding: 8px 0;
  position: relative;
  text-decoration: none;
}

.homepage .nav-dropdown-toggle::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: #4F46E5;
  transition: width var(--transition-fast);
}

.homepage .nav-dropdown-toggle:hover::after,
.homepage .nav-dropdown.open .nav-dropdown-toggle::after {
  width: 100%;
}

.homepage .nav-dropdown-toggle:hover,
.homepage .nav-dropdown.open .nav-dropdown-toggle {
  color: #4F46E5;
}

.homepage .nav-dropdown-icon,
.homepage .nav-chevron {
  width: 14px;
  height: 14px;
  transition: transform var(--transition-fast);
}

.homepage .nav-dropdown.open .nav-dropdown-icon,
.homepage .nav-dropdown.open .nav-chevron {
  transform: rotate(180deg);
}

/* nav-dropdown-menu */
.homepage .nav-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 220px;
  margin-top: 4px;
  padding: 8px;
  background: #FFFFFF;
  border: 1px solid #E5E7EB;
  border-radius: 0.5rem;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  z-index: 110;
  display: none;
  max-height: 70vh;
  overflow-y: auto;
}

.homepage .nav-dropdown.open .nav-dropdown-menu,
.homepage .nav-dropdown:hover > .nav-dropdown-menu,
.homepage .nav-dropdown:focus-within > .nav-dropdown-menu {
  display: block;
}

.homepage .nav-dropdown-item {
  display: block;
  padding: 8px 16px;
  border-radius: 0.375rem;
  color: #1F2937;
  font-size: 0.9375rem;
  line-height: 1.4;
  transition: background var(--transition-fast), color var(--transition-fast);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  text-decoration: none;
}

.homepage .nav-dropdown-item:hover,
.homepage .nav-dropdown-item.active {
  background: #F3F4F6;
  color: #4F46E5;
}

.homepage .nav-dropdown-empty {
  display: block;
  padding: 8px 16px;
  color: #9CA3AF;
  font-size: 0.875rem;
  font-style: italic;
}

.homepage .nav-link--secondary {
  color: #9CA3AF;
  font-size: 0.9375rem;
  font-weight: 400;
}

/* navbar-toggle (mobile hamburger — 暂未启用, 无 JS handler) */
.homepage .navbar-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  padding: 6px;
  background: transparent;
  border: 1px solid #E5E7EB;
  border-radius: 0.375rem;
  cursor: pointer;
  margin-left: 8px;
}

.homepage .navbar-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background: #6B7280;
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* lang-switcher (navbar.php 新版: .lang-btn / .lang-dropdown / .lang-current / .lang-chevron)
   home.css 只有旧版的 .lang-switcher-icon / .lang-switcher-label, 不能复用
   完整提取自 style.css L333-400, scoped .homepage 防止与 home.css 冲突 */
.homepage .lang-switcher {
  position: relative;
  display: inline-flex;
  align-items: center;
}

.homepage .lang-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: 6px;
  color: #6B7280;
  transition: all 150ms ease;
  cursor: pointer;
  background: transparent;
  border: none;
  font: inherit;
}

.homepage .lang-chevron {
  transition: transform 150ms ease;
  color: #9CA3AF;
}

.homepage .lang-switcher.open .lang-chevron {
  transform: rotate(180deg);
}

.homepage .lang-btn:hover {
  background: #F3F4F6;
  color: #1F2937;
}

.homepage .lang-dropdown {
  position: absolute;
  top: 100%;
  right: 0;
  min-width: 160px;
  margin-top: 8px;
  padding: 8px;
  background: #FFFFFF;
  border: 1px solid #E5E7EB;
  border-radius: 8px;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 150ms ease;
  z-index: 110;
  max-height: 70vh;
  overflow-y: auto;
}

.homepage .lang-dropdown.show,
.homepage .lang-switcher:hover .lang-dropdown,
.homepage .lang-switcher:focus-within .lang-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.homepage .lang-dropdown a {
  display: block;
  padding: 8px 16px;
  border-radius: 6px;
  color: #6B7280;
  transition: all 150ms ease;
  text-decoration: none;
  font-size: 0.9375rem;
  white-space: nowrap;
}

.homepage .lang-dropdown a:hover,
.homepage .lang-dropdown a.active {
  background: #EEF2FF;
  color: #4F46E5;
}

/* ============================================================
   4. 覆盖层：缺失类 + 冲突修正
   ============================================================ */

/* .footer-col: footer grid 列 (home.css 有 .footer-col-title 但无 .footer-col) */
.footer-col {
  display: flex;
  flex-direction: column;
}

/* .preview: 上传区预览图容器 (home.js 动态填充) */
.preview {
  display: none;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.preview.has-files {
  display: flex;
}

/* ============================================================
   5. 移动端降级 (无 JS, 桌面布局强制 wrap)
   ============================================================ */
@media (max-width: 768px) {
  .homepage .navbar-toggle {
    display: none; /* 强制隐藏, 没有 JS handler */
  }

  .homepage .nav-links {
    flex-wrap: wrap;
    gap: 16px;
  }
}